Meteorological Society of New Zealand (Inc.)

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 1

ISSN 0111 - 1736

Meteorological Society Of New Zealand (Inc.)

NEWSLETTER 153 Winter 2018

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 2 Meteorological Society Of New Zealand (Inc.) NEWSLETTER 153 Winter 2018 PO Box 6523, Marion Square, Wellington 6141, New Zealand Please forward contributions to Bob McDavitt, [email protected]

CONTENTS Page Foreword from our President 3 Conference 2018 4 Student Report POLAR 2018 5 Around the Regions in Autumn 6 Autumn: NIWA review 7 Notable events 8 - 14 Christchurch, Ben Tichborne 15 Pick of the clips 16 - 52

Your Committee 2018 President Sylvia Nichol Immediate Past President Daniel Kingston Secretary Katrina Richards Treasurer Gregor Macara Circulation Manager Lisa Murray Auckland VP Petra Pearce Hamilton VP Tim Gunn Wellington VP James Renwick Christchurch VP Jiawei Zhang Dunedin VP Daniel Kingston Journal Editor Nava Fedaeff with Jim Renwick Newsletter Editor Bob McDavitt Website Liaison Stefanie Kremser General Committee Mike Revell, Michael Martens Hydrological Society liason Charles Pearson Co - opted by committee Ciaran Doolin

Views and endorsements expressed in this newsletter are those of the contributors and advertisers, and not necessarily those of the Meteorological Society of New Zealand. The mention of specific companies or products does not imply that they are endorsed or recommended by the Society.

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 3 Notes from the President ’ s desk

Dear Members

It gives me great pleasure to let you know that our new website has been up and running for a few weeks now.

One of the big changes is that the back - end of the new website now holds the mem- bership database for members who have an email address, and so from now on the website should automacally send email reminders to tell members that their annual subscripon is due.

Members who haven ’ t supplied us with an email address will connue to receive an invoice for their annual subscripon through the post. This process should dramacal- ly reduce the workload for our Treasurer and Circulaon Manager in tracking subscripon payments. Many thanks are due to our Website Liaison, Stefanie Kremser, for all the work that has gone into this project.

I have been very encouraged by the recent news that the chief execuves of 60 companies have formed the Climate Leaders Coalion and commied their companies to help New Zealand transion to a low carbon emissions economy. This, along with the recent public consultaon process on the Zero Carbon Bill, shows that we are moving in the right direcon on this important issue.

Sylvia Nichol, President NZ Met Society July 2018

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 4

2018 Conference is in Christchurch from 4 to 7 December with NZ Hydro Soc See hp://nzhsnzms2018.co.nz/

Who ’ s on the Climate Leaders Coalion? See hps://www.climateleaderscoalion.org.nz/

Student ’ s Grant Conference report

POLAR2018 – a joint conference of the SCAR (Scienﬁc Commiee on Antarcc Research and the IASC (Internaonal Arcc Science Commiee) had the appropriate tagline of “ where the poles come together ”. The meeng was held in Davos, Switzerland from the 19 - 23 June 2018. Chris Cameron aended with the support of a Student Travel Grant from the Meteorological Society of New Zealand, and reports back here on his experience.

Though I had heard plenty about Davos, as both a hub for snow and ice research and as a winter ski resort, I had not begun to imagine how stunning the scenery would be. An idyllic seng for the conference to be held.

My poster presentaon was on day two, and was one of many hundreds of posters on display – with similarly large numbers of viewers. Aer several good discussions, I spoke at some length with the two poster judges about my work. My poster covered the latest findings on my PhD research into the characteriscs of the Antarcc circumpolar strato- spheric vortex - comparing how well it is represented as a mixing barrier in reanalysis compared with the UK MetOffice Unified Model (UM) and how representaon of the vortex in the latest dynamical core of the UM differs from the previous core.

Apart from other presentaons on atmospheric science, one of the great beneﬁts of PO- LAR2018 was the ability to aend talks on a wide range of polar related topics. These were fascinang in terms of the range of acvity taking place. Sessions I aended included: Introducing the new ‘ Iridium Certus ’ satellites for global telecommunicaons The next phase of work for the BBC Frozen Planet documentary series Polar related art, including ﬁlm and visual art Polar change and the future of society

I am very grateful for support from the Meteorological Society for assisng me to aend POLAR2018. Thanks, MetSoc!

Chris Cameron

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 6

Parcipants aend a plenary session during POLAR2018

AROUND the REGIONS IN AUTUMN

Just one seminar was distributed to regional Met Soc members during autumn, but it was a good one: Wahine Day at Wellington Museum In commemoraon of the 50 th Anniversary of the Wahine Disaster, Wellington Museum hosted a number of special events that will happen during the day – in rememberance of the people who lost their lives, as well as the survivors and ﬁrst responders who were there ﬁy years ago. A special Wahine exhibion was displayed in the Museum as well as talks, and there was acknowledg- ment of th e Wahine with bell ringing every half - hour. Including, at 6pm Erick Brenstrum, Expert Meteorologist from the METSERVICE talked about the weather forecast for the 10th April 1968.

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AUTUMN A warm start to autumn, then cooler and unseled at mes. Temperature Nearly all of the North Island observed above average (0.51 to 1.20°C of average) temperatures during autumn, along with isolated pockets of near average ( - 0.50 to 0.50°C of average) and well above average (>1.20°C of average) temperatures. In the South Island, most locaons recorded near average ( - 0.50 to 0.50°C of average) temperatures during autumn, with a handful of staons observing above average (0.51 to 1.20°C of average) temperatures. Rainfall Autumn rainfall in the North Island was generally near normal (80 - 119% of normal) or above normal (120 - 149% of normal), with a handful of locaons also recording well above normal (>149% of normal) rainfall. In the South Island, above normal (120 - 149% of normal) or well above normal (>149% of normal) rainfall was observed in most locaons, with a few spots also recording near normal (80 - 119% of normal) rainfall. Soil moisture As of 1 June, soil moisture was near normal in most of the North Island, along with the western and southern South Island. However, soils were weer or even much weer than normal in small porons of the lower North Island and nearly all of the eastern South Island. Overview Autumn 2018 began on a warm note, as March was characterised by significantly higher pressure than normal to the east of New Zealand. This pressure paern, in concert with the decaying La Niña in the tropical Pacific, caused more northeasterly winds than usual over the country. Warm, humid air mass- es, combined with the remnants of the marine heatwave in the Tasman Sea, influenced higher than usual temperatures over New Zealand as well as some heavy rainfall events. However, the pressure paern for April resulted in more southwesterly winds than normal for much of the country. Several low pressure systems and cold fronts passed over New Zealand, bringing adverse weather to many locaons. Storms occurring on the 10th - 11th and 28th - 29th days of the month were parcularly damaging with the former bringing destrucve winds to Auckland, while the laer brought heavy rain to parts of the country, resulng in flooding and the declaraon of a state of emergency in Rotorua. In May, mean sea level air pressures were much lower than normal over and to the south of New Zea- land. The first half of the month was relavely warm and dry throughout the country. However, during the second half of May, a blocking ancyclone became established over the southeast of Australia, which delivered a prolonged period of disturbed westerly and southwesterly winds over the country. A ridge of high pressure covered the lower South Island during the final days of May, bringing heavy frosts and record cold temperatures to parts of Central Otago, Southland and the Mackenzie Basin. Further highlights The highest temperature was 31.8°C, observed at Kawerau on 5 March. The lowest temperature was - 8.8°C, observed at Mt Cook Airport on 31 May. The highest 1 - day rainfall was 205 mm, recorded at Secretary Island on 19 March. The highest wind gust was 187 km/hr, observed at Akio on 21 May. Of the six main centres in autumn 2018, Auckland was the warmest, Dunedin was the coolest and least sunny, Auckland and Wellington were the equal - weest, Christchurch was the driest, and Tauranga was the sunniest. Contact For further informaon, please contact: Mr Chris Brandolino, Principal Scienst – Forecasng, NIWA Naonal Climate Centre Tel. 09 375 6335, Mobile 027 866 0014 Mr Seth Carrier, Meteorologist/Forecaster, NIWA Naonal Climate Centre Tel. 09 375 4508

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 8

NOTABLE WEATHER IN NZ – AUTUMN 2018

This autumn was very varied with regards to weather. There were several stormy spells, with a few of them causing severe damage, due to high winds and heavy rain. Temperatures were very variable, with some warm periods, but also some early wintry outbreaks.

MARCH 1 st – Unusually warm in northwest of South Island in a northeasterly flow, eg 27C maximum at Arapito. (near Karamea) 3rd – Warm day on South Island West Coast, eg 28C maximum in Westport. 4 th – Heavy fog blankets Otago Harbour, disrupng operaons at Port Chalmers. 5 th/ 6 th – Very warm in many parts of North Island, especially in the north. New March records of 28C broken in Whianga (6 th ) and Rotorua. (5 th ) Other highs include 29C in Hamilton and Te Kui (both on 5 th ), 28C in Paeroa (5 th ), 27C in Mangere, Auckland (6 th ), and 26C at Motu. (6 th ) Overnight minimums are also very high in many areas, eg 19C at Wellington Airport on 6 th . Thick fog disrupts operaons at Auck- land Airport in morning. 7 th /8 th – Heavy rain in parts of North Island, with locally severe flooding in parts of Hawkes Bay. (see details below) 12 th – Ex - tropical cyclone brings heavy rain to eastern Northland, Coromandel Peninsula, and East Cape. (as much as 100mm recorded in laer two areas) 13 th – A few aernoon thunderstorms reported in North Canterbury. 19 th – Heavy rain in Fiordland. Secretary Island records 205mm, its highest recorded March daily total. Northwesterly gales in exposed parts of lower South Island, eg 109 km/hr gust recorded at Lauder. 21 st – Heavy downpour causes flooding in New Plymouth. 22 nd – Unusually cold in lower South Island, under cloud, rain, and a southerly flow. Snow down to about 700m in Central Otago, with 30cm recorded at Cardrona Ski Resort. Record March low maximums recorded in Wanaka (6C) and Oamaru (9C), while highs in high single figures recorded at many other Otago and Southland staons. Further north, heavy rain affects many central areas, with flooding reported about Nelson and the Kapi Coast. (some homes flooded in laer area) 130mm recorded in Straord, and 105mm in Nelson. 23 rd – Heavy downpour in the far north causes a washout on SH1 between Kaitaia and Cape Reinga. 24 th – Thunderstorms with a few heavy downpours reported in West Auckland. 27 th – Northwesterly gales in some inland eastern parts of South Island. Campervan blown over by the winds near Mt Cook Village, while scenic flights are cancelled in that area. 31 st – Thunderstorm reported near Oamaru, during a southerly change in the aernoon.

APRIL 2 nd – Unusually warm 23C maximum in Lumsden, in a northwesterly flow. 3 rd – Unusually warm 25C maximum in Takaka. 4 th – Warm day in east of South Island, eg 26C maximum in Oamaru. 5 th - Warm in north of North Island (eg 24C maximum in Rotorua and 27C in Whianga), under sunshine and light winds. 6 th – Warm northwesterly flow results in summery maximums in east of South Island, eg 28C in Akaroa. 9 th - 13 th – Stormy period, including damaging winds in Auckland and an unseasonably early wintry blast. (see details below) 14 th – Unseasonably heavy frosts in Central Otago and Southland, eg - 4C minimums in Clyde and Lumsden. 15 th – Thunderstorms on South Island West Coast. 19 th /20th – Westerly gales in some exposed eastern areas, eg 141 km/hr gust at Castlepoint (19 th ), and 82 km/hr in Dannevirke. (20 th ) 20 th /20 th – Cold and showery in far south in a strong west to southwest flow, with snow above about

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700m on high country. Late aernoon/evening southerly change brings thunder and hail in parts of Canterbury, including Christchurch. 21 st – Snow on lower South Island high country (including a dusng at Mt Cook Village) in morning, in a cold but easing southwesterly ﬂow. 27 th - 30 th – Heavy rain in many areas, with severe ﬂooding around Rotorua. (see details below)

MAY 1 st – Unseasonably warm in northern areas, eg 23C maximums in Hamilton (new May record) and Tau- ranga, 22C in Te Puke and Whakatane, 21C in Taupo, and 20C in Rotorua. 8 th – Northwesterly gales in the far south, eg 89 km/hr gust recorded at Manapouri (new May record), 153 km/hr at Puysegur Point, 107 km/hr in Gore, and 85 km/hr in Queenstown. 9 th – Unusually warm in north of South Island, eg 23C maximum in Motueka, and 19C on Brothers Is- land. 11 th – Some heavy rain in northern and central North Island. 152mm recorded at North Egmont. 12 th – Freezing fog in parts of Otago and Southland. Only 5C maximum in Alexandra. 13 th – Only 4C maximum in Alexandra, as freezing fog and cloud connues. By contrast, warm north to northwest flow pushes maximums up to 23C at Whenuapai, Auckland, and 21C in Whangaparoa. 14 th – Warm, humid north to northwest flow connues in northern areas, with a 23C maximum at Western Springs, Auckland, and 22C in Hamilton. Heavy rain in eastern Bay of Plenty, eg 117mm in Whakatane. Thunderstorms in Taranaki, with lightning strikes causing power - cuts to more than 2000 properes. 15 th – Strong wind gusts cause some damage in and around Tauranga. 16 th – Warm in north and east of North Island, eg 24C maximum in Wairoa, and 23C in Whianga. 17 th – Disturbance in southwesterly flow brings period of thunderstorms to Auckland, with reports of large hail. 20 th – Northwesterly gales in some eastern areas of South Island. Winds cause disrupon to flights at Dunedin Airport and fan a fire near Taieri Mouth. Gusts reach 89 km/hr in Oamaru and 82 km/hr at Tara Hills. Thunderstorms about and west of the Southern Alps; lightning striking two aircra heading to Queenstown. (which had to be diverted) 21 st – Northwesterly gales cause some damage in Wairarapa. 187 km/hr gust recorded at Akio; 143 km/hr at Castlepoint. Thunderstorms affect Wellington/Kapi and Taranaki during the early hours, with some 700 lightning strikes recorded. Colder air affects southern South Island, with snow on the high country. SH 94 to Milford Sound closed by snowfall. 22 nd – Trough and fronts cross NZ, with strong northwesterly flow over NZ being replaced by strong, colder west to southwesterlies in the south. Heavy rain causes surface flooding in parts of Central Ota- go and inland Southland. About 9500 lightning strikes are recorded across New Zealand as thunderstorms affect many areas. Thunderstorm downpour with heavy hail also causes surface flooding in Wel- lington. 23 rd – Cold, unstable southwesterly flow spreads over NZ, with hail in several areas, especially the west and south, also Canterbury. (including parts of Christchurch in aernoon) Snow to low levels in inland Southland and parts of Otago. 24 th – Cold, disturbed southwesterly flow over NZ, with more thunder and hail in western and southern areas. Snow showers on high country areas of both island. SH94 to Milford Sound, SH6 Haast Pass, SH73 at Arthurs Pass, and SH1 Desert Road are closed by snow. 25 th – Unseled weather connues over NZ, as complex low forms, one centre to west of central NZ with west to northwest flow over North Island, while other centre lies to southeast of South Island with a cold south to southwest flow developing. Thunderstorms affect many parts of North Island, with about 575 lightning strikes reported in Taranaki, 400 in Waikato and about 100 in the Bay of Plenty. A few thunderstorms in early morning also over Banks Peninsula, and scaered hail in parts of Canter- bury later. Snow on southern high country. 27 th /28th – Strong, cold south to southwest change sweeping over NZ on 27 th , with cold southerly flow

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 10 persisng over country on 28 th . Snow showers on high country of both islands, with falls as low as 200m reported in North Canterbury. Desert Road closed overnight. Hail in some southern and eastern areas, eg Wellington during morning of 28 th . Dayme maximums were well below normal, especially on the 28 th , eg 2C in Waiouru, 6C at Waipara, 4C in Straord (new May record), 9C on Brothers Island, 11C at Whangaparoa. (another new May record, and 12C in Dargaville and Whenuapai. 29 th - 31 st – High gradually moves onto NZ during this period, though with a weakening cold southerly sll bringing showers to east of North Island. Elsewhere, frosts are widespread, and oen severe in inland areas. Overnight minimums include - 8C at Mt Cook Airport (31 st ), - 7C in Alexandra (30 th ), - 2C in Dunedin (31 st ), and 0C in Whangarei and Warkworth. (30 th ) Freezing fogs in Central Otago and the Mac- kenzie Country also supressed maximum temperatures. New record low maximums for May include - 2C at Lauder (31 st ), - 1C at Tara Hills, and 0C at Manapouri (30 th ) and Alexandra. (31 st )

MAJOR EVENTS 7 th - 9th March – Heavy rain in parts of North Island, with locally severe flooding in parts of Hawkes Bay A slow - moving frontal system to the south of a low resulted in very heavy rain in parts of the central and lower North Island, with severe flooding inland from Napier. A low which had developed in the North Tasman the day before, moved onto the west of the North Is- land late on the 7 th . Fronts on its eastern edge brought warm, moist air from the north onto the North Island. Meanwhile, cooler air from a southerly change over the South Island reached the lower North Island that night. The clash between the two systems resulted in rain becoming heavy in some central and lower North Island areas. Lower Retaruke (southern King Country) recorded 160mm, it ’ s weest March day on record, while other high totals included 110mm at Castlepoint, 85mm in Taumaranui, 67mm in Hawera, and 63mm in Turangi. The heavy rain persisted in these areas through the 8 th , as the low moved to the north of the Bay of Plenty, but frontal systems remained slow - moving to its south. Parcularly intense falls were recorded in the Esk Valley inland from Napier. Some 200 people had to be evacuated from the area, with more than 80 properes affected by the flooding. Elsewhere, SH43 was closed between Whangamomona and Taumaranui due to slips, and more than 100 tourists were trapped by slips and flooding on the upper Whanganui River for a me. High rainfall totals for the day included 92mm in Dannevirke and 57mm at Mahia. In the flood ravaged Esk Valley, there were reports of more than 300mm recorded in the two - day period. Overnight 8 th /9 th , the weather system weakened, with rain easing. A cool south to southeast flow spread over the North Island on the 9 th , with the weather sll damp in southern and eastern areas, but no more heavy falls.

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Mean sea - level analyses for 1pm NZDT 7th March to 1am NZDT 10th March in 12 - hour steps are shown here., courtesy of MetService

9 th - 13 th April – Stormy period, including damaging winds in Auckland and an unseasonably early wintry blast Low pressure systems crossed NZ during this period with stormy weather, including devastang winds in Auckland, and a very early wintry southerly with early snow to low levels on the high country of both islands. On the 9 th , a low deepened in the mid - Tasman Sea, with very cold southerlies to the south of it. Mild northerlies affected the North Island, but colder air gradually spread onto the South Island with snow levels lowering from the south later in the day. A strong, very cold southerly flow covered the South Island on the 10 th , spreading onto the lower North Island by later in the day. Snow fell to unusually low levels (about 200m) for so early in the year in the south and east of the island, and then reached the Central North Island high country by the end of the day. Record low April maximums included 1C in Hanmer, 4C in Culverden, 5C in Kaikoura, 7C in Rangio- ra, and 9C in Palmerstorn North. Gales on the West Coast felled trees and knocked over some vehicles, with SH6 closed for a me between Ross and Franz Josef and SH67 between Westport and Karamea also blocked. (this me by roofing iron blown off a building) Gusts reached 122k/hr at Westport Airport. As the low approached the North Island on the 10th, very strong and squally northwesterly winds lashed northern and western areas. Taranaki was hard hit by gales, with trees and properes damaged – some 12,000 properes losing power. More than 13,000 lightning strikes were recorded in the area. Two tornadoes were reported – one at Rahotu, Taranaki, and the other in Naonal Park township, both causing significant damage. About Cook Strait and Wellington, southerly gales and heavy rain developed, with some surface flooding about Central Wellington and Lower Hu. High gusts recorded included 139 km/hr at Brothers Island (new April record) and 143 km/hr on Mt Kaukau. All Inter Islander fer- ries were cancelled due to high seas in Cook Strait. (coincidentally, it was the 50 th anniversary of the Wahine disaster) However, the most significant wind damage occurred in the evening in Auckland. Overnight 10 th /11 th ,

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 12 gusts reached hurricane force, with widespread damage to trees, power - lines and buildings. Power was out to many areas, with 129 lines reported felled and about 120,000 properes losing power. Many homes and vehicles were severely damaged by fallen trees and numerous windows were smashed. Public transport (both on land and on the water) was badly disrupted and the airport was forced to close with the cancellaon of all flights. Not surprisingly, new record high gusts for April were recorded in the Auckland area, including 113 km/hr at Whenuapai, 95 km/hr at Western Springs, and 82 km/hr in Pukekohe. Unofficially, even higher gusts were recorded, including 146 km/hr at the Sky Tower. During the 11 th , the front and an associated low moved to the east of the North Island, with an unseasonably cold southerly flow over the country. Snow on the North Island high country briefly closed the Desert Road and fell as low as 500m. There were even exceponally early coangs of snow further north on Mt Tarawera and Pirongia. Dayme maximums not surprisingly were unseasonably low, with new April records broken in Waiouru (3C), Rotorua (9C), Whakatane (10C), and Warkworth. (14C) Thun- der and hail affected Wellington, with a lightning strike causing disrupon at the airport and heavy hail making some roads hazardous. Overnight 11 th /12, there was a clearance with frosts in many areas. Lows included 0C in Kaikoura, a new record for April. The clearance was short - lived however, with another trough moving in from the west on the 12th, with rain in western and southern areas, and more snow for the South Island high country. Strong southwesterlies followed the trough in southern areas, with gales in Central Otago, resulng in some trees felled and power cuts in Alexandra and Clyde.

Condions eased during the 13 th , as a weak ridge moved onto much of NZ.

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Mean sea - level analyses for midday NZST 9 th April to midday NZDT 13 th April in 12 - hour steps are Mean sea - level analyses for midday NZST 9 th April to midday NZDT 13 th April in 12 - hour steps are shown here, courtesy of MetService

27 th - 30 th April – Heavy rain in many areas, with severe flooding around Rotorua Another storm affected many areas during this period, with heavy rain, gales, and snow on the southern high country. The most significant weather recorded was a very heavy rainfall in the Rotorua Dis- trict with severe flooding resulng. A low deepened in the North Tasman during the 27 th , while a trough moved onto the South Island; colder southerlies developing in the south later. During the 28 th , the Tasman low moved only slowly eastward to lie west of Northland late in the day and remained there for most of the 29th. Fronts in a strong, humid northerly flow on its eastern side brought thunderstorms and heavy rain to the north of the North Island. Flooding affected many areas, with several roads closed on the Coromandel Peninsula and near Tauranga. Piha also experienced flooding when a stream burst its banks. This area was also lashed by gales, with yet more damage in Auckland. (trees felled and power cut) Gusts reached 128 km/hr in Mangere, Auckland and 102 km/hr

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 14 in Paeroa – both new April records. However, the Rotorua District was most severely affected. 167mm of rain fell on the 28 th /29 th , with 51mm falling in one hour from 10AM 29 th . (the city ’ s highest one - hour total on record) Surface flooding was widespread, with several vehicles submerged. A state of emergency was declared in Ngontotaha, where the Ngongotaha Stream burst its banks and flooded many properes. Some 200 people were trapped by the floodwaters at the Rotorua Agrodome. To the south of Rotorua (at Earthquake Flat), the rain caused a large fissure to open in an old fault - line. In the central and lower South Island, cold undercung air also brought heavy rain in some areas on the 28 th /29th. SH1 south of Timaru was affected by surface flooding, as was the Dunedin area where several roads were closed. Record high April rainfall totals were recorded on the 28 th at Timaru Airport (85mm) and 96mm at Orari Estate. Other high totals included 63mm in Dunedin (29 th ), 61mm in Ash- burton (28 th ), and 58mm in Waimate. (28 th ) Snow fell on the inland high country, as low as 600m in the Mackenzie Country. Three trampers were trapped by deep snow at about 1600m in Aoraki/Mt Cook Naonal Park and had to be rescued by rescue helicopter. The low weakened overnight on the 29 th /30 th but remained slow - moving over the North Island during the 30 th, while a weak ridge moved onto the South Island. Rain became lighter in most areas and cleared from the lower South Island. However, some more thunderstorms affected the western Bay of Plenty in the early morning, with a tree split in half in Te Puke and falling on a house.

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Mean sea - level analyses for midday NZST 27 th April to midday NZST 30 th April in 12 - hour steps are shown here., courtesy of MetService

MONTHLY WEATHER NOTES FOR CHRISTCHURCH – AUTUMN 2018 MARCH While a changeable month, with several troughs crossing over, it was sll drier than normal with above normal temperatures. The first four days were warm, but the warmest day was on the 31 st , in a northwesterly flow. By contrast, the 22 nd was an unusually cold day, as lows to the east and north brought a damp southwesterly flow to the city. Much of the month ’ s rain fell on this day. A thunderstorm affected areas just to the north on the 13 th .

APRIL A month of great variety, with several seled periods, but it also saw a few stormy spells. Tempera- tures varied, with one very cold spell. This, on the 10 th /11 th , brought rain and hail to the city, with snow on Mt Herbert and the upper plains. Aer it cleared, there was a frost on the morning of the 12 th . The 28 th /29 th was also cold and wet, while a southerly change on the evening of the 21 st brought brief thunder and hail. By contrast, the 3 rd (during the morning, before a southerly change) and 6 thth were summery with maximums in the high 20s.

MAY Several airflows from the westerly quarter saw dry, mild weather predominang for large parts of the month, but cold southerlies brought more wintry condions during the last week. The first 10 day was mostly fine, mild weather with high pressure, followed by westerly flows. The 11 th - 16 th brought low pressure to the north and west with onshore flows bringing some (mostly light) rain and drizzle. Then there was a return to westerly flows with dry, mild condions unl the 23 rd . However, the flow tended colder southwesterly from the 23 rd - 26 th , with some showery periods, and hail on the aernoon of the 23 rd . Strong, cold southerlies brought showers and some more hail on the 27 th /28 th , plus snow on the higher Banks Peninsula hills and the foothills. The last three days of the month remained cold under a light southerly flow, but were mostly dry.

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CHOSEN CLIPS IN THE MEDIA FOR AUTUMN

Chosen Media clips for AUTUMN February in Nelson the weest on record 2 March 2018 Nelson Mail Nelson has had the weest February on record, and it looks like the saturaon isn't over yet. Figures taken from Nelson Airport showed 234mm of rainfall for the month. MetService meteorologist Tom Adams said it was 3.7 mes the February average.

"Just for comparison, Blen- heim Airport saw 199mm which is four mes the Feb- ruary normal."

hps://www.stuﬀ.co.nz/nelson - mail/ news/101916312/february - in - nelson - the - weest - on - record

MetService's faulty Whangarei gauge fails to record rainfall for days 7 Mar, 2018

Competors in damp Beach 2 Basin fun run, Sunday. Photo / Tania Whyte Northern Advocate

The Northern Advocate contacted the MetService yesterday aer nocing on its website that no rain had been recorded for Whangarei on Sunday. This was despite atrocious weather and heavy rain mark- ing the Beach 2 Basin event that started at the Onerahi Foreshore on Sunday morning. MetService meteorologist Hannah Moes said it looked like a faulty sensor had not triggered the usual alerts that the system was down, but a technician was being sent to check the equipment. The weather staon, which is inside a louvred box at the airport, sll recorded temperatures and wind speeds over the past week and those ﬁgures are accurate. Rain falls into the rain gauge in the weather staon and the amount in the gauge is measured by sensors, which may be faulty.

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 17

''If it was technical, it wasn't recorded and therefore can't be counted [in the monthly and yearly rainfall totals] and that will aﬀect the rainfall stascs. If it was programming then we should be able to retrieve the data. '' (Abridged) hps://www.nzherald.co.nz/the - country/news/arcle.cfm?c_id=16&objecd=12007482

Around 120 people trapped by Whanganui slips 9 Mar 2018 Guests at a Ruapehu lodge are being evacuated following heavy rain that has "destroyed" the access road. Civil Defence says that 14 of the most vulnerable people were evacuated from Blue Duck Lodge at Whakahoro on Thursday night with the remaining 100 or so guests to be evacuated on Friday. hps://www.newshub.co.nz/home/new - zealand/2018/03/around - 120 - people - trapped - by - whanganui - slips.html

Cyclone Hola expected to hit NZ Monday morning 10 March 2018

Tropical Cyclone Hola as it is expected to look in the early hours of Monday morning. Photo: Niwa The storm is currently near the Loyalty Is- lands, with wind gusts of up to 185km/h, and is heading on a south - southeastward track for the next two days. It is expected to hit the upper North Island on Monday, but MetService said the storm is likely to be less destrucve than cyclones Fehi and Gita because the des will be lower. MetService meteorologist Andy Best says the upper half of the North Island will be worst - aﬀected. (Abridged) hps://www.radionz.co.nz/news/naonal/352246/cyclone - hola - expected - to - hit - nz - monday - morning

Forecasters are predicng the "very fast moving' Cyclone 11 March 2018 As tropical cyclone Hola looms closer to New Zea- land, the storm was causing havoc near New Cale- donia, with gusts up to 185km/h and swells expected to exceed 7 metres. Hola has been downgraded from a category 3 to a category 2 cyclone, though Kiwis are being warned it could sll bring an onslaught of wild weather. The storm was expected to hover to the east of Northland around midnight tonight, before tracking southeastwards on Monday.

MetService meteorologist Amy Rossiter described the storm as "very fast moving".

With the centre of Tropical Cyclone Hola expected to track just to the east of the upper North Island on Monday, areas from Northland to Gisborne

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may have a period of heavy rain -- however, even a subtle shi farther east could leave the plume of moisture oﬀshore.

Tropical Cyclone Warning Centre Wellington (TCWC) took over responsibility from Fiji in the early hours of this morning and is now monitoring and issuing of forecasts on HOLA . Here is the track (past and future) based on latest satellite and computer data. (Abridged) hps://www.odt.co.nz/news/naonal/cyclone - hola - way

DIY weatherman wants to set up his own rival MetService in Wellington region 11 March 2018 Daniel Talbot wants to install a chain of weather staons around the Wellington region to provide a local weather service. Not sasﬁed with the weather reporng in his city, one man – in true Kiwi style – is on a mission to set up his own DIY forecasng service. Upper Hu weather enthusiast Daniel Talbot is hoping to crowdfund a $30,000 weather staon in Upper Hu – the ﬁrst of what he hopes will be a network of staons across the Wel- lington region.

MATTHEW TSO/STUFF Daniel Talbot at the Seymour Grove lookout in Upper Hu, where he wants to put his first weather staon. "It would be local. It's community focused. I want to introduce people to my passion." Talbot already runs a community weather Facebook page Wellington Severe Weather Reports . Upper Hu did not have an "official weather staon" and many exisng services across the region did not provide up - to - the - minute readings or images, he said. A MetService spokeswoman said a NIWA weather staon was already located at Trentham Racecourse and the MetService had an agreement to publish data from that staon. Informaon from the staon was also available to media. Talbot's plan was to build the first staon on a 10 - metre tower at the lookout on Seymour Grove in Up- per Hu, though he had not yet approached the Upper Hu City Council with his proposal. The staon would be built to World Meteorological Organizaon standard with temperature, wind and rain metres. It would also include a lightning tracker and high - definion camera. Talbot's long - term goal was to place about eight staons across the region, though not all would have the same equipment or be built on a tower. Another staon he was keen to get up and running was one at Wellington's Lyall Bay, targeted at serving the surfing community. His Givealile page has raised more than $2100 towards the first staon. Talbot has been a keen weather watcher since he was 15 when snowed fell on his family farm in Kai- toke. He said weather presenter Jim Hickey played a big part in shaping his passion for weather. He found Hickey's enthusiasm infecous. (Abridged)

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 19 hps://www.stuﬀ.co.nz/science/102130806/diy - weatherman - wants - to - set - up - his - own - rival - metservice - in - wellington - region

Cyclone Hola: no longer tropical 11 March 2018 Tropical Cyclone Hola sing to the west of Vanuatu on March 8. Hola will lose its tropical status as it heads towards New Zealand – “ but it could sll be dangerous. ” Tropical cyclones at their peak have a largely cloud - free eye, surrounded with acve thunderstorms. They also stand vercally, like large columns. When they leave the tropics they oen encounter Westerly winds which can whip the top off, and cooler seas, which destroy their feedback loop, MetService meteorologist April Clark said. By the me they hit us, they are just called cyclones, she said. (Abridged) hps://www.stuff.co.nz/naonal/102165997/cyclone - hola - just - as - strong - as - a - tropical - cyclone - but - different

New Zealand says adiós to Hola and hola to a surfers' paradise aer gale - force winds 12 Mar, 2018 The Bay's surﬁng community was not deterred by Cyclone Hola. It was buckeng down about 6pm but the car parks nearest the surf beach beside Mouturiki (Leisure Island) were full. Gale force winds and heavy rain connued to lash the upper North Island overnight, aer a deluge of bad weather set in on Sunday evening. Surfers hit the beach at Mount Maunganui dur-

ing Cyclone Hola. Photo / Mark Robson The ex - tropical cyclone is the third of its kind since the beginning of February, following tropical cyclones Gita and Fehi. (Abridged) hps://www.nzherald.co.nz/nz/news/ arcle.cfm?c_id=1&objecd=12011387

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North Island spared direct hit from Cyclone Hola, despite heavy rain for some 13 Mar 2018 Former tropical cyclone Hola now lies to the east of Gisborne, with most of the weather system over and done with for now. The storm moved east overnight and out to sea, with most of the heavy wind and rain hing oﬀshore.

A satellite image taken about 4.50am, March 13, NZT. Source: JMA/MSC Despite severe gales and heavy rain in Gis- borne city about midnight, Fire and Emer- gency said it had no weather - related callouts. Overnight, some parts of the Gis- borne area received very heavy rain and a river level gauge set up on the Hikuwai Riv- er at Willowﬂat north of Tolaga Bay shows a rise of about 3m. hps://www.tvnz.co.nz/one - news/new - zealand/north - island - spared - direct - hit - cyclone - hola - despite - heavy - rain - some hps://www.radionz.co.nz/news/naonal/352370/east - coast - escapes - worst - as - hola - moves - away

New Zealand Defence Force launches data capturing buoy in Southern Ocean 12 March New Zealand Defence Force crew pay their respects at French sail- or Paul Duris' grave on Campbell Island. Commanding officer of offshore patrol ship HMNZS Wellington Lieutenant Commander Damien Gibbs said MetService launched four driing buoys from the ship during the last leg of a three - phase resupply mission to the sub - Antarcc islands. MetService launched the buoys for the Scripps Instuon of Oceanography, one of the world's oldest, largest and most important centres for ocean, earth and climate science research. Steve Knowles, Network Operaons Manager at MetService, said this marked the first me the new generaon of driing buoys would be used in the Southern Ocean. "These buoys capture data, which is used in predicng sea and weather condions such as atmospheric pressure and sea surface temperature," said Knowles, who is leading a six - member team from the agency. He team is also carrying out maintenance work on the meteorological buildings on Campbell Island. "The buoys also capture the height of waves, which is vital in designing ships that would be operang in the Southern Ocean," Knowles said. On Campbell Island, Department of Conservaon staff and a French naval officer, Aspirant Alex Mois- set, installed a refurbished cross on the grave of French sailor Paul Duris. Duris, 24, died of typhoid during a French expedion to observe the transit of Venus in 1874. (Abridged). hps://www.stuff.co.nz/southland - mes/news/102193322/New - Zealand - Defence - Force - launches - data - capturing - bouy - in - Southern - Ocean

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Cold snap brings snow in South 22 March 2018 Snow is connuing to fall in parts of the South this aernoon, as a cold snap sends temperatures plum- meng. Southern District police said it was snowing heavily around the Crown Range Summit at 3pm.

Photo: Cardrona Alpine Resort The Central Otago District Council said this morning that Danseys Pass Road was re- stricted to 4WD vehicles due to snow. Temperatures have dived with the southerly system ’ s arrival. Dunedin had basked in 25degC warmth at the start of the week but now had a forecast high of just 12degC today. Christchurch dropped 10degC, from 24degC yesterday to 14degC today. . The slow - moving southerly front arrived in Fiordland and Westland early this week, dumping more than 300mm of rain, before slowly moving east across the South Island and north to Taranaki yesterday. (abridged) hps://www.odt.co.nz/regions/cold - snap - brings - snow - south

New Zealand just sweated through its hoest summer on record, a Niwa report shows. 5 March 2018 The naonwide average temperature for the 2017 - 18 summer was 18.8 degrees Celsius, 0.3C above the previous 1934 - 35 record of 18.5C, and a signiﬁcant 2.1C above the 1981 - 2010 averages. Niwa principal forecasng scienst Chris Brandolino said the record - breaking summer was "not too surprising". "Going back to the end of spring, late November, there were strong indicaons that this would be a summer that would be warmer than usual," he said. "We've had really warm ocean temperatures going back to No- vember - and when we have winds coming from the north, more than usual, you're going to get really warm weather. However, I think the diﬀerence - maker is we have climate change now. Our Earth is warmer than it was 20 years ago, 50 years ago, 100 years ago.

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2017 - 18: Kiwi Summer for the Record Books In terms of a diﬀerence from average, only 2017 - 18 and 1934 - 35 in the last 109 years have managed to exceed +1.25°C.

The summer may have been a record - breaker, but the 1934 - 35 summer was more extreme in the context of its me. "In 1934 - 35, that summer was 2.7C above - average," he said.

hps:// www.stuﬀ.co.nz/environment/101996439/it - was - oﬃcially - new - zealands - hoest - summer - on - record

NZ Glaciers looking ‘ Sad and dirty ’ 9 March 2018 New Zealand's glaciers are expected to look "prey pathec" following our hoest summer on record, Niwa says. Niwa sciensts are taking to the skies on Saturday as part of an annual survey of 50 South Island glaciers, but preliminary photos already show them looking "sad and dirty". The survey compares the end of summer snowline which reveals how much of the previous winter's snow remains to contribute to long - term glacial ice accumulaon. "At this me of year we can see the eﬀects of the summer melt but following such an extreme summer the layers really start to peel back and you can see how harsh the eﬀect has been on the glaciers," Niwa climate scienst Andrew Lorrey said.

Brewster Glacier in 2016 (le) and 2017 (right) The glacier is on the Main Divide near the Haast Pass. The survey is undertaken every March at the end of summer.The Niwa team - Lorrey, Trevor Chinn, Dr Huw Horgan, Dr Brian Anderson and PhD student Lauren Vargo from Victoria University - use specialised cameras from a light aircra which takes thousands of photos from different angles. The photos will then be used to build 3D models of glaciers that can be compared year on year to give an accurate depicon of the volume of ice that has changed. Glacier fluctuaons are among the clearest signals of climate change, because they are highly sensive indicators of atmospheric temperature and precipitaon levels. It will be the 40th year the survey is conducted For the first me this year a thermal imaging camera will be used that Lorrey hopes will reveal more about the debris - covered ice. (Abridged) hps://www.stuff.co.nz/environment/climate - news/102123604/nz - glaciers - looking - sad - and - dirty - ahead - of - niwas - annual - aerial - glacier - survey

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Why New Zealand is geng pummelled by a 'perfect storm' of ex - cyclones. 8 March 2018 The third cyclone to venture towards New Zealand since February, Tropical Cyclone Hola , is carving out a southward path. Niwa meteorologist Seth Carrier said the "increased frequency" of ex - tropical cyclones aﬀecng New Zealand this year was unusual. Weather features have been conducive for dragging cyclones from the subtropics and the tropics towards New Zealand," he said. RSMC Nadi Tropical Cyclone Warning Centre showing track of HOLA, in UTC Cyclone Fehi hit New Zealand at the beginning of Febru- ary, Gita struck on February 20 and 21, and Hola is now on its way. "Tropical cyclones really can't steer themselves. They are reliant on other weather features around them to steer them wher- ever they may go." (Abridged) hps://www.stuﬀ.co.nz/ naonal/102102474/why - new - zealand - is - geng - pummelled - by - a - perfect - storm - of - excyclones

Online tools for interacve climate change maps now available 7 March 2018, Greater Wellington Regional Council People interested in how climate change may affect the region can now use a huge range of data to drill right down to its impact on local communies. The data, based on four climate change sce- narios ranging from minor to major changes in emissions across different me periods, covers variables such as rainfall, temperature, hot days, wet days, heavy rain days and potenal evapotranspiraon (drying out rates for plants and soil) deficit. Two versions of the informaon are available, one in GIS layers format for those famil- iar with a more technical tool, and a user - friendlier ‘ story map ’ version aimed at the general public. Users can zoom into the maps at whatever level of detail they desire. How- ever, a cauonary note has been included to remind users that climate informaon is best interpreted as a general ‘ large scale paern ’. The results are based on data provided by NIWA. It uses a six - model average technique called ‘ dynamical downscaling, ’ a process which increases the resoluon of the climate informaon down to the regional scale. The maps can be found at: hps://mapping1.gw.govt.nz/GW/ClimateChange_StoryMap/# (public version) hps://mapping1.gw.govt.nz/gw/ClimateChange/ (professional version) hp://www.scoop.co.nz/stories/AK1803/S00157/check - out - online - how - climate - change - may - affect - your - place.htm

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Australian and NZ weather experts issue joint statement 28 March, 2018 NIWA has joined forces with Australia ’ s Bureau of Meteorology to issue a joint Special Climate State- ment about unusual weather paerns over summer. This is the ﬁrst me the two organisaons have combined to issue a Special Climate Statement to record unusual climatology in an aﬀected region. Its purpose is to document major events and act as a historical record. This statement records a sharp rise in sea surface temperatures in the southern Tasman Sea in Novem- ber, reaching 2 C or more above average over a wide area. The full Special Climate Statement can be found here: www.niwa.co.nz/our - science/climate/publicaons and at www.bom.gov.au/climate/ current/statements/ (Abridged) hp://www.voxy.co.nz/naonal/5/307031

Light shines on UV radiaon research 29 March, 2018 - Sun worshippers may feel the burn next week as sciensts and health professionals from around the world meet in Wellington to discuss the latest research on the effects of UV radiaon. The conference, organised by NIWA, aims to update people from a range of disciplines with a professional interest in UV radiaon. NIWA sciensts will discuss the latest research about ozone and UV radiaon, the effects of changing UV on human health and the environment, and how future climate change may affect ozone and UV. Conference convenor, NIWA emeritus atmospheric radiaon researcher Dr Richard McKenzie, says that "despite an apparent improvement to the ozone layer in recent years, aributed to the success of the 1987 Montreal Protocol, the ozone layer is sll fragile, and recent evidence suggests that climate change may affect future recovery. (Abridged) hp://www.voxy.co.nz/naonal/5/307165

$10 cauliﬂower! Wet weather wreaks havoc on shoppers' budgets 4 Mar, 2018

Cauliflower was $9.99 at New World in Welling- ton yesterday. Photo / Supplied Annee Laird, of Foodstuffs NZ, which owns the New World, Pak'nSave and Four Square brands, said recent wet weather had affected the quality and reduced supply of cauliflower. "It's been raining a lot. Cauliflower don't like the rain. Horowhenua is a horcultural hub, known as the food basket of the lower North Island; it has been severely affected by the unrelenng and extreme weather condions. In a market driven by supply and demand, prices have more than tripled for some of the most affected vegetables. (Abridged) hps://www.nzherald.co.nz/nz/news/ arcle.cfm?c_id=1&objecd=12006117

Cyclone Fehi set to cost more than $39m - ICNZ 21 March, 2018

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The Insurance Council this morning released provisional stats on Cyclone Fehi showing the storm had already cost insurers almost $38.5 million. Cyclone Fehi hit New Zealand on 1 February, causing widespread wind damage and flooding in exposed coastal towns. States of emergency were declared in Dunedin and Buller. Fehi was the second major storm to strike New Zealand in 2018, hing less than a month aer the remnants of an early January storm receded. "We ’ ve had $65.2 million in insured losses from extreme weather events already this year, off the back of two storms in the first quarter of 2018, and we ’ re yet to receive the data for Cyclone Gita," said Graon. (Abridged) hp://www.voxy.co.nz/business/5/306442

Urgent repairs aer 'unbelievable downpour' claims SH1 24 March 2018 Urgent repair work is underway to ﬁx a chunk of road swept away yesterday by rain, Far North mayor John Carter says.

The washed out road south of Pukenui between Whalers Road and Lamb Road. Photo: Facebook / Houhora Big Game & Sports Fishing Club State Highway One 40km north of Kaitaia was washed out at about 4pm yesterday, essenally cung oﬀ about 4000 Far North residents. The water punched a hole in the road about 20m wide and 4m to 5m deep, the Transport Agency said. (Abridged) www.radionz.co.nz/news/naonal/353270/urgent - repairs - aer - unbelievable - downpour - claims - sh1

Can Storms Go Off the Scale? 27Mar 2018 Currently, the Naonal Hurricane Centre (an arm of the Naonal Ocean and Atmospheric Administra- on) provides the Saffir - Simpson Hurricane Wind Scale , which defines the strength of a storm from one to five. The categories are as follows: 1 – Highly dangerous winds, some damage expected

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2 – Highly dangerous winds, extensive damage expected 3 – Significant damage will occur 4 – Disastrous damage will occur 5 – A high percentage of human infrastructure will be completely destroyed To date, this system has served both sciensts and the public well, in documenng the severity of storms and in preparing for their impact. However, the increased stability of modern architectural tech- niques, coupled with the amplified power, duraon and intensity of recent storms, has led to experts in the field quesoning whether a new category should be added in order to prevent storms “ going off the scale Last month, a meeng of climate sciensts and experts in New Zealand posited the idea of adding a category SIX to the SSHWS to account for the fact that mes are changing – both in terms of how we classi- fy things and in weather paerns we are experiencing. For example, the last few years have seen extreme flooding in the UK and formidable cyclones and hurricanes baer other parts of the world. “ Since the scale is now used as much in a scienfic context as it is a damage assessment context, it makes sense to introduce a category six to describe the unprecedented strength 200mph storms we ’ ve seen over the past few years, both globally and here in the southern hemisphere, ” explained climatolo- gist Michael Mann . In parcular, Mann was referring to Hurricane Winston, which hit Fiji in 2016 and remains the strongest cyclone ever to hit the southern hemisphere. However, opponents of the idea have warned against upseng public percepon of storm classifica- on. “ Categories are engaging to the public and its easy for us to understand and communicate the severity of a storm, ” countered Chris Brandolino , chief scienst at New Zealand ’ s Naonal Instute of Water and Atmospheric Research. “ I always encourage us re - evaluang the science, we should always be asking ‘ is what we are doing appropriate for the me? ’ But I think if we are seriously to consider this, it requires a holisc approach; looking at the whole scale, not just adding a category. ” hps://www.envirotech - online.com/news/environmental - laboratory/7/breaking - news/can - storms - go - off - the - scale/45468

Four dead, one missing aer major ﬂooding in Fiji from Tropical Cyclone Josie 2 Apr, 2018 Tropical Cyclone Josie: heavy rain, and strong winds to parts of Fiji. Image / Windy.com Four people are reported to have died and one is missing aer major ﬂooding in Fiji from Tropical Cyclone Josie.

The Category One Cyclone formed on Saturday night near Fiji, bringing heavy rain and strong wind causing major ﬂooding in parts of the country.

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New Zealand MetService meteorologist Stephen Glassey said the cyclone was forecast to track southeast over the next few days but would not aﬀect New Zealand.

Tropical Cyclone Josie is forecast to stay a Category One cyclone Im- age / Fiji MetService hps://www.nzherald.co.nz/nz/ news/arcle.cfm? c_id=1&objecd=12024460

Cyclones highlight climate change 4 April 2018 Flooding in Kaiaua in January this year - Photo: RNZ / Supplied Kaiaua resident Alex Corbe never believed in climate change - but a large storm that hit the Firth of Thames in January, flooding his home and dozens of others, was an eye - opener for him. "I ’ ve been a total non - believer up unl the fact." The storm that flooded Mr Corbe ’ s home was the first major one of 2018 - since then several cyclones have baered the country during a record - breaking summer, prompng 10 civil defence state of emergencies to be declared in the past three months. That ’ s compared to 13 throughout all of last year. The Insurance Council esmates extreme weather has caused $65 million worth of damage - Cyclone Fehi alone cost $39m and the costs from Cyclone Gita have yet to be tallied. Climate Change Minister James Shaw says New Zealand was experiencing the effects of a warming planet and the past summer had created much more discussion around the issue. "It ’ s become a topic of conversaon in a way that it really wasn ’ t before, and it ’ s not just because people are looking at the data, but because people ’ s felt experience is so different. "We ’ re having this extraordinary summer, mulple cyclones, flooding and people are starng to join the dots and going ’ that thing we ’ ve been talking about for some me, climate change, this is what it feels like ’," he says. James says people now accepted climate change was being caused by humans and that more acon was needed to stop it. Niwa meteorologist Chris Brandolino says what had started as a dry summer, with droughts declared in parts of the lower North Island and areas of the south, turned very wet. hps://www.sunlive.co.nz/news/176702 - cyclones - highlight - climate - change.html

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TVNZ1 ’ s weather report 6 April 2008

TVNZ's Dan Corbe has loved the weather since he was a school boy. CHRIS SKELTON Every fortnight, we ask arsts and performers about how some of their most famous work happened. This week, we talk to TVNZ's weather presenter, Dan Corbe, about how he pulls the nightly weather report together - without a script. As a young boy I was fascinated by clouds and weather. New Zealand's locaon midway between the South pole and the equator, surrounded by water, means we get a bit of everything thrown at us. Big storms and severe weather is always excing for meteorol- o g i s t b e c a u s e y o u r e a l l y g e t t o s e e t h e a m a z i n g f o r c e s o f M o t h e r N a t u r e i n a c o n . My work day generally starts around lunchme, somemes earlier depending on the weather. Aer I get dressed into my suit for the day, I get stuck into the weather. I look at all the informaon - radar and satellite data, observaons, computer models - and build a picture in my head of the current situaon and what might happen over the coming days. I also think of the best way to take all the com- plexies of the forecast and put it into an easy to follow and understand story. I'm constantly checking updates - up unl the last minute before we go into the studio. The graphics team make up most of the original weather graphics and I tweak them daily to make a weather show that is the best way to visually show and tell the weather story. With our new augment- ed reality graphics, I spend a lot more me with the graphics team creang the scenes that come to life and move across the studio. No longer working with a green screen hasn't changed that much for me - but it does mean the green es can make an oung from me to me. I am normally in the studio several minutes before the weather slots. I move into the weather pre- senng spot in the news track before the weather or in the ad break. I chat with the studio director be- forehand about our alloed weather show duraon. Somemes because of other things such as breaking news, overruns or underruns we can have different duraons to previously planned. Since all of my weather presentaons are ad - lib (no script) I just adjust what I say to keep to the alloed me. I am given me cues in my ear so I know when me is up. To do my job without wring a script, I look through all the weather informaon throughout the aernoon so I have a great image of the country's current and forecast weather in my head. I have also built the collecon of scenes around that image and weather story, so it all becomes a big weather story that I present in the studio each evening. Things do go wrong somemes. Weather clickers or graphics have played up before, but in the live studio seng you just have to go with the flow and do what you can in the circumstances. hps://www.stuff.co.nz/entertainment/tv - radio/102760074/how - we - made - tvnz - 1s - weather - report

"THE COLD IS COMING." 7 April 2018 This is the ominous warning from MetService, with blistering, cold weather set to blast New Zealand next week. A series of southerly fronts bringing icy - cold air from the Antarcc region will hammer Kiwis with severe weather.

"These weather features will bring gale - force winds, heavy rain and thunderstorms to many places over

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the ﬁrst half of next week, with the main risk of severe weather occurring on Tuesday/ Wednesday," MetService warns. hps://www.newshub.co.nz/home/new - zealand/2018/04/weather - snow - and - thunderstorm - blast - to - freeze - new - zealand.html

Why our sea scorched: NZ's incredible marine heatwave 8 Apr NZ Herald Jamie Morton Sciensts say we've all just experienced an event that would be considered unusual even 30 years from now, when temperatures could be a degree warmer. And they don't expect to see anything like the freak "marine heatwave" that turned the Tasman Sea into a warm bath for a long me. It fired our record - hot summer, melted ice caps and lured swarms of jellyfish to our shores. That the marine heatwave happened in the first place was due to a complex but remarkable mix of circumstances. Marine heatwaves as we know them are created by either stronger - than - normal warm ocean currents - or forced by a dramac set - up in our atmosphere. This was a case of the laer. It was born in November from light winds and easterlies, and more ancyclones than normal to the west and east of the South Island, which effecvely dampened down the usual westerly wind swells coming out of the oceans to our south. In the background was the rare pairing of a strong La Nina climate system in the tropical Pacific - known to drive more ancyclones east of New Zealand - with a posive phase of what's called a Southern An- nular Mode, or SAM. When this effect is posive, the massive storms that rage in the "roaring fores" and "furious fiies" latudes in the southern oceans contract toward Antarcca, instead of in our direcon. The combinaon of those two drivers brought many more ancyclones to the south Tasman Sea and east of the South Island and blocked cold swells surging up from the deep south.

Sea surface temperature anoma- lies that were observed on Janu- ary. Image / Supplied Then, it was only a maer of sunny condions warming up the top layer of the sea. Sea - surface temperatures climbed sharply in the southern Tasman Sea in November, reaching 2C or more above average over a sprawling area between here and Tasmania. They only warmed more in De- cember, hing 2.5C and 4C above average through much of the month.

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Even more dramac observaons included snapper being caught in Doubul Sound for the first me ever, an early - season bluebole jellyfish boom and increased sighngs of sngrays in Otago Harbour, where temperatures eventually rose to 21C at the end of January. Algal blooms and kelp forests declined as warm water fish, not usually found so south, became increas- ingly prominent. Climate scienst Dr Jim Salinger, who plans to carry out a major study into the event, said swimmers and surfers also noted the unusual warmth of the waters around the South Island - a region normally noted for its freezing surf. Salinger noted how the first predicon of the marine heatwave was made in Niwa's December climate outlook, by which me it had already bedded in. Even when it was recog- nised, the heatwave was sll much more powerful than meteorologists could have imagined. Source / Niwa hps://www.nzherald.co.nz/nz/news/arcle.cfm?c_id=1&objecd=12028417

Ocean and Tides workshop an immediate help to Niue 9 April 2018 Alofi, Niue - Niuean communies and businesses that rely on the ocean are pung to use tools and knowledge acquired in March during the Australian - funded Ocean and Tides Workshop, hosted by Niue Meteorological Service. Parcipants from communies, the tourism sector and disaster management services report they are applying new knowledge for improved decision - making and beer results. The 4 - day workshop, which was held from 19 - 22 March, was planned in consultaon with Niue Met Service and facilitated by ocean experts from the Pacific Community (SPC) and the Australian Bureau of Meteorology. It featured two days of technical training for the Niue Met Service Staff followed by two days of ocean stakeholder training and consultaon with a wide range of user groups. In the weeks following the workshop, parcipants have indicated it has already made a difference in their work. Parcipants received training on marine meteorology, technical skills and an introducon to ocean data tools, including de calendars, real - me data from Niue ’ s new de gauge, and the Pacific Ocean Portal – a website that makes ocean temperature, waves, sea level and other key forecast maps and graphs easily accessible. “ We learned in detail about des and the different types of de, and this helps us to improve and provide beer forecasts for Niue, ” says Clemencia Sinoeholo, a Meteorology Trainee Officer at Niue Met Service. Mr Keith Vial is a fisherman, owner of Niue Tours, and Commodore of the Niue Yacht Club. “ Aer the workshop, we immediately started using the de chart for our tour operaons, and we are now including the highest high de and lowest low de for the month as well, ” he reports. “ I am also collang all the relevant informaon from the Ocean Portal to be included in the Niue Yacht Club ’ s website for the coming season. ” Molly Powers - Tora, Coordinator for Ocean Intelligence at SPC, highlighted the benefits of the event say- ing, “ The workshop was parcularly mely since Niue de gauge data has just recently been added to the online Real - me Data Display. This site allows users anywhere with an internet connecon to see the current sea level at Alofi Wharf as well as wind direcon, speed, and water temperature. The fisher- men, tourism operators, conservaon officers, yachters, and emergency management folks were all very excited to learn about this. ” This is the seventh in - country Ocean and Tides Workshop delivered under the Climate and Oceans Sup- port Program in the Pacific (COSPPac). The next workshop will be held in Samoa in May 2018. Since its incepon in 2012, COSPPac has worked to build the capacity of Pacific Island Meteorological Services and other relevant agencies to understand and apply climate, ocean and sea level informaon for the benefit of island governments and communies. The Programme is implemented in partnership by the Australian Bureau of Meteorology, Geoscience Australia, SPC, and the Secretariat of the Pacific Regional Environment Programme (SPREP). www.scoop.co.nz/stories/WO1804/S00046/

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 31

The day the weather won 7 April 2018

On April 10, 1968, 51 people lost their lives in the sinking of the wreck of the Wahine, in what is known as New Zea- l a n d ’ s worst modern - me marime disaster. Fiy years lat- e r , ELISA VOR- S T E R looks back on a tragedy that shook the naon.

The Lyelton - Wellington roll - on roll - off ferry TEV Wahine was the largest ship of its kind in the world when it was completed in 1966. With the Easter weekend approaching in 1968, the pride of the ferry fleet was filled in Lyelton with many passengers planning to spend the holiday with their families. The 734 passengers and crew set sail around 8.40pm on Tuesday, April 9, expecng rough but not unusual condions in Cook Strait, completely unaware they were heading into one of the worst storms ever recorded in New Zealand.

The tropical cyclone Giselle was sweeping south and had collided with a southerly front just as the ship reached Cook Strait, causing exceponally rough condions. At 5.50am on April 10, Captain H.G. Robertson began taking the Wahine into Wellington Harbour in winds blowing at over 50 knots (92kmh) – strong but condions other vessels had coped with before. Things began to go wrong when the ship reached the narrow funnel of the harbour mouth, with the wind speed unexpectedly increasing to 100 knots, and the ship ’ s radar failing. A large wave slammed into the side of the ship, knocking people off their feet and pung the vessel side - on to the waves which pushed it towards Barre Reef, on the western side of the harbour en- trance. Aer 30 minutes of baling fierce waves, Captain Robertson tried to turn the ship around to head back to the relave safety of the strait. With visibility poor, and unaware of his locaon, he ordered full speed astern – and the ship reversed on to Barre Reef. The starboard (right - hand) propeller was knocked off and the port - side engine failed shortly aer. Because of the baering from the storm, many passengers were unaware the ship had hit the reef. Without engines, Captain Robertson ordered anchors to be dropped and waterght doors closed, and the nearby signal staon on Beacon Hill was advised of what had happened. The anchors would not hold, however, and the ship dried up the harbour past Point Dorset. Despite being close to shore, the weather made it impossible for rescuers to reach the ship from land. By 1.15pm, the Wahine was lisng heavily, and the command to abandon ship was given 15 minutes later. Passengers who had been kept in the dark about the seriousness of the situaon were now confused and frightened as they francally tried to make their way to the lifeboats.

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Amid the confusion, people went to the high side of the ship from which it was impossible to launch the lifeboats. Only the four starboard lifeboats could be launched, and crewmen struggled to get as many passengers aboard them as possible. At 2.30pm, the now - abandoned Wahine capsized east of Steeple Rock, sinking in just 11.6m of water. Survivors struggled through the waves to reach the eastern shore of the harbour with 200 reaching safety. But this was where many of the fatalies occurred when people they didn ’ t receive medical aenon fast enough to prevent death from exposure. A massive land, sea and ground search swung into acon at first light on the morning of April 11 to locate any remaining survivors. The storm had died out overnight, and bodies were found smashed on the jagged rocks of Wellington Harbour. Fiy - one people lost their lives that day, with another person dying several weeks later, and a 53rd vicm being acknowledged in 1990 as dying as a result of injuries sustained in the wreck. Masterton man explains confusion among passengers Keith Donovan of Masterton told the Times - Age of the day of his experience on the Wahine and the frenzy which ensued in the final minutes onboard. “ It was a piful sight. “ Old people just throwing themselves into the sea from the top deck. “ Others were leaping into the boats regardless of how they landed. ” Mr Donovan could see the reef looming as he sat aboard the Wahine in the smoke room. “ There was no doubt that she was taking water but there was no panic unl the last 20 minutes when the ship began to list. ” Asked about the reported confusion of passengers going to the wrong side of the ship, Mr Donavan said this could have arisen from passengers not realising the Wahine was travelling backwards. “ It was an experience that I never want to go through again. ” On the morning of the disaster, the inial report in the Times - Age stated the Wahine was driing slowly down Wellington Harbour with both anchors out but was “ in no immediate danger ”. Captain Robertson was described by a Union company spokesman as “ one of the company ’ s most experienced steamer express masters ” and said in radio message to the company that all on board were safe and well. The company had no explanaon at 9.45am for the grounding of the vessel. Meanwhile, the region was isolated as it reeled under the most fierce gale since a disastrous tornado which wreaked havoc over a wide area in 1934. Communicaons with other New Zealand centres were cut, electricity supplies completely disrupted, schools closed, homes flooded and hundreds of trees and branches crashed down over roadways bringing down scores of power and telegraph poles. Masterton resident Ben Iorns told the Times - Age at the me that the gales were comparable to the 1934 hurricane which smashed windows, lied roofs and brought down power poles. He described the storm on April 10, 1968 as “ the worst southerly I can remember in the Wairarapa ”. By 10.30am, most of the region was without power and there were fears of flooding in the lower valley as the rivers connued to rise.

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By 2pm the Wahine had unoﬃcially been reported “ to have her starboard deck underwater ”. Eyewitnesses were terriﬁed as the ship began to lt to one side and passengers lining its rails were seen throwing themselves into the sea. An emergency call had been sent to the sister ship Aramoana to go alongside the Wahine in an aempt to rescue some of its passengers. A reporter watching the events unfold described the ship as “ nearly gone. ” hps://mes - age.co.nz/day - weather - won/

Weather lends authencity to 'Wahine' commemoraon 11 April 2018 by Paul Gorman Otago Daily Times

Among those at the Wellington commemoraons of the 50th anniversary of the Wahine tragedy yesterday, there would have been quite a few who noced the appropriateness of the weather. A freezing southerly gale blowing up the east coast of the South Island, across Cook Strait and directly into Wellington Harbour reproduced, on a much lesser scale, the tempest half a century ago that caused one of the country's worst disasters. On Monday I put out the call to Niwa for any records relang to the Wahine storm. Later in the day I had a note from friend and Niwa spokeswoman Susan Pepperell to say they had found a box containing just that kind of material. Among it was the incredible colour chart of wind, air pressure and des that was drawn five decades ago by, or for, chief engineer A. J. H. Hutchison, of the Wellington Harbour Board, and that features here today. Who says science and art don't mix? Alan Petrie, of Te Anau, says he has graphic recall of Wahine day. `Ì was a student at that me in Wellington and vividly recall the green cicadas plastered over the windows of my flat in lower Tinakori Rd. ``The adjoining power pole had sheets of corrugated iron folded around it - much of this roofing iron had floated down from higher suburbs such as Karori. The roof on the neighbouring dwelling lied and I

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 34 endeavoured to help to put a railway tarpaulin over the gaping hole with lile success - the last sighng of the tarp was of it sailing away towards Parliament. `Òn a lighter note, my only personal loss was a bag of Easter eggs, sent to me by my parents from In- vercargill. Sadly, this small Easter treat went down in the Wahine.'' Trevor Addis, of Mosgiel, says he and his wife, Shirley, were living in Ashburton in 1968. ``We had hired a house at Governors Bay on Banks Peninsula. ``We le home in pouring rain, and on the way we had a puncture on our Holden Special. Luckily there was a garage open at Lincoln to change the wheel. `Ìt was sll raining solid and very windy on arrival at Governors Bay and we seled in. The wind got stronger and stronger, and the power failed, so we had to exist on cold food and keep warm by extended stays in bed or put more layers of clothing on. `Òur children, aged 12, 10, 8 and 3, wondered what was happening, especially when full, small roof tanks started flying over our house and into Lyelton Harbour. We had no way of knowing what was happening in the rest of New Zealand, as we had no radio, but eventually packed up and headed for home several days later. ``The roads were liered with smashed trees, but luckily there was space to get around them. What a holiday to remember.'' Helen, of Kaikorai, wasn't even in New Zealand. `Ì was on a 70 - day trip round Europe and I was in Por- tugal and saw on a newspaper billboard: ``Wahine Disaster''. Those are the only words I can remember. `Ìt gave me a fright because you say to yourself, `do I know anyone on it?'. I knew it was a ship. hps://www.odt.co.nz/opinion/whats - with - that/weather - lends - authencity - wahine - commemoraon

Taranaki tornado: Farmers 'hanging on for dear life' 10 April 2018

Damage le aer the tornado swept through Rahotū this morning. Photo: RNZ / Robin MarnFurther

Rahotū farmer Jordy Mul- len said he and a mate were le "hanging on for dear life" as a tornado passed over the milking shed they were working in at Rahotū this morning. "The tornado came right over the top of our cow shed and then ripped over all the houses and barns starng from the boom of the farm right up the middle," Mr Mullen said. "We were stuck in the vat room and all the windows imploded as it sucked in on us so it was just me and Jake Horington just hanging on for dear life." Police said the tornado went through the town, near Ōpunake southwest of New Plymouth, about 7am. south, about a dozen homes in the Taranaki town of Rahotu have lost their roofs, farm buildings were destroyed and power lines came down. hps://www.radionz.co.nz/news/naonal/354703/taranaki - tornado - farmers - hanging - on - for - dear - life

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I thought, this is it': Taranaki truck driver has harrowing ride in tornado's path 10 Apr, NZ Herald A truckie survives aer driving through a tornado. / Video supplied by Rick Field As he drove into the eye of a tornado with trees and power lines coming down across the road a Tara- naki truck driver thought, "This is it". Rick Field was on his way to deliver a load of ferliser in South Taranaki this morning when he drove right into a passing tornado. Field later told the Herald the ordeal started out as a bit of wind and rain, but quickly began to intensify. Soon enough trees were ﬂying over the road and power lines were coming down. "I was just thinking, 'Where can I hide?'," Field said. "But there was nowhere to hide. I couldn't see where I was going, but you don't know if you are going in or out. I just kept driving." "Once the trees started snapping I thought, 'Woah, this is it'. I thought one was going to come straight down on to the top of the cab." Fortunately Field and his truck came out unscathed, albeit a lile shaken. hps://www.nzherald.co.nz/nz/news/arcle.cfm?c_id=1&objecd=12029626 hps://jalopnik.com/man - driving - through - tornado - proves - new - zealanders - swear - 1825145428

NIWA: Taranaki wind likely wasn't tornado

10 April 2018

Eight properes in Taranaki were damaged by wind today. (Photo / NZ Herald) Forecaster Chris Brandolino told Greg Boyed atmospheric condions were unfavourable for a tornado. "I'd say it's prey unlikely that it was a tornado based on the weather condions of the day, but I wouldn't rule it out enrely." Auckland is expected to feel the brunt of the storm from 7pm to 10pm. Brandolino says it's possible power lines and trees will come down in exposed areas. "We are going to see winds geng close to I would say anywhere from 100 to, some places, 130 kilometres per hour." Signiﬁcant wind gusts are already aﬀecng commuters on the drive home. All ferry services to West Harbour have also been cancelled and replaced by buses. hp://www.newstalkzb.co.nz/on - air/larry - williams - drive/audio/chris - brandolino - taranaki - twister - likely - wasnt - tornado/

Day of Destrucve Storm 10 April 2018 A trough bringing strong winds, thunderstorms, heavy rain and possible damaging tornados was moving east across the North Island late Tuesday morning into the early aernoon. Snow and heavy rain have been falling over swathes of the country, while tornados have been reported in the central North Island. Heavy rain for wide swathe in this forecast for 10am Tuesday from MetService. At 2.30pm on Tuesday there were sll 4360 properes in Taranaki without power. With the severe weather forecast for the rest of the evening it was likely a number of consumers would remain without power overnight.

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Thunderstorms had already caused 6000 strikes in one hour in the region, MetService meteorologist Tom Adams said. Earlier on Tuesday MetService warned of snow, possibly as low as 300 metres in parts of Canterbury, along with heavy snow in the Kaikōura Ranges and Canterbury Plains and High Country, as well as in Otago, Southland and Fiordland.

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NICK WRINCH A snowy day has dawned at Lake Heron in the Ashburton Lakes region. hps://www.stuﬀ.co.nz/naonal/102964197/storm - brings - tornados - thunderstorms - gales - and - snow

As it happened: Storm wreaks havoc across the country 10 April 2018 A Taranaki town was hit by tornadoes, ferry crossings over Cook Strait were cancelled and there are warnings of heavy snow on the Desert Road.

Photo: RNZ

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A low brought snow to the South, and rain, gales, lightning and tornadoes are hing the North Island from the west, cung power to thousands and ripping roofs oﬀ homes. Earlier, tornadoes were spoed in Ōpunake and Naonal Park Village, with Civil Defence reporng widespread damage including houses losing roofs. All passenger ferry crossings across the Cook Strait have been cancelled. hps://www.radionz.co.nz/news/naonal/354631/as - it - happened - storm - wreaks - havoc - across - the - country

Powerful winds causing 'chaos' in Akl, thousands without power 11 April 2018 No planes are being allowed to land at Auckland Airport and power is out across the city as powerful winds struck.

A tree on a car on New North Road in Morningside, Auck- land. Photo: RNZ / Sarah Robson All ﬂights into Auckland Airport are being diverted because of debris on the main runway caused by strong winds.

A screenshot from Counes Power's website showing the ex- tent of their outages.

The centre of a low making landfall in the western North Island (Waikato to South Auckland).

A deepening low is making landfall in South Auck- land at the same me as a southerly is kicking in. Winds are expected to peak between now and the early hours of Wednesday AM at this stage. hp://www.radionz.co.nz/news/ naonal/354696/powerful - winds - causing - chaos - in - akl - thousands - without - power

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'Oﬀ the chart': The windiest place in NZ last night had gusts of up to 213km/h 11 Apr, 2018 The heavy winds in Tuesday night's storm pulled trees down onto cars and homes, with 100,000 homes and businesses losing power. People on the Manukau Heads are picking up the pieces aer being the windiest place in New Zealand last night. The mean wind speed was 126km/h and they had gusts up to 213km/hr. The data, which was recorded at the iconic lighthouse was only around 10km/hr below the all - me record. Brian Hamilton, who is known as the local weatherman, recorded winds up to 160km/h on his property. He said this was the strongest storm in around 13 years, before that it would have been in the 1980s or 1990s. "We are used to the wind, but we don't normally get it that strong. "Pine trees smashed in the area. Iron oﬀ house roofs, power poles snapped, road signs snapped. "It peaked at 9pm and for around half an hour we were geng hurricane - force winds."

Brian Hamilton recorded gusts up to 160km/hr on his property on Manukau Heads.

Hamilton's wind turbine blew itself to bits and his glass balustrade and TV - aerial were destroyed. hps://www.nzherald.co.nz/nz/news/ arcle.cfm?c_id=1&objecd=12030327

North Island Recovers aer massive Storm 11 April 2018 Auckland has been blasted by a terrifying storm. Winds the strength of a category two cyclone have downed trees, powerlines and caused widespread damage across the city.

Around a quarter of properes in the Auck- land region are without power this morning following last night's storm. Around 120,000 properes are currently without power and power companies are working to restore this, says Auckland's Civil Defence. At its peak 182,000 properes were without power. NIWA says its Sky Tower climate staon recorded a peak gust of 146.16 km/h at 9:20 pm on Tuesday. (Abridged) hps://www.newshub.co.nz/home/new - zealand/2018/04/weather - live - updates - auckland - wakes - up - to - massive - storm - damage.html

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Powerful storm strikes New Zealand with damaging winds, tornadoes and ﬂooding 11 April 2018 Northern parts of South Island and North Island felt the brunt of the storm which brought tornadoes, damaging winds, ﬂooding and snow.

Satellite image of the storm near New Zealand Tuesday aernoon, local me. Courtesy of the New Zealand Met Oﬃce. (Abridged) hps://www.accuweather.com/en/weather - news/powerful - storm - strikes - new - zealand - with - damaging - winds - tornadoes - and - ﬂooding/70004650

Hail and snow mark end of golden weather 11 April By George Block Dunedin will remain chilly for the rest of the week aer a southerly blast slammed the door on the city's long hot summer yesterday.

An ambulance crawls through the slush on Stuart St. A short but sharp hailstorm yesterday aernoon caused at least two accidents in Dunedin as many vehicles struggled to maintain tracon. PHOTO: STE- PHEN JAQUIERY MetService meteorologist Ravi Kandula said the southerly would strengthen through much of today, reaching gale force around Otago Peninsula before dying oﬀ this evening. The cold snap has prompted snow and ice warnings for some southern highways today. Mr Kandula predicted frequent showers this morning with snow to 500m liing, but temperatures were unlikely to exceed 10degC unl the end of the week. "This strong cold air mass isn't going anywhere.''

hps://www.odt.co.nz/news/dunedin/hail - and - snow - mark - end - golden - weather

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Almost 80,000 Aucklanders have no power - and some may have none for 3 days 11 Apr, 2018 10:31am Civil Defence director John Dragicevich says the public were well informed and the damage caused came as no sur- prise to him. Vector was aware of nearly 400 outages throughout Auckland, with "extensive" damage to its network from last night's ferocious storm. At its peak 182,000 properes were without power. A Vector spokeswoman said the priority was to restore "crical infrastructure" including hospitals and pump staons before outages that were aﬀecng large groups of customers.

Trees in Henderson Park near Corbans Estate damaged. Photo / Supplied

Staﬀ worked through the night in hurricane - force wind and restored power to about 70,000 customers, Vector said.

Some of the power restoraon work was impeded by fallen trees. Auckland emergency management director John Dragicevich said contractors had been working through the night to remove the trees so work could begin. Weatherwatch forecaster Philip Duncan said “ It was a notch higher than what we were expecng.The area of gales wasn't big but hit Auckland like a "wind tunnel". hps://www.nzherald.co.nz/nz/news/arcle.cfm? c_id=1&objecd=12030334

Our storm explained: A marine heatwave, a wild low, and a sng in the tail 11 Apr, NZ Herald Meteorologists have broken the storm, which also handed Auckland, Wellington and Dunedin their coldest night of the year - into three parts. The 'marine heatwave' Fascinangly, the intensity of the storm could partly be aributed to the same reason our surf was so pleasant to swim in over summer. Since November, sea surfaces around New Zealand, parcularly the Tasman Sea, have been warmed by the biggest marine heatwave seen here in 150 years of records. The marine heatwave was caused by a rare and powerful combinaon of a La Nina climate system, a Southern Annular Mode locked in a posive phase, a series of persistent highs, and the background inﬂuence of climate change.

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As a cold mass of air moved up across the ocean towards New Zealand from Antarcca this week, it met these warmer waters in the Tasman Sea. Riding over those unusually warmer ocean waters created a bigger difference in the system's temperature gradient, Niwa meteorologist Ben Noll said. "The greater the difference in temperature gradient, the stronger the weather system," he explained. It wasn't the first me the big marine heatwave meddled with big weather events that have hit New Zealand. Meteorologists also blamed it for charging up ex - tropical cyclones that slammed into the country over past months. Noll expected what was le of the now - fading heatwave had probably been spent on energising this week's storm. The low from the west As the southerly front rolled up the country from south to north, it also unleashed thunderstorms and high wind gusts. These hit Taranaki and the central North Island especially hard yesterday morning, downing power lines and tearing roofs from homes. Meteorologists sll weren't sure if tornadoes were actually involved, or just thunderstorm down - bursts or "straight - line winds" that might have appeared similar to people on the ground. Aer the front had passed over the middle of the country, there was a brief aernoon lull when the weather improved. But a deepening low was waing in the wings west of New Zealand, and made itself known to people in the evening. When it finally stepped on to the stage, it combined with the southerly front already in play - and most of the drama happened directly over Auckland. At some points, winds over Auckland reached up to hurricane - strength, at more than 200km/hr Met- Service meteorologist Tom Adams shed some more light on the one - two punch that hit the city. "Low pressure systems in the Southern Hemisphere spin clockwise, so if you're slightly to the north of that low, you've not only got western winds, but added to that is the speed of movement of the east - going low." Adams said. The Sng Jet: The polar southerly doused colder areas in snow, and brought the coldest night of the year so far to Auckland, Wellington and Dunedin. Adams said a sng jet occurred at the "mesoscale", or the smaller scale of weather systems. It happened when a zone of strong winds, originang from within the mid - tropospheric cloud head of an explosively deepening depression, were powered up as the jet descended, drying out and evapo- rang a clear path as it dropped.

Roof blown oﬀ his home on Monte Cassino Place, Birkdale. Photo / Bre Phibbs

This evaporave cooling led to the air within the jet becoming denser, which in turn led to an acceleraon of the downward ﬂow. The jet then began to hook around the system's centre - much like the sng from a scorpion's tail, hence the name - bringing more damaging winds. Although that combinaon wasn't necessarily a freak occurrence, Adams said it was rare to have all of those factors converging at once on a major populaon centre like Auckland. hps://www.nzherald.co.nz/nz/news/arcle.cfm?c_id=1&objecd=12030432

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 43 'Hazard fague' may be behind severe weather warnings confusion 16 Apr, 2018

Aer last week's violent storm when winds gust- ed up to 213km/h, bringing down trees and knocking out power to 182,000 people, many Aucklanders have said they weren't properly warned of the event . Communicaons company BlacklandPR director Mark Blackham said government warnings over weather events were confusing the public by being either hyped or completely absent. "The public needs sober, measured advice on hazards like very bad weather. The current situaon is ludicrous; we get warnings of imminent disaster that rarely eventuates, or nothing at all, followed by debilitang weather." A survey by the company last year found half of New Zealanders would rather trust their own judgment than official safety warnings. Blackham said at the me it was due to the "cry wolf effect". "When the disaster doesn't happen, people stop believing it." Non - weather authories needed to moderate their warnings, he said. "The psychology involved in warnings is complex. People are heavily influenced by each other to ratchet up the response." Meanwhile, the country's government - funded weather forecasters are also coming under fire over sending out "confusing" and "compeng" messages over severe weather. MetService said last week it stood by its watches, and that it couldn't have done anything more to warn New Zealanders . "We had weather warnings out for a considerable period of me and before it was a warning, it was in the severe weather outlook," MetService meteorologist Tom Adams said. "We had social media, press releas- es and radio interviews, so every base was covered. However, WeatherWatch analyst Philip Duncan said the message could have been lost due to Met- Service compeng against another government agency, Niwa, for "storm headlines". "No other country on earth has two government forecasters, let alone two aggressive commercial ones, but New Zealand does - and we wonder why the 'official' messaging is now geng diluted and lost." hps://www.nzherald.co.nz/nz/news/arcle.cfm?c_id=1&objecd=12033483

Weather Columnist and geographer Richard Heerdegen dies 25 APRIL A Manawatū geographer with a passion for people, weather and the land has died. Richard Heerdegen wrote the Weather Watch column for the Manawatū Standard for about 20 years unl 2002. He spent more than 40 years studying, researching and teaching with the Massey University geography department and spent six years as chairman of the board behind New Zealand Geograph- ic magazine. He died on Friday, April 13, aged 77, at his home in Ōtaki, unexpectedly and suddenly, a family death noce says. Heerdegen's studies in geography led him to delve into a side - interest in the climate and weather and how they aﬀect people, which he began to share with the wider community through the Weather Watch column in 1984.

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"He had a network of people who willingly took rainfall measurements on their own properes and submied them to Dad monthly, so he could report what was going on in more detail throughout the region," son Greg Heerdegen said.

Weather Watch Manawatū Standard columnist Richard Heerdegen.

"He was a real enthusiast and I will always remember him for coining the term 'sprautumn'. "He would describe Palmerston North as a place that only had two annual seasons – winter and 'sprautumn' – his amalgam of spring summer and autumn. "It was an extended season that perfectly epitomised the not overly hot, not overly cold, not overly calm, somewhat tepid, cloudy, windy and wa- tery weather condions that seemed to prevail in the city for nine months of the year." hps://www.stuﬀ.co.nz/manawatu - standard/news/103317561/weather - watch - columnist - and - geographer - richard - heerdegen - dies

State of Emergency declared in Rotorua aer heavy rain caused widespread ﬂooding 29 April The New Zea- land Civil De- fence has declared a local- ised State of Emergency to help emergency services with evacuaons in Roto- rua this evening. Evacuaons have been taking place in Ngongotaha since 3.30pm. Earlier today, around 32 people were trapped at Rotorua's Agrodome aer a stream running through the property had its banks to burst today. hps://www.tvnz.co.nz/one - news/new - zealand/state - emergency - declared - in - rotorua - aer - heavy - rain - caused - widespread - ﬂooding

Christchurch pelted with 8 months' worth of rain already this year 1 May, 2018 The region had had nearly 400mm rain by May 1, according to MetService ﬁgures, well above the average for the four ﬁrst months of the year.

MetService figures show Christchurch has already had 8 months worth of rain this year. Persistent heavy rain in early January caused rivers to overflow, and caused flooding and road closures in the city, forcing the Christchurch City Council to turn on water pumps as the rain coincided with a

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parcularly high de. Christ- church wasn't the only region that had a soggy start to 2018. A string of storms in the start of this year made for a largely wet but warm climate for the country. Levels were highest - or more than 149 per cent above normal - in the central North Island, the eastern North Island south of Na- pier, Kapi Coast, Nelson, South Canterbury, North and Central Otago and Fiordland.

hps://www.nzherald.co.nz/nz/ news/arcle.cfm? c_id=1&objecd=12042682

Wild winds hit 240kmh in South 9 May 2018 Otago's highest wind gust overnight was 115kmh at Swampy Summit (Dunedin), and in Southland it reached 240kmh at Mid Dome, between Lumsden and Athol. MetService meteorologist April Clark said any winds above 118kmh were considered similar to the strength of hurricane winds. The severe gales were caused by a front moving over the lower South Is- land from the Tasman Sea. They were strongest in exposed central parts of Southland and coastal Otago, and caused damage to trees, powerlines and unsecured structures. She said MetService weather staons also recorded wind gusts up to 107kmh in Gore, 96kmh at Nugget Point, and 91kmh in Invercargill. hps://www.odt.co.nz/regions/southland/wild - winds - hit - 240kmh - south

Weather tower ﬁnally puts Picton on the weather map 11 May2018, The Marlborough Express

RICKY WILSON/STUFF: Picton and Marl- borough Sounds Tourism Group member Helen Neighbour - Cone stands at Waitohi Domain, off Dublin Street, where con- strucon on the weather staon has already begun. For years, the portside town has been ignored, outshone by the likes of Blenheim, Wellington and Nelson when it comes to the daily forecast. Now, it's hoped a new weather staon will li its profile with tourists, by allowing it to appear on the MetService weather maps. Picton and Marlborough Sounds Tourism Group member Helen Neighbour - Cone spearheaded the weather staon idea, and said her husband first came up with it about two years ago. "He used to look at the weather forecast on the television and think 'why are other small towns on the map, but Picton,

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 46 which is important, not menoned?' If added, Picton would not be the smallest town on the MetService map. Reeon, with a populaon of about 1000, was included. hps://www.stuﬀ.co.nz/naonal/103816419/weather - tower - ﬁnally - puts - picton - on - the - weather - map

Southern glaciers shrink aer summer heatwave: VIDEO 12 May 2018 By John Lewis

Following New Zealand ’ s hoest summer on record, Niwa climate sciensts and glaciologists say a recent survey of the South Island ’ s glaciers has revealed a "massive meltback". Survey founder Dr Trevor Chinn said the survey took place in March and showed the summer ’ s marine heatwave had resulted in one of the largest glacier melt seasons observed since flights began in 1977. Since the first survey 40 years ago, sciensts had detected a 30% loss of ice, he said. But Dr Chinn said there was so much melt over the past summer that more than half the glaciers had lost all the snow they gained over the past winter, and some from the winter before. "A glacier is the best climate change indicator you can use," he said. The annual survey forms part of the Climate Present and Past project, which looks at recent and historical data to track past variability and changes in climate. During the survey, conducted from a fixed wing aircra, the sciensts take thousands of photographs to build 3 - D models of glaciers that can be compared year on year. hps://www.odt.co.nz/news/naonal/southern - glaciers - shrink - aer - summer - heatwave hp://www.voxy.co.nz/naonal/5/310416 hp://community.scoop.co.nz/2018/05/video - survey - reveals - massive - meltback - in - nz - glaciers/

Record - breaking 'monster wave' detected in Southern Ocean 14 MAY 2018 MICHAEL D'ESTRIES The notoriously wicked weather of the Southern Ocean recently spawned what researchers are declar- ing was the largest wave ever recorded in the Southern Hemisphere. On the evening of May 9, a weather buoy moored near Campbell Island, a sub - Antarcc island of New Zealand, detected a wave measuring 23.8 meters (78 feet) during the passage of a fast - developing, low - pressure cell. The measurement eclipses the previous record for wave height in the Southern Hemi- sphere, a 19.4 - meter (63 - foot) wave detected in 2017. The buoys, monitored by MetOcean Soluons, are giving researchers unique insights into the incredible storms that rage through this poorly studied part of the world. "The Southern Ocean is a unique ocean basin and is the least studied despite occupying 22% of the global ocean area," Senior Oceanographer Dr. Tom Durrant said in a statement

What's interesng about this parcular wave is that it likely was not the largest. Because the buoy is solar - powered, it only has enough power to measure ocean condions for just 20 minutes every three

Meteorological Society of New Zealand Newsletter153 Winter 2018 Page 47

hours. "It is likely that the peak heights during this storm were actually much higher, with indi- vidual waves greater than 25 m being possible as the wave forecast for the storm show larg- er wave condions just north of the buoy locaon," shared Durrant.

Data collect- ed as the storm passed. (MetOcean Soluons)

The researchers say a low - pressure cell was travelling over the water at the same speed as the waves it was forcing, meaning those waves could grow and grow as they stayed under the influence of the storm. The storm also registered a "significant wave height" of 14.9 metres (48.9 feet) – that's the World Meteorological Organisaon (WMO) standard for measuring the volality of the ocean, and means the average height of the highest third of measured waves. While that's a record for the South Ocean, it pales in comparison to the world record – the highest significant wave height ever recorded was logged in the North Atlanc in 2013, at 19 metres (62.3 feet). And the biggest wave ever recorded? According to Smithsonian , tsunami wave from 1958 that hit Alas- ka's Lituya Bay was recorded at 100 feet (30.5m). Abridged and combined hps://www.mnn.com/earth - maers/climate - weather/blogs/record - breaking - monster - wave - detected - southern - ocean hps://www.sciencealert.com/monster - wave - sets - new - southern - hemisphere - height - record hps://www.heraldextra.com/print - specific/columnists/record - wave - recorded - near - new - zealand/ arcle_28c42cbd - b33a - 579e - 8807 - 80f917c7f69f.html

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Sciensts bring in Alexandra pupils to help with air quality research 22 May 2018

Emily Toxward: Alexandra smog is one of the worst in New Zealand. Pupils at a Central Otago primary school are helping sciensts learn more about polluon in their town in a four - month project that will track where smoke comes from and where it goes over winter. NIWA air quality scienst Dr Ian Longley and his colleagues have teamed up with Year 5 and 6 pupils at Alexandra Primary School to learn more about how smoke from home heang is causing air quality problems in the town and how these problems might be solved. "We need a beer understanding of where and when the emissions occur which we think the school- children can help us with," Longley said. Alexandra is known as one of New Zealand's most polluted towns and regularly exceeds the Naonal Standard for air quality, he said. NIWA had developed a low - cost sensor known as an Outdoor Dust Informaon Node (ODIN) which were usually ﬁxed to power poles and enabled communies to observe, understand and ulmately control their local air quality in a more direct way than previously possible, he said. By the end of winter, NIWA planned to have installed up to 100 ODINs across Alexandra. The ODINs transmied air quality data in real me enabling researchers to build up a picture of how it varied from day to day and place to place, he said. An adapted version of the ODIN, would also be assembled at school and taken home by the pupils for a week at a me to provide a snapshot of what was going on with smoke inside their own homes. In addion, NIWA meteorologist Maria Augus would provide students with weekly video weather forecasts focusing on the connecon between air quality and weather condions. The school project was a government iniave under the Unlocking Curious Minds programme which aimed to encourage and enable beer engagement with science and technology for all new Zealanders. hps://www.stuﬀ.co.nz/environment/104095830/sciensts - bring - in - alexandra - pupils - to - help - with - air - quality - research

Thursday, 24 May 2018 More wild weather aer wintry blast 24 May Much of the country woke up to a bierly cold day on Thursday, with temperatures well into the negaves and snow closing some roads in both main islands and disrupng schools in the South. The Crown Range Road and Milford Road will remain closed overnight on Thursday as a wintry connues to blast the South, with more wild weather on the way. Arrowtown woke to a dusng of snow this morning. Photo: Jeremy Carey - Smith

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Snow fell to 300m about Otago, Fiordland and Southland this morning, MetService said, and more was forecast on the alpine passes and over the southwest of the South Island today and into this evening. The snow also hit the North Island, closing the Desert Road (SH1) between Waiouru and Rangipo. hps://www.odt.co.nz/regions/more - wild - weather - aer - wintry - blast

Auckland April storms cost $72m - 5th biggest storm this century 25 May, 2018 Tamsyn Parker, Money Editor, NZ Herald The April storm which cut power to thousands of Auckland homes for days has cost insurers more than $72 million and could put New Zealand on track for the costliest year for weather - related claims. Fig- ures from the Insurance Council show more than 13,000 claims were made aer the storm hit on April 10 and 11. As hurricane - force winds ripped through the city at up to 140km/h, the storm knocked out power to over 200,000 Auckland properes. Lines company Vector reported that homes were aﬀected for 11 days following the storm. "The 10 and 11 April storm has been the most expensive so far this year and has cost more than cyclones Gita and Fehi combined," Insurance Council chief execuve Tim Graon said. The storm was the fourth storm to hit New Zealand this year and could put the country on track for the most expensive year for weather - related insurance claims. "Last year was the most expensive year on record for severe weather events with $243m in insured losses. "

hps://www.nzherald.co.nz/personal - ﬁnance/news/arcle.cfm?c_id=12&objecd=12058371

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La Nina's gone; wild and unruly arrives

29 May 2018 We've got hot temperatures, we've got cold temperatures, freezing temperatures, ice, snow, hail, rain - and even a few rays of sunshine. And one very confused weather paern. This me last week 15 towns and cies across New Zealand were on track for their warmest May on record. Yesterday, they all fell out of the running. Mr Noll says we are now in limbo - neither La Nina, nor El Nino - which means a lot of ups and downs, and exposure to more variable weather. "Mother Nature dances to the le, dances to the right and then takes a misstep - we're seeing it all at the moment." hp://www.voxy.co.nz/naonal/5/312117

The opportunies climate change will bring to farming 29 May 2018 Adapng and thriving in a changing climate is the focus of Niwa's Fieldays display at Mystery Creek. Us- ing highly detailed computer graphics, farmers will be able to ﬁnd out what climate change might look like on their farm, and explore the choices they face.

Niwa chief climate scienst Dr Sam Dean. We are in the unique posion of knowing what our choices are and I want people to be informed to make decisions based on good science. I do think it's important that we try to understand how much climate change is likely to affect New Zealand in the years ahead. Then, once you understand that significant change is coming, and some of it is now inevitable, planning how we will adapt and thrive in a changing climate becomes a priority. Changes in temperature will affect a range of farm acvies. Crops that require warm climates may be able to be grown in areas currently considered too cool. Harvest mes may be earlier and pasture pro- ducon may increase in southern areas due to an extended growing season. Fewer frosts could mean more producve crops, and those crops may expand to areas currently frost - prone. Some pathogens may become established or harder to control in a changed climate. Rainfall paerns will also change. There will be more rain in the west and south of New Zealand and less in the east and north, reflecng strengthening westerly winds. Extreme rainfall events are likely to become more extreme. This means more rain, more flooding and stronger, more damaging winds. Niwa focuses on providing informaon on climate change impacts at a local scale for future planning in the primary sector. But we also offer services that are designed to help farmers and growers make con- fident and informed operaonal decisions, such as when and where to irrigate, ferlise, spray, harvest and move stock. We believe that opmising current farming pracces is one of the most effecve adap- taon strategies. Farmers are known for their resilience and ability to adapt to changing condions. I'm a great believer in the power of humankind and our ability to innovate and work our way through issues. (Abriddged) hps://www.stuff.co.nz/business/farming/agribusiness/104305160/the - opportunies - climate - change - will - bring - to - farming

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