Fiji Climate Summary December 2019

FIJI METEOROLOGICAL SERVICE ISO 9001:2015 Private Mail Bag (NAP0351) Fiji Climate Summary certified Climate Nadi Airport, Fiji Services Ph: +679 6724888 Fax: +679 6724050 Email: [email protected] December 2019 Also online at: http://www.met.gov.fj

Issued: January 9, 2020 Since : August 1980* Volume 40 : Issue 12 1. IN BRIEF The El Niño Southern Oscillation continued to be in a neu- with 275mm and Natawa with 250mm, all on the same day. tral state during December 2019. The main weather feature Furthermore, Vunisea registered a record breaking Decem- for the month was tropical cyclone Sarai. ber’s daily rainfall for the station since observation began in 1929 with 212mm on the 27th. Tropical depression, TD03F, the predecessor of tropical cyclone Sarai, affected the Fiji group with heavy rainfall on Sarai also resulted in very high intensity rainfall with Qawa th the 26 , especially in the Northern Division. Saqani re- and Vaturekuka in Labasa registering hourly rainfall of ceived 144mm of rainfall, followed by Vaturekuka with 76mm and 65mm, respectively, at 10am (Fiji Standard th 117mm and Udu Point with 116mm, all on the 26 . Time - FST) on the 28th, followed by Monasavu with 64mm at 6pm (FST) on the 27th and Nadarivatu with 56mm at After attaining tropical cyclone intensity on the 27th, Sarai 7pm (FST) on the 27th. Consequently, several places were passed to the west of the Fiji Group, before making an east- flooded. erly turn on the south of Kadavu in the early hours of the 28th, passing through the Lau Group in a southeasterly di- Apart from the rainfall brought by Sarai in the last week of rection and exiting the Fiji Waters by 30th. the month, it was comparatively drier than usual for most part of the month across the country. Tropical cyclone Sarai attained a maximum intensity of Category 2, resulting in storm to gale force winds in several parts of the Fiji Group. The highest sustained wind was at Yasawa-i-Rara with 89km/hr, closely followed by Vunisea with 75 km/hr. The highest wind gust was at Vunisea with 117km/hr, followed by Yasawa-i-Rara with 113km/hr.

Tropical cyclone Sarai resulted in significant rainfall across the country. Monasavu registered 355mm of rainfall on the 27th, followed by Nadarivatu with 327mm, Waikubukubu

2. WEATHER PATTERNS A high pressure system to the far southeast of Fiji directed west with cloud and showers on the 18th. An east to south- an east to southeast wind flow over the group with fine east wind flow prevailed over the group from the 19th till weather apart from brief showers from the 1st till the 4th. the 25th with mostly fine humid weather over the group.

A trough of low pressure affected the group from the west TD03F affected Fiji from the northwest on the 26th with on the 5th and 6th with cloud and showers. An easterly wind heavy rain, strong and gusty winds. On the 27th, TD 03F flow prevailed from the 6th till the 9th with fine weather intensified into a Category 1 tropical cyclone just to the apart from brief showers over most places. northwest of Fiji and was subsequently named Sarai. Gale to storm force winds with continuous heavy rainfall affect- A wind change of south to southwest established over the ed Fiji over the western and southern parts as Sarai tracked group on the 10th till the 12th before it turned southeast on through the Fiji group. the 13th & 14th, resulting in fine weather, apart from brief showers, over most places. Fine weather returned to most parts of the country on the 31st, apart from the Lau group, where it was cloudy with A trough of low pressure affected the group from west on some showers and fresh to strong southerly winds. the 15th and spread to the rest of the group on the 16th , resulting in cloudy periods and showers. An east to southeast wind flow prevailed over the group with fine weather apart from brief showers on the 17th.

A trough of low pressure affected the group from the north-

*Previously known as the Fiji Islands Weather Summary and Monthly Weather Summary 1

Fiji Climate Summary - December 2019 Volume 40 : Issue 12 3. RAINFALL In general, most parts of the country received average or 327mm, Waikubukubu with 275mm and Natawa with above average rainfall during December. Out of the 27 sta- 250mm. Furthermore, Vunisea registered a record break- tions, 4 recorded below average rainfall, 13 average, 8 above ing December’s daily rainfall for the station since observa- average, while Vunisea and Matuku received well above tions began in 1929 with 212mm on the 27th (Table 1). average rainfall (Table 2). At times intense precipitation was registered during the The highest total monthly rainfall during the month was rec- passage of tropical cyclone Sarai with Qawa and Vature- orded at Monasavu with 833mm, followed by Nadarivatu kuka in Labasa registering hourly rainfall of 76mm and with 771mm, Tokotoko (Navua) with 590mm, Lomaivuna 65mm, respectively, at 10am on the 28th, followed by with 554mm and Saqani with 400mm. On the contrary, the Monasavu with 64mm at 6pm on the 27th and Nadarivatu lowest total monthly rainfall was received at Yasawa-i-Rara with 56mm at 7pm on the 27th. with 140mm, followed by Rakiraki with 158mm, Lautoka Mill with 159mm and Momi with 162mm. Koronivia recorded the highest number of rain days (≥0.1) with 26 days, followed by Lomaivuna and Nasinu with Tropical cyclone Sarai and its predecessor tropical depres- both 25, Rotuma and Monasavu with both 24, Nausori sion, TD 03F, resulted in significant rainfall across the coun- Airport and RKS (Lodoni) with both 23. In contrast, Momi try from the 26th to the 29th. Some places registered very registered only 6 rain days, followed by Labasa Airport heavy rainfall on the 26th, especially in the Northern Divi- and Lautoka Mill with both 9, and Rarawai Mill and Viwa sion, whereby Saqani recorded 24-hour rainfall of 144mm, with both 10. followed by Vaturekuka with 117mm, Udu-Point with 116mm and Viwa with 106mm.

As TD 03F intensified into a tropical cyclone on the 27th, rainfall became even more intense. Monasavu registered 355mm of rainfall on the 27th, followed by Nadarivatu with Figure 1

Normal: Long term average from 1971 to 2000 Average: Rainfall between 80 to 119% Well Below Average: Rainfall less than 40% of normal Above Average: Rainfall between 120 to 199% Below Average: Rainfall between 40 to 79% Well Above Average: Rainfall greater than or equal to 200% of normal Rain Day: Rainfall ≥ 0.1mm

Fiji Climate Summary - December 2019 Volume 40 : Issue 12 4. AIR TEMPERATURES A. Maximum Daytime Air Temperatures B. Minimum Night-time Air Temperatures

Generally normal to above normal mean monthly maxi- Normal to above normal minimum air temperatures were mum air temperatures were recorded during the month. recorded at most of the places during the month. Out of Of the 21 climate stations that reported in for the prepa- the 21 stations, 14 recorded anomalies ≥+0.5°C, 5 within ration of this summary, 14 stations reported above nor- ±0.5°C, while Labasa Airfield and Ono-i-Lau were the mal temperatures (anomalies ≥+0.5°C), 6 normal only two stations that had anomalies ≤ -0.5°C (Table 2 & (within ±0.5°C) temperatures, while Udu Point was the Figures 2-5). lone station that registered below normal (≤ -0.6°C) temperature (Table 2 & Figures 2-5). The coolest minimum air temperature on average was at Nadarivatu with 18.4°C, followed by Monasavu with The warmest days on average were at Seaqaqa and Mo- 19.1°C, Labasa Airport with 20.5°C and Keiyasi with mi with both 33.0°C, followed by Keiyasi with 32.9°C, 21.7°C. On the other hand, warmest nights on average Rarawai Mill (Ba) with 32.8°C and Yaqara with 32.7°C. was at Rotuma with 26.9°C, followed by Yasawa-i-Rara On the contrary, the coolest day-time temperatures on with 25.7°C, Viwa with 26.4°C and Nabouwalu with average was recorded at Monasavu with 25.7°C, fol- 24.9°C. lowed by Nadarivatu with 26.3°C, and Vunisea and Matuku with both 29.7°C. The lowest night-time temperature was registered at Na- darivatu with 14.2°C on the 12th, followed by Monasavu Momi registered the highest daily maximum air temper- with 15.5°C on the 1st, Rarawai Mill (Ba) with 17.2°C on ature for the month with 36.9°C on the 29th, followed by the 2nd and Nacocolevu with 17.9°C on the 4th. On the Keiyasi with 36.4°C on the 8th, Rakiraki with 36.0°C on contrary, the warmest minimum air temperature during the 22nd and Nacocolevu with 35.5°C on the 18th. Over- the month was recorded at Rotuma with 28.1°C on the cast condition due to tropical cyclone Sarai resulted in 29th, followed by Yasawa-i-Rara, Savusavu Airfield and maximum air temperatures to fall with most of the sta- Nabouwalu with all 26.6°C. tions registering the month’s lowest minimum air temperature between the period 26th to the 29th. Nadarivatu There was no new minimum air temperature record dur- recorded the coolest day-time temperature with 22.5°C ing the month. on the 28th, followed by Monasavu with 23.0°C on the 29th and Ono-i-Lau with 26.5°C on the 29th.

There was no new maximum air temperature record during the month.

TABLE 1. CLIMATE RECORDS ESTABLISHED IN DECEMBER 2019

Element Station Observed On Rank Previous Year Records (record) (record) Began

Daily Rainfall Vunisea 211.9mm 27th New High 188.7mm 1989 1929

Note: All comparisons in this summary are with respect to “Climatic Normals”. This is defined to be the average climate condition over a 30-year period. Fiji uses 1971-2000 period as its “climatic normal” period, unless otherwise stated.

Fiji Climate Summary - December 2019 Volume 40 : Issue 12 TABLE 2. DAILY CLIMATE REPORTING SITES: SUMMARY FOR DECEMBER 2019 RAINFALL AIR TEMPERATURES SUNSHINE TOTAL RAIN MAX. AVERAGE DAILY EXTREME TOTAL * DAYS FALL MAX. # MIN. # MAX. MIN. * MM % + MM ON C C C C C ON C ON HRS % NADI AIRPORT 202 114 11 126 27 32.5 1.0 23.1 0.7 35.0 14 21.2 1 210 92 SUVA/LAUCALA BAY 294 106 21 111 27 30.4 0.1 24.3 0.8 33.6 14 21.0 1 164 84 NACOCOLEVU 204 113 15 78 27 32.2 1.3 22.1 0.5 35.5 18 17.9 4 121 66 ROTUMA 223 78 24 44 25 31.9 1.2 25.9 1.2 34.6 30 24.8 9 VIWA 258 179 10 105 26 31.9 1.0 25.4 0.4 34.0 12 23.1 16 UDU POINT 294 112 20 116 26 29.8 -0.7 24.5 0.4 31.0 15 22.5 13 SAVUSAVU AIRFIELD 342 132 12 110 12 30.0 -0.2 24.3 1.3 32.0 8 22.5 12 LABASA AIRFIELD 281 116 9 97 28 32.2 0.5 20.5 –1.2 33.5 9 18.5 1 NABOUWALU 256 100 15 99 15 31.1 1.5 24.9 0.9 32.2 9 23.3 16 KORONIVIA 375 143 26 76 27 30.0 0.2 23.1 0.7 32.0 29 19.5 1 NAUSORI AIRPORT 254 95 23 53 27 30.3 0.6 23.2 0.6 32.0 4 20.0 1 NAVUA/TOKOTOKO 590 169 21 143 15 U/S U/S U/S U/S MONASAVU 833 155 24 355 27 25.7 0.7 19.1 0.6 29.9 21 15.5 1 LAUTOKA AES 159 82 9 86 27 32.3 1.3 23.2 -0.1 35.0 18 21.0 1 BA/RARAWAI MILL 194 86 10 93 27 32.8 0.5 22.0 0.3 34.5 8 17.2 2 PENANG MILL 165 62 16 85 26 31.7 1.4 24.1 0.6 32.9 4 21.7 10 MATEI AIRFIELD 185 62 20 63 26 29.9 0.3 23.5 0.6 30.7 15 21.3 13 VANUABALAVU 198 107 14 86 27 U/S U/S U/S U/S LAKEBA 171 95 17 54 17 30.3 0.6 24.1 0.4 31.5 3 21.4 22 YASAWA 140 90 12 84 26 32.6 2.2 25.7 1.3 34.5 10 23.7 24 VUNISEA 388 211 20 212 27 29.7 0.3 23.8 0.9 31.4 7 21.2 12 MATUKU 312 202 16 160 17 29.7 0.0 24.4 0.6 31.5 22 21.5 12 ONO-I-LAU 226 151 12 101 29 30.4 1.7 22.9 -0.6 32.5 22 20.4 1 YAQARA AWS 291 152 12 136 27 32.7 24.6 35.0 8 22.0 10 LEVUKA AWS U/S U/S U/S U/S U/S KEIYASI AWS 325 15 155 27 32.9 21.7 36.4 8 18.0 1 LOMAIVUNA AWS 554 25 97 27 U/S U/S U/S U/S NADARIVATU AWS 771 18 327 27 26.3 18.4 29.3 8 14.2 12 RKS LODONI AWS 376 23 82 27 31.4 24.0 34.8 29 19.8 1 MOMI AWS 162 7 107 27 33.0 23.8 36.9 29 21.5 1 KOROLEVU AWS U/S U/S U/S U/S U/S KORO ISLAND AWS U/S U/S U/S U/S U/S SIGATOKA AWS 213 12 122 27 30.3 22.4 32.8 7 19.1 12 RAKIRAKI AWS 158 14 76 26 31.0 23.9 36.0 22 22.0 31 WAINIKORO AWS 254 17 71 26 31.8 22.9 33.6 22 19.2 23 SAQANI AWS 400 16 144 26 31.5 24.6 33.7 25 22.7 13 VATUREKUKA AWS 318 21 117 26 30.8 22.2 32.6 2 19.0 23 KUBULAU AWS U/S 30.1 23.8 32.3 30 20.7 1 SEAQAQA AWS 217 73 18 92 27 33.0 23.7 35.4 8 19.3 23 DOBUILEVU TB3 280 103 18 97 26 NASINU TB3 278 25 74 27 TAVUA TB3 266 155 11 114 27

TEMPERATURE( C)HUMIDITY WIND SUN RAD DRY WET RH% VP %OF MJ/ MEAN (AVERAGE AT 9AM) KT POS SQ.M NADI AIRPORT 27.8 29.1 24.1 65 26.2 8.2 53 18.3 SUVA/LAUCALA BAY 27.3 27.8 25.0 79 29.6 42 20$ NACOCOLEVU 27.1 28.9 25.2 73 29.0 32 18$ ROTUMA 28.9 VIWA 28.7 UDU POINT 27.2 27.6 25.4 83 30.8 SAVUSAVU AIRFIELD 27.2 28.1 25.2 79 29.8 LABASA AIRFIELD 26.4 28.8 25.2 74 29.3 NABOUWALU 28.0 29.1 25.6 75 30.0 KORONIVIA 26.5 27.7 25.0 80 29.5 NAUSORI AIRPORT 26.7 27.6 24.7 78 28.8 5.8 NAVUA/TOKOTOKO U/S MONASAVU 22.4 22.4 21.0 87 23.7 LAUTOKA AES 27.7 28.4 24.9 74 28.8 BA/RARAWAI MILL 27.4 28.8 24.9 73 28.6 PENANG MILL 27.9 28.5 25.0 75 29.1 MATEI AIRFIELD 26.7 28.3 25.5 79 30.5 VANUABALAVU U/S LAKEBA 27.2 28.6 25.3 76 29.7 YASAWA 29.2 VUNISEA 26.7 27.6 24.8 79 29.1 MATUKU 27.1 27.7 24.6 77 28.5 ONO-I-LAU 26.7 27.9 25.0 79 29.5

MEAN TEMPERATURE IS (MAX+MIN)/2; WIND IS MEAN SPEED AT 06,12,18,24 HOURS. $ :SOLAR RADIATION CALCULATED FROM SUNSHINE DURATION. # :DEPARTURE FROM LONG-TERM AVERAGES (1971-2000). + :NUMBER OF DAYS WITH 0.1 MM OR MORE RAIN. * :PERCENT OF LONG-TERM AVERAGES.BLUE FONT: MISSING RECORDS OF LESS THAN OR EQUAL TO 5 DAYS. U/S: UNSERVICEABLE

Fiji Climate Summary - December 2019 Volume 40 : Issue 12

Figure 2

Figure 3

Figure 4

Fiji Climate Summary - December 2019 Volume 40 : Issue 12

Figure 5 Lakeba (Eastern Division) - Temperature & Rainfall Records for the last 13 Months (December 2018 - December 2019)

Total Monthly Rainfall Long Term Average Rainfall (1971-2000) Monthly Average Maximum Temperature Long Term Average Max Temp (1971-2000) Monthly Average Minimum Temperature Long Term Average Min Temp (1971-2000) 35 600

550 33

500 31 450 29 400

27 350

25 300

Degrees Celsius Degrees Celsius 250 23 Millimetres

200 21 150 19 100

17 50

15 0 Dec-18 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec-19

5. DAILY RAISED PAN EVAPORATION

Daily Evaporation for December 2019 Figure12.0 6

Nadi Suva 10.0 10.0

8.8 8.6 8.5 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 7.7 7.5 7.5 7.3 7.1

6.4 6.2 6.0 6.0 6.0 6.0 6.0 6.0 6.0 5.6 5.3 5.2 5.2 4.7 4.8 4.4 4.2 4.0 4.0 4.0 4.0 3.9

3.6 3.7 Evaporation (mm) Evaporation 3.1 2.7 2.6 2.5 2.4 2.4 2.0 2.0 1.9 1.9 1.6

0.9 1.0 0.7 0.4 0.0 0.0 o/f 0.1 o/f 0.0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Date

Figure 6: The total monthly raised pan evaporation at Nadi Airport was 178.5mm, with the highest daily evaporation of 10.0mm recorded on 19th. Laucala Bay (Suva) recorded total monthly evaporation of 123.9mm, with the highest daily evaporation of 8.5mm on the 22nd.

6. SOLAR RADIATION

Daily Solar Radiation (MJ/m2) for December 2019 Figure 7: The mean daily solar radiation at Nadi 30 Airport during December 2 25 2019 was 18.3MJ/m

2 )

2 compared to 22.3MJ/m 20 over 30 year average 15 (1971-2000).

10 Radiation(MJ/m 5

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Date

Fiji Climate Summary - December 2019 Volume 40 : Issue 12 7. WIND SUMMARY

Figure 8a: The hourly wind observations at Nadi Airport during the month showed southeasterly wind as the most dominant, followed by westerly and southerly winds. While generally light to strong breeze were observed at Nadi Air- port during the month, tropical cyclone Sarai resulted in winds up to gale force.

Figure 8b: The hourly wind observations at Nausori Airport during the month showed easterly winds were dominant, followed by southeasterly then southerlies. Generally, light to strong wind speed were observed at the station during the month, with tropical cyclone Sarai resulting in gale force winds. 7

Fiji Climate Summary - December 2019 Volume 40 : Issue 12 8. SEA SURFACE TEMPERATURE (SST) Figure 9: Normal to above normal sea surface temperature anomalies were present in Fiji Waters during the month.

Source: Data Portal: http:// oceanportal.spc.int/portal/ app.html#climate

9. CLOUD COVER Figure 10: Slightly below normal cloud cover on average were present over in some of the Fiji region during the month (base period: 1981-2010) (Fiji in red circle).

Source: http:// www.esrl.noaa.gov/psd/map/ clim/olr.shtml

10. SEA LEVEL Figure 11: Sea level anomalies of around +10 to 15cm were observed in most of the Fiji Waters during the month.

Source: Ocean Data Portal: http:// oceanportal.spc.int/portal/ app.html#sealevel

11. WIND ANOMALIES Figure 12: Variable wind anomalies of around 0-1.5m/s were recorded in the Fiji region (base period: 1981-2010) (Fiji in red circle).

Source: https:// www.esrl.noaa.gov/psd/map/ images/rnl/sfcwnd_30b.rnl.html

Fiji Climate Summary - December 2019 Volume 40 : Issue 12 12. TROPICAL CYCLONE SARAI Tropical cyclone Sarai affected the Fiji group during the month. It was the 2nd tropical cyclone to form in the Regional Specialised Meteorologi- cal Centre Nadi – Tropical Cyclone Centre’s area of responsibility during the 2019-20 tropical cyclone season. It attained a maximum intensity of Category 2.

A tropical disturbance, TD 03F, was identified to the west of Tuvalu on the 23rd. It continued to develop and it was upgraded to a tropical depression on the 25th. TD03F further intensified and attained tropical cyclone characteristics. Subse- quently, it was named as tropical cyclone Sarai at 1am (Fiji Standard Time - FST) on the 27th, while it was 240km south-southwest of Rotuma.

Tropical cyclone Sarai tracked south to the west of the Fiji group on the 27th as a Category 1 trop- Figure 13: Track map for tropical cyclone Sarai. The time on the track ical cyclone and intensified into a Category 2 map are in Fiji Daylight Saving Time. system at 4pm on the 27th about 220km west of Nadi. It took a southeast turn at 1am on the 28th towards south of Kadavu. Sarai continued to track in the southeast direction and it was about 110km southwest of Matuku at 10am (FST) on the 29th. It continued its journey as a Category 2 system through the southern Lau Group with the east-southeast move- ment, before exiting the Fiji Waters on the 30th (Figure 13).

The extent of tropical cyclone Sarai was quite huge, with the outer cloud bands continuing to have an impact for several days after the passing of the cyclone eye close to a locality, especially on Vanua Levu and Viti Levu.

Figure 14: Satellite image of tropical cyclone Sarai at 3.30pm (FST) on the 27th. Image source: Himawari-8 satellite.

Tropical cyclone Sarai resulted in gale to storm force winds at several places in Fiji. The highest observed sustained wind was at Yasawa-i-Rara with 89km/hr, closely followed by Vunisea with 75 km/hr, Ono-i-Lau with 73km/hr and Nadi Airport with 71km/hr. The highest wind gust was at Vunisea with 117km/hr, followed by Yasawa-i-Rara with 113km/hr, Nadarivatu with 112km/hr and Nadi Airport with 107km/hr (Table 3). Figure 15: Tropical cyclone Sarai at 8.30pm (FST) on the 27th captured on the radar network in Fiji. Station Maximum sustained wind Maximum wind gust Yasawa-i-Rara 89km/hr at11.10am on 27th 113kmhr at 11.20am on 27th Vunisea 75km/hr at 3.20am on 29th 117km/hr at 2.30am on 29th Ono-i-Lau 73km/hr at 4.10am on 30th 102km/hr at 4.10am on 30th Nadi Airport 71km/hr at 7pm on 27th 107km/hr at 8pm on 27th Nadarivatu 66km/hr at 9.50pm on 27th 112km/hr at 9.20pm on 27th Levuka 63km/hr at 10.30pm on 28th 101km/hr at 10.50pm on 28th Rakiraki 62km/hr at 8.20am on 28th 80km/hr at 3.50am on 27th Table 3: Significant winds observed during the passage of tropical cyclone Sarai. All time are in FST.

Fiji Climate Summary - December 2019 Volume 40 : Issue 12

Figure 16: Maximum 24-hour rainfall during the passage of tropical cyclone Sarai between 26th and 29th. Tropical cyclone Sarai resulted in significant rainfall across the country. Nadarivatu registered 327mm of rainfall over a 24-hour period on the 27th, followed by Waikubukubu with 275mm, Natawa with 250mm, Monasavu with 225mm, Vunisea with 212mm and Tubenasolo with 206mm, all on the same day (Figure 16).

Sarai also resulted in very high intensity rainfall with Qawa and Vaturekuka in Labasa registering hourly rainfall of 76mm and 65mm, respectively, at th 10am on the 28th, followed Figure 17: Flooded Naqali flat in Naitasiri on the 28 . Picture source: Fiji Government. by Monasavu with 64mm at 6pm on the 27th and Nadarivatu with 56mm at 7pm on the 27th. Consequently, several places were flooded.

While the initial damage assessment indicated damage to critical infrastructures were minimal, tropical Sarai disrupted services for water supply, electricity, public transport and road accessibility. Damages to agricultural commodities may- be substantial in some areas. Flights and sailing plans were also cancelled due to the adverse weather conditions. At the time of the production of this report, unfortunately there were two confirmed causalities of tropical cyclone Sarai, one in Naitasiri and the other in Kadavu, both victims of drowning (Information source: National Disaster Management Office).