Monthly Weather Review New South Wales November 2009 Monthly Weather Review New South Wales November 2009 The Monthly Weather Review - New South Wales is produced twelve times each year by the Australian Bureau of Meteorology's New South Wales Climate Services Centre. It is intended to provide a concise but informative overview of the temperatures, rainfall and significant weather events in New South Wales for the month. To keep the Monthly Weather Review as timely as possible, much of the information is based on electronic reports. Although every effort is made to ensure the accuracy of these reports, the results can be considered only preliminary until complete quality control procedures have been carried out. Major discrepancies will be noted in later issues. We are keen to ensure that the Monthly Weather Review is appropriate to the needs of its readers. If you have any comments or suggestions, please do not hesitate to contact us: By mail New South Wales Climate Services Centre Bureau of Meteorology PO Box 413 Darlinghurst NSW 1300 AUSTRALIA By telephone (02) 9296 1555 By email [email protected] You may also wish to visit the Bureau's home page, http://www.bom.gov.au. Units of measurement Except where noted, temperature is given in degrees Celsius (°C), rainfall in millimetres (mm), and wind speed in kilometres per hour (km/h). Observation times and periods Each station in New South Wales makes its main observation for the day at 9 am local time. At this time, the precipitation over the past 24 hours is determined, and maximum and minimum thermometers are also read and reset. In this publication, the following conventions are used for assigning dates to the observations made: Maximum temperatures are for the 24 hours from 9 am on the date mentioned. They normally occur in the afternoon of that day. Minimum temperatures are for the 24 hours to 9 am on the date mentioned. They normally occur in the early morning of that day. Daily rainfall is for the 24 hours to 9 am on the date mentioned. This means a significant fraction of the rain may have occurred on the previous calendar day. Monthly rainfall is for the period from 9 am on the last day of the previous month to 9 am on the last day of this month. Maximum daily wind gusts are in the 24 hours from midnight to midnight. Climatological values The climatological averages shown in the text and tables are generally long-term means based on observations from all available years of record, which vary widely from site to site. They are not shown for sites with less than 20 years of record, as they cannot then be calculated reliably. Climatological extremes are generally taken from available observations from all available years of record. The number of years can vary substantially from site to site. Copyright © Commonwealth of Australia 2009 This work is copyright. You may download, display, print and reproduce this material in unaltered form only (retaining this notice) for your personal, non-commercial use or use within your organisation. Apart from any use as permitted under the Copyright Act 1968, all other rights are reserved. Requests and inquiries concerning reproduction and rights should be addressed to Commonwealth Copyright Administration, Attorney General’s Department, Robert Garran Offices, National Circuit, Barton ACT 2600 or posted at http://www.ag.gov.au/cca. Product code IDCKGC25R1. Prepared on 21 December 2009. ISSN 1836-3067 Cover photograph Red dawn in Sydney. The Sydney Harbour Bridge obscured by a duststorm which reduced visibility to 400 metres. Air traffic was disrupted and harbour ferries suspended during Sydney's worst duststorm since 1942. Photograph by Andrew Treloar, 23 September 2009. Used with permission. If you have a photo you think would make a good cover for the Monthly Weather Review, please contact us at the address above. Monthly Weather Review New South Wales November 2009 Overview NSW experienced its hottest November on record Extremes in November 2009 with a statewide average maximum temperature anomaly of +5.2 °C. A prolonged heatwave from Hottest day about the 8th to the 22nd saw many new (Highest daily maximum temperature) temperature records set for both extreme and 46.8 °C at Wanaaring on the 20th duration. Duststorms and bushfires became more Warmest days on average widespread as temperatures and winds increased (Highest mean daily maximum temperature) during the heatwave. Following a dry October, 37.5 °C at Collarenebri November was also very dry over the central NSW Coolest days on average and southeastern districts. However, in sharp (Lowest mean daily maximum temperature) contrast, very much above average rainfall was 16.0 °C at Thredbo AWS recorded in the far west of the state and on the Mid Coldest day North Coast, where the Coffs Harbour area recorded (Lowest daily maximum temperature) its 5th flood this year. Despite local heavy rainfall, 5.0 °C at Thredbo AWS on the 30th 74% of the state remained in drought during Coldest night November. (Lowest daily minimum temperature) • hottest on record for average maximum −4.8 °C at Charlotte Pass on the 5th temperatures Coolest nights on average • hottest on record for average minimum (Lowest mean daily minimum temperature) temperatures 4.3 °C at Charlotte Pass • severe heatwave 8th to 22nd Warmest nights on average • above average rainfall in west and Mid North (Highest mean daily minimum temperature) Coast, dry elsewhere 22.1 °C at Tibooburra Post Office • 7th consecutive month with above average Warmest night maximum temperatures (Highest daily minimum temperature) • 8th consecutive November with above average 33.3 °C at White Cliffs AWS on the 19th minimum temperatures Wettest overall • inland duststorms, bushfires in east, floods on (Highest total rainfall) Mid North Coast 621.0 mm at Coffs Harbour (Perry Drive) Driest overall (Lowest total rainfall) 0.2 mm at Kenebri (Cumbil)(NW Plains) 2.2 mm at Hermidale (Hermitage Plains) (CW Plains) Wettest day (Highest daily rainfall) 394.5 mm at Coffs Harbour (Perry Drive) on the 7th Highest wind gust 109 km/h at Cowra Airport and Forbes Airport AWS on the 26th page 1 Monthly Weather Review New South Wales November 2009 Significant weather 19th and 20th November - strong westerly winds caused duststorms and raised dust in southwest Severe thunderstorms NSW. Visibility only 200 metres reported at White 2nd November - heavy rain, strong winds and hail up Cliffs, Broken Hill, Menindee and Deniliquin. Wagga to 3 cm size at Katoomba, Central Tablelands. Wagga (South West Slopes) reported raised dust all day and visibility 3 km; at Tocumwal (Riverina) 5th November - severe thunderstorm with hail up to visibility was reduced to 1 km. marble size covering ground 'like snow' at Stanthorpe and surrounding areas on the 21st November - smoke and raised dust at Coffs Queensland-NSW border. Report from flood alert Harbour reduced visibility to 1500 metres. station at Upper Darkwood (Mid North Coast) of 18 mm in 10 minutes from storms. Nearby Dorrigo 22nd November - strong southwesterly winds and reported 47 mm in 30 minutes. raised dust reported at White Cliffs, Ivanhoe and Hillston in western NSW. 6th November - very heavy rain at Utungun (Mid North Coast) with 44 mm falling in 30 minutes. At 25th November - raised dust at Menindee (Lower nearby Mount Seaview, 81 mm recorded in 6 hours Western). with local flooding and rapid river rises. At Coffs 26th November - duststorm and downburst Harbour Airport, 97 mm was recorded in 1 hour with associated with a thunderstorm at Cowra (Central 258 mm in 4 hours. West Slopes) and Parkes with gusts reaching 109 km/ 7th November - very heavy rain in Coffs Harbour h. Strong winds and raised dust reported at Gundagai area caused local flash flooding. There was minor to and Grenfell (South West Slopes). moderate flooding in the Orara, Nambucca, Hastings 27th November - duststorms in parts of the Lower and Bellinger Rivers and Coffs Creek. Highest 24 hour Western. The Broken Hill area reported visibility rainfall was 394.5 mm at Coffs Harbour (Perry Drive) under 3 km. on the 7th. 28th November - duststorm at White Cliffs in the 17th November - hail 2−3 cm size at Murwillumbah Upper Western. and Mullumbimby on the North Coast. Reports of houses damaged by lightning at The Channon (near 29th November - westerly winds associated with an Lismore). Hail was also reported at Guyra on the intense low pressure system caused widespread Northern Tablelands. raised dust extending from Cobar in the Upper Western to the Hunter, Central Coast and Sydney 20th November - severe lightning with thunderstorm Metropolitan. Visibility reduced to 3 km at Cobar, 4 in Sydney. Two houses caught fire after being struck km in Sydney but as low as 200 metres at Jerrys by lightning. A downburst at Church Point, Bayview Plains and 900 metres at Murrurundi (both Upper and Newport (northern Sydney) caused considerable Hunter). damage to houses and brought down trees, prompting 90 calls for assistance to the State Flooding Emergency Service (SES). Boats on moorings were 6th to 7th November - a near stationary surface blown onto their sides during the squall with trough, an upper cold pool of air and very moist low estimated wind speeds of 110 km/h. Also some level easterly winds caused locally very heavy rain on damage from strong winds in Liverpool - the Mid North Coast. Moderate flooding was Campbelltown area in southwest Sydney. reported in the Orara, Nambucca and Bellinger Thunderstorm, small hail and strong winds at Rivers with minor flooding in the Hastings River and Cessnock (Hunter) caused minor damage prompting Coffs Creek. The Orara peaked at 9.0 metres at 20 jobs for the SES.