Monthly Weather Review Queensland December 2010 Monthly Weather Review Queensland December 2010 The Monthly Weather Review - Queensland is produced twelve times each year by the Australian Bureau of Meteorology's Queensland Climate Services Centre. It is intended to provide a concise but informative overview of the temperatures, rainfall and significant weather events in Queensland 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 Queensland Climate Services Centre Bureau of Meteorology GPO Box 413 Brisbane QLD 4001 AUSTRALIA By telephone (07) 3239 8700 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 Queensland 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. Mean temperatures are the average of the daily maximum and daily minimum temperatures. 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 9 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 2011 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 IDCKGC24R1. Prepared on 21 January 2011. ISSN 1836-3075 Cover photograph Thunderstorm anvil with mammatus at Burleigh Heads. Photograph by Tony Auden, October 2007. 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 Queensland December 2010 Overview • The wettest December on record Extremes in December 2010 • One of the most significant floods in Queensland's history Hottest day • Record flooding across southern and central (Highest daily maximum temperature) catchments 43.2 °C at Birdsville Airport on the 15th • Queensland's first cyclone of the season, Tasha, Warmest days on average crossed the coast south of Cairns on Christmas (Highest mean daily maximum temperature) morning 37.8 °C at Urandangi • Severe thunderstorms with large hail in the Coolest days on average southeast (Lowest mean daily maximum temperature) • There were 82 high daily rainfall and 321 high 22.6 °C at Applethorpe total monthly rainfall records Coldest day • There were 16 low daily and low mean maximum (Lowest daily maximum temperature) temperature records 16.5 °C at Applethorpe on the 19th • There were 6 high daily and mean minimum Coldest night temperature records (Lowest daily minimum temperature) Queensland experienced yet another month of 3.7 °C at Applethorpe on the 21st widespread rainfall under the influence of a strong Coolest nights on average La Niña, following the wettest spring on record. (Lowest mean daily minimum temperature) Flooding continued across many southern and 14.4 °C at Applethorpe central Queensland river systems. Many significant Warmest nights on average weather systems affected the state, bringing (Highest mean daily minimum temperature) torrential rainfall at times, and severe thunderstorms 26.5 °C at Willis Island battered the southeast coast between the 15th and Warmest night 18th. A weak category one tropical cyclone, Tasha, (Highest daily minimum temperature) crossed the coast south of Cairns early on Christmas 29.4 °C at Birdsville Airport on the 31st morning and continuing active monsoonal activity 29.0 °C at Mornington Island on the 20th led to a wet Christmas period that culminated in Warmest on average overall some of the most widespread and significant (Highest mean temperature) flooding in Queensland's history. 30.2 °C at Birdsville Airport 30.0 °C at Century Mine Coolest on average overall (Lowest mean temperature) 18.5 °C at Applethorpe Wettest overall (Highest total rainfall) 1221.2 mm at Bellenden Ker Top Stn 1200.0 mm at Mount Charlton Driest overall (Lowest total rainfall) 2.0 mm at Birdsville Airport Wettest day (Highest daily rainfall) 339.0 mm at Happy Valley on the 25th Highest wind gust 107 km/h at Winton Airport on the 7th page 1 Monthly Weather Review Queensland December 2010 Significant weather Synoptic summary Tropical cyclone Tasha At the beginning of December a slow moving Queensland's first cyclone of the 2010/11season, high-pressure system over the Tasman Sea extended Tasha, formed early on Christmas morning near a ridge along the east Queensland coast, a surface Agincourt Reef to the east of Cairns and crossed the trough lay through the western interior and an upper coast at about 5:30 am south of Cairns between the trough was approaching the state from the west. townships of Gordonvale and Babinda. It was a weak Moisture laden northeasterly winds extending to the category one system but brought significant rain to a inland trough and an unstable upper atmosphere broad area of northern Queensland. resulted in showers, thunderstorms and rain areas developed across most of the state. Widespread rain Very extensive flooding areas with some heavy falls persisted for the next Following very extensive and heavy rainfall periods two weeks, as a series of upper troughs moved during the previous few months, river catchments through the state, enhancing existing flooding or were overwhelmed by further rainfall in December triggering new flooding in many river systems. The that culminated in some of the most widespread and development of several near coastal surface troughs significant flooding in Queensland's history. also enhanced the rainfall and moderated local Theodore and Condamine were fully evacuated and winds. Fine conditions returned to western 22 towns and over 200,000 people were affected. Queensland and gradually spread east as the final Forty-one local government areas were disaster upper trough cleared the coast, though shower declared with significant disruption to mining, activity persisted along parts of the east coast and agricultural and other industries expected to cost showers and storms over the northern tropics. Two many hundreds of millions of dollars. of the heaviest daily falls during this period were at Escott Station in the southern Gulf of Carpentaria Special Climate Statement 24 has further details on where 266 mm was recorded on the 11th from a line the widespread flooding across eastern Australia in of slow moving storms and at Mount Charlton with Dec 2010, and is available on the Bureau's web site 228 mm on the 3rd. at www.bom.gov.au/climate/current/statements. On the 15th the upper trough was offshore but upper Abnormally high tides temperatures remained cool and surface moisture Some parts of southeast Queensland had tides remained high in the east, making conditions 20−30 cm above the normal expected tide before unstable. A surface trough entered the far south west Christmas, easing off further north. This extra height and moved slowly east and scattered showers and pushed the tides above the high water mark on the thunderstorms developed to the east of the trough in highest tide of the day. The majority of this anomaly the south over the next few days. Severe storms is thought to be related to La Niña when stronger produced large hail, damaging wind and torrential than normal trade winds act to pile up water on the rain in the southeast during the 15th and 18th. western side of the Pacific. These high tides were not During the 17th a surface trough moved east into King tides. south-east Queensland. The following day a trough moved north along the southern Queensland coast Severe wind gusts and, combined with mid-level instability, triggered The strongest wind gust was at Winton Airport with showers and thunderstorms from north-west 107 km/h on the 7th, followed by Double Island Queensland to the southeast.