Monday 28 February 2011

Media Release - Victoria Regional Office


Wettest Summer on record in Victoria

The summer of 2010-11 has been the wettest in Victoria since records began, said Victorian Climate Services Manager Dr Harvey Stern.

"With final data still to be processed in the coming days, Victoria has already received a statewide averaged rainfall total in excess of 300 millimetres for the season," said Dr Stern.

This breaks the previous record for the highest summer rainfall in Victoria of 237 millimetres, set 100 years ago in 1910-11. The average summer rainfall in Victoria is 121.1 mm.

Gippsland is the only area of the state to record near normal rainfall totals for the season.

Victoria endured significant rainfall and flooding events during each of December, January and February. These events contributed to the state recording its:
  • 5th wettest December on record, and wettest since 1992
  • Wettest January on record
  • Wettest February since at least 1973, and provisionally the 6th wettest on record.

Daytime maximum temperatures were below average across Victoria this summer, while overnight minimum temperatures above average. Additionally, there were also a below average number of very hot days and very cold days for the season.

In Melbourne, the maximum temperature exceeded 40 degrees on two occasions during the summer - on December 31 and February 1.

"Australia is feeling the effects of one of the strongest La Niņa events ever observed," said Dr Stern. The last time such a strong La Niņa occurred was in 1973-74.

Ocean temperatures around Australia are near record high levels, and this summer has seen more frequent low pressure systems over Australia as well as much cloudier and more humid conditions than usual.

La Niņa events are typically associated with higher than average spring and summer rainfall over eastern Australia.

"The very strong La Niņa is the primary cause of the very wet summer we have had," said Dr Stern.

"Whilst any one such event cannot be attributed to global climate change, a recent study of extreme weather events across the globe suggests that there has been an increase in the frequency of such events over recent decades, and this trend is consistent with what we expect under global climate change."

The current La Niņa event is now past its peak and will continue to gradually decay during autumn. Bureau of Meteorology computer models suggest a return to more neutral conditions later in the year.

With the La Nina event weakening, rainfall across Victoria during autumn 2011 is likely to be close to normal. However ocean temperatures around Australia are still high, and so maximum and minimum temperatures are likely to be above average during autumn.


Media contact:

Dr Harvey Stern, Manager,
Climate Services Centre (Victoria)
03-96694949(Office)
0459816208(Mobile)


Summer 2010-11 in Victoria: Key Facts and Figures

Summer 2010-11 total rainfall:Provisionally 300-320 mm
Average total rainfall: 121.1 mm
Previous highest summer rainfall:237 mm (in 1910/11)

This summer has broken a 100-year old record.

Hottest Day:43.3 °C at Hopetoun Airport on 31 Dec 2010
Coldest Night:-4.4 °C at Mount Hotham on 28 Dec 2010
Maximum temperatures:Below average
Minimum temperatures:Above average
Number of very hot days:Less than normal
Number of very cold days:Less than normal
Humidity:Above average
Cloudiness:Above average

January Rainfall and Flood Event:

  • West and north of the state received its average summer rainfall in just 6 days
  • 53 rainfall stations recorded their highest ever daily January rainfall in the 24 hours to 9am January 14
  • Near record level humidity across the state
Highest rainfall totals during event:
24 hours to 9 am local time, January 2011.
Station NameMon, 10Tue, 11Wed, 12Thu, 13Fri, 14Sat, 15Total(mm)
HALLS GAP4.60.4135.00.2146.60.0286.8
GRAMPIANS6.81.4134.63.4132.80.0279
KYNETON4.628.632.8109.088.010.8273.8
CANARY ISLAND110.049.039.212.560.00.0270.7
ANNUELLO75.659.234.016.076.60.0261.4
NYAH127.012.028.420.270.00.0257.6

February Rainfall and Flash Flood Event:

  • Mildura recorded its highest ever daily rainfall for any time of year (147.4 mm) on February 5
  • Southeastern suburbs of Melbourne received widespread rainfall totals of between 100 and 150 mm from severe thunderstorms on Friday 4 February
  • Very high and sustained humidity levels across Victoria
Highest rainfall totals during event:
24 hours to 9 am local time, February 2011.
Station NameFri, 04Sat, 05Sat, 06Total(mm)
FALLS CREEK40.4104.261.6206.2
MOUNT HOTHAM35.090.873.2199.0
MOUNT BULLER63.247.884.0195.0
LYNDHURST2.4179.68.0190.0
GEMBROOK18.4124.046.8189.2
CARDINIA RESERVOIR2.8169.016.4188.2
PAKENHAM UPPER3.2158.820.0182.0
IONA5.6151.421.8178.8
MILDURA AIRPORT0.0147.431.4178.8

Victorian Rainfall Totals during Summer 2010-11 (up to Sunday 27 February 2011):


Victorian Rainfall Totals - Summer 2010-11 (up to Sunday 27 February 2011)

Victorian Rainfall Totals during an AVERAGE Summer (based on 1961-1990 average):


Victorian Rainfall Totals during an AVERAGE Summer (based on 1961-1990 average)