Friday 15 January 2010

MEDIA RELEASE

First Heatwave for Adelaide in 2010

Large parts of South Australia experienced an extended period of very hot conditions during the second of week of January with Adelaide recording its first heatwave of the new decade.

Adelaide recorded an unbroken run of 5 consecutive days in excess of 35°C with 4 of these days exceeding 40°C.

The definition of a heatwave for Adelaide is five consecutive days at or above 35°C, or three consecutive days at or over 40°C. This definition is only applicable to Adelaide since climatic norms differ across the state.

The extended run of heat across South Australia was caused by the persistence of low pressure troughs across central and western parts of Australia combined with higher pressures to the east of the state. This resulted in hot east to northeast winds across most areas of South Australia between 7 to 11 January. During 11 and 12 January the westernmost trough pushed across the state bringing cooler conditions and widespread rainfall, mostly between 5 to 20mm.

9 heatwaves were recorded in Adelaide between 2000 through to 2009 and this is the highest decadal total since 1880. This last heatwave is the first of a new decade. The previous highest was 8 heatwaves recorded in each of the decades between 1900 to 1909 and 1930 to 1939. An analysis of observations from Adelaide back to 1880 shows in the 11 decades prior to 2000 there were only a total of 49 other heatwaves recorded.

Local contacts:
Darren Ray, Senior Meteorologist, South Australian Climate Section, Bureau of Meteorology (08) 8366 2664
Paul Lainio, Public and Marine Officer, Bureau of Meteorology, 0417 886 850