Historic heat wave brings Australia its hottest average temperature on record
It's been a summer like no other in the history of Australia, where a sprawling heat wave of historical proportions is entering its second week. Monday, January 7, was the hottest day in Australian history, averaged over the entire country, according to the Australian Bureau of Meteorology. The high temperature averaged over Australia was 105°F (40.3°C), eclipsing the previous record of 104°F (40.2°C) set on 21 December 1972. Never before in 103 years of record keeping has a heat wave this intense, wide-spread, and long-lasting affected Australia. The nation's average high temperature exceeded 102°F (39°C) for five consecutive days January 2 - 6, 2013--the first time that has happened since record keeping began in 1910. Monday's temperatures extended that string by another day, to six. To put this remarkable streak in perspective, the previous record of four consecutive days with a national average high temperature in excess of 102°F (39°C) has occurred once only (1973), and only two other years have had three such days in a row--1972 and 2002 (thanks go to climate blogger Greg Laden for these stats.) Another brutally hot day is in store for Wednesday, as the high pressure region responsible for the heat wave, centered just south of the coast, will bring clear skies and a northerly flow of air over most of the country. A slight cool down will occur later in the week, as the high weakens and slides to the east of Australia. The western coast of Australia may see cloud cover and rain from Tropical Cyclone Narelle this weekend, but the rest of the country will see very little in the way of cloud cover or rain during the coming week.
Figure 1. Aerial view of fire at Copping/Forcett, Tasmania, at around 4pm on 4 Jan 2013, taken from an airplane leaving Hobart Airport. Image credit: Wikipedia.
As discussed by wunderground's weather historian Christopher C. Burt in his Monday post, Australia's extreme heat helped fuel wild fires in southeastern Tasmania that burned to the ground at least 100 homes last Friday and Saturday. The temperature peaked in the state capital of Hobart at 41.8°C (107.2°F) on Friday, the hottest temperature on record for the city, and tied for the 2nd hottest temperature ever recorded in Tasmania (records go back to 1882). The 2013 Australian heat wave extends a period of unusual warmth for the country. The last four months of 2012 were the hottest such period on record, with an average Australian maximum temperature +1.61°C, just beating the previous record of 1.60°C set in 2002. The current heat wave has not yet set a record for all-time hottest temperature in Australian history, which remains the 50.7°C (123.3°F) reading on 2 January 1960 at Oodnadatta, South Australia.
Figure 2. Departure of high temperature from average (using a base period of 1961 - 1990) for the first six days of 2013. A large area of Australia has had high temperatures more than 6°C (11°F) higher than average. Image credit: Australian Bureau of Meteorology.