Early-summer heat to challenge records this week
Severe heatwave conditions will affect five states and territories this week, challenging December records and elevating fire danger ratings.
A large mass of hot air built up over Australia in recent weeks thanks to an absence of widespread cloud and rain. While this buildup of heat is a typical occurrence at the beginning of summer, some places are experiencing record-breaking temperatures for this early in the season.
Last week, Perth registered its earliest four-day spell of days over 37 degrees in 120 years of records. This hot spell occurred 10 days earlier than the previous record, which took place from December 13th to 16th in 2013.
On Saturday, the NT's Victoria River Downs (44.7C) and Queensland's Gatton (42.6C) registered their hottest December day on record. Both locations have observations dating back to 1965.
This week, the large mass of hot air will target western, northern and eastern parts of Australia.
Severe heatwave conditions are forecast to affect parts of NSW, the ACT, Queensland, the NT and WA between Monday and Friday.
In southeastern Australia, temperatures will spike during the first half of the week ahead of a cold front.
Image: Forecast surface temperature on Monday, December 9th.
Victoria and Tasmania will see the peak of this heat on Monday. Temperatures are likely to climb 10-15 degrees above the December average in parts of Victoria, causing Very High to Extreme fire danger ratings across the state. Parts of Tasmania should also see Very High ratings on Monday. Cooler air will spread over both states by Tuesday in the wake of the cold front.
This week's heat will be longer-lasting for parts of NSW, the ACT and Queensland. Canberra should exceed 30 degrees between Monday and Thursday and could near 40 degrees on Tuesday. Large areas of inland NSW will reach the mid to high thirties between Monday and Thursday, with some places likely to push into the forties. Even western Sydney is tipped to reach 42 degrees on Tuesday.
Image: Forecast surface temperature on Tuesday, December 10th.
Across the border, a severe heatwave will also affect parts of southwest Queensland between Monday and Thursday, with temperatures forecast to reach 43-45 degrees on multiple days in some places.
This week's heat will cause Very High to Severe fire danger ratings in parts of NSW and Queensland. Unfortunately, this burst of heat will affect parts of both states that have been ravaged by fires in recent weeks. On Monday morning, there were close to 90 fires actively burning across NSW.
Image: Forecast surface temperature on Wednesday, December 11th.
Sweltering heat will also affect much of the NT and WA this week. Darwin is forecast to reach 35-36 degrees every day between Monday and Sunday, which is well above its December average maximum temperature of 33 degrees. With six days already exceeding 35 degrees this month, the upcoming heat should challenge Darwin Airport's record for the number of days at or above 35 degrees during December, which is nine (from 2002).
In WA, hot air will gradually spread from the state's north towards the southwest as the week unfolds. Perth is forecast to see daytime temperatures returning to the high thirties or low forties between Wednesday and Sunday. With four days above 37 degree already in the bag this month, and another five forecast this week, Perth could challenge its December record of eight days at or above 37 degrees, which occurred in 2012. Observations for Perth date back to 1897.
Image: Forecast surface temperature on Thursday, December 12th.
Heatwaves are a dangerous phenomenon and have caused more deaths in Australia than any other natural hazard. You can find information about coping with heatwaves from a doctor or by visiting your state or territory's public health website.