Fires threatened Sydney's outskirts on September 10. Photo: Nick Moir
The exceptionally warm start to spring for south-eastern Australia is likely to extend well into October, breaking more records and exacerbating early-season fire risks, according to Weatherzone.
Both Sydney and Melbourne – and much of the nation – are well on course to set record temperatures for September with weather models indicating next month will also be unusually hot, said Weatherzone meteorologist Ben McBurney.
“Our fortnightly models indicate it's going to be a very warm end to September, so it's very likely we're going to see the warmest September on record for Sydney at least,” Mr McBurney said.
Sydney's maximums this month are running at about 23.6 degrees, well above the long-term norm of 20 degrees, and eclipsing the previous record of 23.3 degrees in 1980. The Bureau of Meteorology predicts days will average about 24 degrees over the next week. Minimum temperatures are also well above previous records.
Melbourne's maximums are running at about 19.5 degrees, just shy of the 2006 record of 19.7 degrees, but the mercury is likely to reach an average of about 21 degrees or more for the next week. “There's a good chance they're also going to break their [September] record as well,” Mr McBurney said.
The Bureau of Meteorology said it was possible September would see more monthly records fall.
“The area of most-abnormal warmth has been inland central and eastern Australia,” said Blair Trewin, senior climatologist at the bureau. “A lot of that area has been 4-6 degrees above normal for September to date.”
Alice Springs is running at about 3 degrees above the previous record for September. "It's just been ridiculous," Mr McBurney said.
Australia's record heat over the past year has surprised climate experts, not least because it has occurred in a period without an El Nino weather pattern over the Pacific Ocean, the conditions that typically see national temperatures spike.
Outgoing chief climate commissioner Tim Flannery also highlighted the unusual heat and the early start to the fire season around Sydney on Thursday when he disclosed that the new Abbott government had axed the commission.
Dr Flannery said it remains important that the public continues to get “a reliable, apolitical source of facts” on climate change, a task he said was made harder by the commission's demise.
Weatherzone's Mr McBurney said weather models indicate the potential for more early-season fires remains high, particularly in NSW.
“September has been quite hot and our models suggest October will also be very hot,” Mr McBurney said. “The early part of the fire season could be quite bad.”
There could be more potentially bad fire days by the middle of next week, with temperatures likely to approach 30 degrees. “Those westerlies will come in and dry things out again,” he said.
There's also little sign of rain over the next fortnight for the Sydney region. Melbourne can expect close to average rainfall for September "but the further north you go, it's pretty dry", he said.
Melbourne has received about 44 millimetres of rain so far in September, a month that typically sees about 58 millimetres for the city. Sydney's rain tally of 35.8 millimetres is about half the long-run average of 68.6 millimetres.
As of Friday afternoon, the Rural Fire Service was reporting 19 active fires across NSW with just two of them uncontained.
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