September's average temperature for Sydney beats 33-year-old record - NEWS.com.au

Severe fire conditions are forecast for large swathes of NSW, with 17 bushfires burning out-of-control.

AT the risk of sounding like a broken record, how about this heat?

With a couple of days still to go, September has been smashing records as the state bathes in an early taste of spring.

Sydney's monthly average is on track to be 24.4C, beating the 23.3C record set in 1980 by more than a degree.

Leo Kennedy taken at Bingara, NSW. Picture: Sky News Weather Calendar 2014 Source: Supplied

To put that in perspective, the usual September average is 20C, while the average for the first month of summer is barely higher at 25C.

Record September warmth has been felt across most of NSW and other parts of Australia, including Canberra, Melbourne, Adelaide and Alice Springs.

Part of it is due to back-to-back days of clear, blue skies. Weather Channel senior meteorologist

Phillip Jones taken at New Norfolk, TAS. Picture: Sky News Weather Calendar 2014 Source: Supplied

Tom Saunders said Sydney had 36mm of rain this month — about half the average — and most of that fell in a single downpour on the 16th.

"When you've got 150 years of data and you break a record it's usually by 0.1C or 0.2C, but this is breaking a record by more than one degree, which is unprecedented," he said.

"There has been a lack of cloud cover over the past couple of months and that has allowed heat to build up in that part of the country, so whenever we get northerly winds, that hot air is drawn south.

"Secondly, we haven't seen cold fronts penetrating through the southern inland.

"The third factor, and this is probably the main one, is that the sea surface temperatures surrounding Australia are warmer than normal and they have been going back to last summer."

Grant Rolph taken at Cecil Plains, QLD. Picture: Sky News Weather Calendar 2014 Source: Supplied

Australia's temperatures are more heavily influenced than most other countries because we're surrounded by water.

All winds, except those coming straight from the interior, draw heat from the ocean, so warmer sea temperatures mean warmer days and nights.

Bureau of Meteorology NSW climate services manager Aaron Coutts-Smith said the next three months would continue the trend, with above average maximum and minimum temperatures predicted until early 2014 at least.

"We haven't really seen the cold fronts and instead there has been a dominance of westerly and north-westerly winds," he said.

Weather extremes such as those likely to be felt this summer provided inspiration for many of the photos included in this year's Weather Channel calendar, which showcases spectacular weather events across Australia. The calendar goes on sale on Wednesday.

Brett Michal Bayliss Sunset at Watkins Jetty Boatshed (In flood) (Long Jetty, The Entrance, NSW). Picture: Sky News Weather Calendar 2014 Source: Supplied