Severe fire danger warning on day expected to reach 39 degrees in parts of South Australia

South Australia's unseasonably early hot spell will get worse before it gets better for some parts of the state, forecasters predict. 

South Australia is already sweltering through an early burst of hot weather but it could get worse before it gets better for some parts of the state. 

The unseasonably early scorcher was tipped to reach 39 degrees in Adelaide today, with 37 forecast for Friday after an overnight low of 26. 

But towns in the state's north could see the summer's first 40+ degree days tomorrow, with Port Augusta expecting a top of 42 on Friday, with 41 predicted for Roxby Downs. 

Just after 1.30pm today, the Country Fire Service issued a watch and act warning for the Two Wells and Port Gawler areas, saying an out of control fire near Horseshoe Crescent and Buckland Park Road may threaten safety. 

It is one of several grass and stubble fires burning around the state. 

A total fire ban until midnight Thursday is in place for the West Coast, Lower Eyre Peninsula and Yorke Peninsula as well as the Mount Lofty Ranges and Kangaroo Island.

Sky Weather meteorologist Tom Saunders said the hot spell was unusual for this time of year. 

“We are expecting the hottest weather since last summer with temperatures about 15C above average for some parts, a heatwave across the Murray basin with heat lingering and severe fire dangers," he said.

“It’s only the first week of summer but summer scorcher is developing.”

The Country Fire Service has warned “very hazardous fire weather conditions” have been predicted.

By 8.40am it had reached 31.3C in Adelaide (West Tce) and it reached 35.3C as the cricket started at 10.30am.

"If you're heading to the cricket, you'll certainly want to drink plenty of water and take a hat and some sunscreen," Bureau of Meteorology senior forecaster Vince Rowlands said.

🌡️☀️ Just reached 30 degrees in Adelaide (West Tce) at 8:21 am. Mostly sunny with a forecast maximum of 39 today. Very hot throughout South Australia. Latest observations at https://t.co/KgGlltZQei

— Bureau of Meteorology, South Australia (@BOM_SA) December 5, 2018

The sweltering conditions will spread right across the state, with the Nullarbor expected to reach 42C and Roxby Downs, Woomera and Tarcoola all set for 41C.

The heat will continue on Friday before a cool change will sweep across the state from Western Australia, bringing temperatures down into the high 20s. The change is expected to hit late on Friday afternoon, says Mr Rowlands.

"We'll probably see some subtle wind changes during the day but the real heat isn't really going to be pushed out until late afternoon or early evening."

Adelaide reached a high of 35.6C at 3.30pm on Wednesday and dropped only to 23.9C overnight.

Just before 2am on Thursday, a 19-year-old man was arrested allegedly lighting three small grass fires in Christie Downs.

He has been charged with arson, while police are urging members of the public to be "vigilant" with hot weather today.

Specialised police patrols will be targeting bushfire-prone areas in the state today as part of Operation Nomad.

On Wednesday morning, a large haystack fire destroyed a shed in Long Plains and smoke is expected to be visible for at least another day.

Originally published as Severe fire danger warning on day expected to reach 39 degrees in parts of South Australia

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