Firefighting aircraft crashes, crews battle bushfire as temperatures soar in Victoria

A small fire-fighting aircraft has crashed in Victoria's north-west amid soaring temperatures across the state.

The single-engine air tanker crashed at the Linga airbase, about 60 kilometres west of the small farming town of Ouyen, just before 5:30pm. 

According to a State Control Centre spokesperson, the plane was providing support for a fire at Patchewollock.

"The aircraft was on fire as a result of the accident and has since been extinguished," the spokesperson said.

"The pilot has safely evacuated the aircraft and is being attended to by emergency services.

"The incident will be subject to an investigation."

A watch-and-act warning is in place for Patchewollock, with fire crews battling a grass fire on Baring South Rd. 

The incident came as temperatures across western and northern parts of Victoria reached the mid to high 30s this afternoon.

Hopetoun Airport in the Mallee hit 38.8 degrees about 3:45pm, with warm, gusting winds up to 61km/h. 

Nearby Swan Hill hit 37.8C, while Charlton reached 37.2C and Mildura hit 38C. 

The weather bureau said temperatures in Melbourne would reach 33C, which is 9–10C above average, while across the state temperatures would be 6–10C above the December average.

It is a vast difference from Monday, when Victoria endured its coldest summer day in nearly 30 years and snow blanketed the state's alpine regions.

Emergency services have been called to numerous bushfires across the state, including at Markwood, near Wangaratta, Raywood and Myola near Bendigo and Rosebud on the Mornington Peninsula.

Stay up to date with the latest emergency information via VicEmergency and ABC Emergency. 

Senior meteorologist Dean Narramore said the cold front that moved through the state on Sunday and Monday had now moved into the Tasman Sea.

"What that means is those southerly winds have now turned northerly, so all that heat that sits across northern and central parts of the country is now moving down into south-eastern parts of the country," Mr Narramore said.

"That's why we're seeing temperatures spike [today] and Friday, with most of the state seeing temperatures around 5 to 10 degrees above average on Thursday and then on Friday across northern Victoria.

The BOM said the highest temperatures would be felt by those in the Mallee, with the mercury forecasted to reach 39C —and potentially into the 40s in the small farming town of Ouyen, which is predicted to be the hottest place in Victoria.

A total fire ban has been declared for the Mallee, Wimmera and Northern Country districts until the 11:59pm today.

An extreme fire danger warning is also in place for three districts — the first extreme warning for this season.

CFA assistant chief fire officer Gavin Wright said residents in western and northern Victorian needed to be "very alert".

"If a fire starts, it will spread very rapidly and be quiet fast-moving," Mr Wright said.

"They need to be doing all their preparation now, so whether that be around their home or their farm, it's about making those preparations; both physical preparation but also mentally, and communicating with your family and workers and the like about the risk."

He urged extra caution for grain farmers, who were busy harvesting across the region.

"I know some of them are probably feeling a little bit under pressure given that … ironically, some of the moist weather we've had over the last couple of days probably slowed down the harvest a little bit," Mr Wright said.

"We want to just be careful that they're not rushing things and that they are taking all the precautions, stopping when they need to, blowing the machine down, making sure they've got their firefighting equipment following them around where they're working.

"When the wind conditions and the weather is unfavourable, shut down for a period of time, go and find some other work that they can be doing on the farm and then return to harvest when conditions are more favourable.

"If the fire starts out in cropping areas, it will be very difficult to stop."

Water providers have warned residents to have an independent water supply to protect their propert.

Caution in the water

Mildura Life Saving Club captain Daniel Rosendahl urged precaution to anyone heading to local waterways to escape the heat.

"If you don't know the river, you know you need to have that level of respect for it," Mr Rosndahl said.

"If you don't know where to swim, come down and see us on the weekend.

"If you want to know where some of the hazards are, we can point those out.

"We do scan the river, we do check for those sorts of things — that's why we put the flags where they are because we know where they hazards are."