Scorching heat and high winds trigger extreme fire danger warnings

Millions of people are on alert for high to extreme fire danger today as hot and windy conditions sweep through south-eastern Australia.

Fire authorities in South Australia are warning the brunt of the danger will impact the west coast, Yorke Peninsula and the Mount Lofty Ranges where there is extreme fire danger today.

There are concerns homes may have been lost at the Fleurieu Peninsula in the Mount Lofty Ranges, where hundreds of firefighters are battling to contain a blaze.

READ MORE: Fears homes may have been lost as bushfires rage in South Australia

The Country Fire Service (CFS) this morning issued a watch and act warning for residents at Deep Creek, Silverton, Blowhole Beach Road and Delamere, urging them to prepare to leave.

Bureau of Meteorology meteorologist Christie Johnson says other parts of SA will have temperatures above 30 degrees, and possibly up to 40 degrees, raising the fire danger.

"We also have some of these high fire danger areas that are very close to the threshold for extreme fire danger and that includes regions such as the Murraylands and the upper south-east," she said.

Victorian firefighters are also bracing for extreme fire danger across large parts of the state over the coming hours.

The Country Fire Authority (CFA) has declared a total fire ban for the North Central, Central and Wimmera fire districts, where temperatures up to 35 degrees are expected.

READ MORE: Flood warnings across multiple states amid new cyclone fears

"Conditions will make it difficult for firefighters to suppress a fire should one start," said CFA chief officer Jason Heffernan.

The bureau is also forecasting a chance of some thunderstorms, particularly through West and South Gippsland, with the potential for new fires starting from lightning.

Authorities in Tasmania expect a high fire danger across the state today, except for the north-west region.

But modelling by the Bureau of Meteorology suggests conditions could deteriorate.

"We're now expecting high fire danger right across the state, reaching extreme fire danger through the east coast and the Midlands district," said Johnson.

The hot and windy conditions today extend to Western Australia, where an extreme fire danger warning has been issued for some inland parts of Perth.

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