An impending burst of hot, dry and windy weather has prompted a total fire ban in parts of South Australia and Tasmania on Thursday.

Northerly winds strengthening ahead of an approaching cold front will drag hot and dry air across parts of southern and southeastern Australia during Thursday and Friday.

Image: Forecast surface temperature on Thursday, showing hot air being carried towards southern Australia ahead of an approaching cold front.

Temperatures are forecast to reach 10-15 degrees above average in parts of South Australia, Tasmania, Victoria and southern NSW on both days. 

On Thursday, Adelaide and Melbourne are both tipped to reach the mid-thirties. Hobart's forecast tops of 30 and 31 degrees on Thursday and Friday would be the city's warmest pair of days on record this early in spring.

The combination of this heat with dry and gusty wind is likely to cause Very High to Severe fire danger ratings in parts of all four states during the next two days, possibly reaching the Extreme category in some areas. 

Total fire bans have been declared in parts of Tasmania and South Australia during Thursday, with further fire bans possible for Friday.

Cooler air will spread over southern Australia on the weekend, helping alleviate fire danger ratings in South Australia, Tasmania, Victoria and southern NSW.