Wednesday has potential to be one of the worst fire weather days South Australia has experienced in a few years with Fire Danger expected to reach Catastrophic in several districts.

Temperatures will peak in the low-to-mid forties coinciding with humidities dropping below 10 percent and northerly winds gusting in excess of 60km/h. This combination is expected to affect parts of West Coast, Lower Eyre Peninsula, Eastern Eyre Peninsula, North West Pastoral, Flinders, Yorke Peninsula, Mid North, Mt Lofty Ranges, Adelaide, Murraylands and North East Pastoral, raising fire danger to Extreme-to-Catastrophic. Blowing dust is likely to also be a problem. As usual, Eyre Peninsula will cop the worst of this.

In terms of how large an area is to be affected by Extreme-to-Catastrophic fire danger, this could turn out to be one of the most intense fire weather days the state has seen in a few years.

Hints of what is to come has been observed across inland Western Australia today, particularly in the Eucla and Goldfields. It was the hottest November day in more than 70 years at Forrest (45.5 degrees), more than 60 years at Laverton (44.7 degrees) and more than 20 years at Leinster (44.3 degrees). Fire danger reached Catastrophic in these areas as humidity dropped below five percent and hot winds gusted more than 50km/h.

A gusty but mainly dry cooler change will drop temperatures by as much as 15-to-20 degrees in southeastern WA later today and SA later tomorrow.