Total fire bans are in place for parts of South Australia and Victoria today as temperatures soar ahead of an approaching cool change. In South Australia, temperatures are expected to reach 39 degrees in Adelaide today and 44 at Leigh Creek and Roxby Downs. These maximums are 8-10 degrees above average for this time of year. Adelaide had already reached 34 degrees at 10:20am. Across the border, tops of 42-43 degrees are expected at Swan Hill, Ouyen and Mildura in northwest Victoria. Melbourne was previously expected to reach the high thirties, although a southerly now looks like arriving earlier than expected and could limit heating to about 35-36 degrees in the city. This would make it Melbourne's third day over 35 this month and the sixth so far this season, which is close to what's expected by this point in January. Today's heat will combine with fresh and dry winds in some areas, causing very high to severe fire danger ratings across both states. Total fire bans are in place for nine of South Australia's 13 districts and in the Mallee, Wimmera and North Central Districts of Victoria. A southerly change will sweep over the southern districts of South Australia and Victoria from this afternoon, before pushing further inland tonight. The wind change itself may be problematic for any active fires, although cooler temperatures will alleviate fire danger in most areas by tomorrow. On Wednesday, most of Victoria and southern parts of South Australia will be 10-15 degrees cooler than today. Adelaide could go from near 40 degrees today to a top of 28 tomorrow afternoon. Melbourne is forecast to reach just 21 degrees on Wednesday after a wet and cloudy morning.