Not even a fortnight after enduring one of the most intense heatwaves on record, South Australia, southern New South Wales and Victoria are set to toast in another wave of extreme heat. It will get very hot very quickly from early next week, with much of the region seeing mid-to-high 30 degree heat on Monday. By Tuesday, large parts of SA, VIC and southern NSW will see the mercury reaching into the 40s, including Adelaide and possibly even parts of Melbourne. A day or two of relief is then likely, at least for coastal locations, as a gusty southerly change sweeps through. Melbourne is set to see just 24 degrees on Wednesday, while Adelaide can look forward to a slightly cooler 33 degrees. However, it will quickly heat up again from Thursday as an even more intense band of heat pushes in. By late in the working week or next weekend, most places will again be sweltering in temperatures pushing into the high 30s and 40s. For this event, light winds will thankfully limit fire danger for much of the time, although it will still be elevated due to the very hot temperatures. This coming Tuesday is likely to be the worst days for fires in the near future, as winds pick up ahead of and with the front. The cause of the continued spells of extreme heat is a persistent belt of high pressure over Australia which has been relentless this summer. This has brought extended periods of clear skies which in turn has allowed heat to continue to build over the continent. With little in the way of cold fronts or cloud, heat has been allowed to pool over the southern states, creating these extended spells of very hot weather. Until this pattern breaks down, Australia's south will continue to roast in the extreme temperatures. Current indications suggest the hot spell is unlikely to be snapped until at least the first week of February.