Australia is experiencing dramatic weather contrasts across the continent, with low pressure troughs producing heavy rainfall in north eastern Australia and warm winds pushed ahead of another trough fuelling heatwaves and fire weather warnings in southern Australia.

Scorching conditions have been created in South Australia, Victoria and Tasmania as very warm northerly winds surge ahead of an approaching low-pressure trough tracking eastwards to the south-east of the country.

The Weather Channel has described the conditions in the three states as “the biggest fire situation seen so far this summer.”

Fire weather warnings were issued in South Australia, Victoria and Tasmania this afternoon. Most areas have been placed under a total fire ban, with temperatures in the high 30s expected.

In addition to the high temperatures, low humidity and strong winds are expected to further heighten the fire danger in the region.

People living within the warning areas have been urged to make the necessary preparations after consulting their bush fire survival plan. 

“Tomorrow is a big day across these states,” Dick Whitaker, chief meteorologist of the Weather Channel, said yesterday afternoon.

“We think a cool change will move through during Tuesday and Wednesday from the west and that will help bring the temperatures down and moderate fire dangers in the region."

While the south swelters, the drenching that occurred over parts of eastern Queensland and NSW in recent days likely to continue through to Thursday.

An upper-level trough and low-pressure trough coupled with a very moist airstream has been response for intense shower activity over the Sydney region, according to Felim Hanniffy, meteorologist at The Weather Channel.

Brisbane’s rains were due to similar conditions as well as a low-pressure trough developing off the coast which is feeding in a very moist airstream resulting in very heavy rainfall to coastal areas.

“Four-day ahead totals from today until Thursday show the rainfall bulls eye with falls of 100mm plus to be located over south-east Queensland and then from Friday to Monday over the New South Wales north and central coasts,” Mr Whitaker said.