Severe thunderstorms and heavy rainfall are set to batter Australia's east and north while the west coast swelters through a heatwave.
Bureau of Meteorology senior meteorologist Dean Narramore said severe thunderstorm warnings were likely to be issued during the week.
"Rain and thunderstorms, some severe, are likely to impact much of northern and eastern Australia this week," he said.
It comes after a wet start to the week with 24 hour rainfall totals above 100mm on the NSW-Queensland border on November 20.
November 21 is expected to deliver "another widespread day of storms for Queensland, NSW and possibly through parts of Victoria".
"Again, severe thunderstorms with large hail, damaging winds and heavy rainfall are possible every day," he said.
But the storm and rain activity will be "hit and miss" across large parts of eastern Australia and likely to come in bursts, Mr Narramore said.
"We're likely to see widespread 25 to 50 mm across much of eastern Australia and also through parts of the Top End by [the weekend]," he said.
Meanwhile in the west, a severe heatwave warning is in place for Perth and along the coastline with temperatures expected to soar to 40 degrees on November 22.
Extreme fire danger conditions are forecast for a broad region of the west coast due to hot, dry and windy days across the week.
Weather warnings are issued by the Bureau at bom.gov.au/australia/warnings