Christmas Day will be hot, dry and sunny in southern Australia, but ex-tropical Cyclone Ellie is spreading rain and storms across the northern end of the country.
A severe weather warning is in place for intense rainfall and damaging winds over the central Northern Territory.
In the Barkly region, the Bureau of Meteorology is warning of wind gusts over 90km/h and up to 380mm of rainfall within 24 hours in some areas.
The Gregory, Carpentaria and Tanami weather districts are likely to get 24-hourly rainfall totals between 140 to 200mm, with isolated totals up to 250mm.
“Ex-Tropical Cyclone Ellie is currently west of Tennant Creek and is forecast to track very slowly south to southeast today,” BOM’s alert issued just after 3am on Sunday stated.
“The low is already producing very heavy to intense rainfall, and may strengthen a little further during Sunday and Monday.”
The capital city, Darwin, could get up to 15mm of rain on Christmas Day with a maximum temperature of 33C.
Southern scorcher
Christmas and Boxing Day will be “scorching hot” over southern Australia.
It comes after a slow start to summer, in terms of warm temperatures, with Victoria even experiencing its coldest summer temperature on record last week.
“South Australia just gets hotter and hotter,” Sky Weather meteorologist Alison Osborne said.
“On Sunday, Christmas Day, temperatures will climb into the high 30s and then everything spreads towards the southeast. It’s going to be a toasty start to the Boxing Day Test.”
Adelaide is forecast to reach 32C on Christmas Day and Melbourne is looking at 30C.
“Now by the time we reach Monday into Tuesday, Melbourne and other parts of regional Victoria could be sweltering in the hottest temperatures since January,” Ms Osborne said.
Melbourne is forecast to reach 31C on Boxing Day and 37C on Tuesday.
“Meanwhile, from Tuesday into Wednesday, a severe heatwave becomes established over South Australia,” she continued.
“This will see temperatures nudging the 40 degree mark, in some cases for the first time in two years.
“This does increase one’s risk of heat-related injury and stress and overnight temperatures will be significantly above average too meaning little chance for your body to recover.
“Heatwave warnings are likely to remain in place until at least Thursday when another cool change comes effectively flushing out the heat.”
Adelaide is expected to reach 37C on Boxing Day, before climbing to 40C on Tuesday.
Like Adelaide and Melbourne, there is also no rain forecast in Hobart for Christmas. Christmas Day will likely reach 25C and then 23C on Boxing Day. It could breach 30C midweek however.
Across the other side of the country in Perth, Christmas Day will also be a dry one with a top of 30C. The maximum temperature will drop slightly to 27C on Boxing Day before heating up again midweek.
Canberra is also expecting no rain and a hot, sunny 31C for Christmas Day and then 32C for Boxing Day.
A heatwave is categorised as hotter than average temperatures for more than three days in a row.
BOM’s official three-day heatwave forecast for Sunday, Monday and Tuesday shows a low-intensity to severe heatwave stretching across five states: Western Australia, South Australia, Victoria, Tasmania and NSW.
“Severe to low intensity heatwave extends from the southwest Pilbara and far northern Gascoyne in WA over most of southeast WA, most of SA, most of Victoria, most of Tasmania, and parts of southern NSW,” BOM’s heatwave service warns.
Sydney has escaped the heatwave but will still be a warm 28C on Christmas Day and 29C on Boxing Day.
Queensland storms
It won’t just be a stormy Christmas for the Northern Territory.
Storms could develop on Sunday in southeast Queensland and the northern half of the NSW ranges, Ms Osborne said.
In the capital, Brisbane is looking at showers and a top of 29C.
But further north in Townsville, up to 70mm of rain is expected on a very damp Christmas Day. The mercury will peak around the 30C mark.
Mackay could also see up to 70mm of falls, with a high of 28C.