Shade and sunscreen will be essentials as Christmas Day lunches around much of Australia are set to be hosted under hot and largely dry skies.
After a cold and wet December for many, the summer's first heatwave is forecast for southern Australia between Christmas Day and New Year.
Many towns and cities will experience classically Australian summer conditions, though one state capital is set for its coolest Christmas Day in years.
Victoria
After thunderstorms this week left some homes without power, Victorians can expect a calmer albeit hotter Christmas day. Melbourne will reach a top of 28 degrees Celsius on Sunday, while Mildura in the state's north-west will rise to a typically roasting 37C.
In the east of the state, Sale and Mallacoota will hit the high 20Cs, while Albury-Wodonga is expected to climb to 35C.
The popular Christmas holiday destination towns along the Great Ocean Road in the state's south-west will enjoy a fine Christmas day, with temperatures reaching 25C in Anglesea, 23C in Lorne and 22C in Apollo Bay.
Senior forecaster at the Bureau of Meteorology (BOM) Matthew Thomas said hotter days will follow at the start of next week, with temperatures exceeding 40C in some parts of Victoria.
He said a cold front will then move through the state on Wednesday bringing some relief and lower temperatures, with the possibility of showers and storms.
Boxing Day Test
The life and enduring legacy of cricket icon Shane Warne will be celebrated at this year's Boxing Day test with players from South Africa and Australia set to wear floppy hats in honour of the spin-king during national anthems.
Those same hats could come in handy in the field, as the MCG is set for a run of hot days, with forecasts of 29C, 34C and 35C on Days 1 to 3.
The chance of some rain-affected play increases slightly as the test progresses, with a 30 per cent chance of rain on Day 4 — which, on recent form, is roughly the same likelihood as the Test lasting that long.
Tasmania
Tasmania will unsurprisingly host some of the country's cooler Christmas lunches, with a maximum of 25C in Hobart and Launceston on Christmas Day, and colder still in Burnie and Devonport, where temperatures will be in the low 20Cs.
A cooler Boxing Day will give way to a stretch of warmer days across the state, with Wednesday forecast to reach 31C in Hobart.
New South Wales and ACT
Most of NSW will be dry on Christmas Day, but there is a chance of a brief storm in the outer west of Sydney at some point in the afternoon. Otherwise, Sydney will reach a maximum of 28C, as will Newcastle.
There is a small chance of Christmas Day rain in Port Macquarie where it will reach 28C, but a higher 70 per cent chance of rain and thunderstorms is present for Byron Bay and the northern rivers area, with temperatures in the mid to high 20Cs.
Daytime temperatures will reach around 30C along the South Coast.
Light winds will move through Canberra on a warm and partly cloudy day, with the nation's capital reaching an expected top of 31C.
It will be hot and sunny Christmas Day further west, with a top of 35C in Wagga Wagga and Broken Hill, and a similarly warm 33C in Dubbo.
The state will continue to heat up on Boxing Day and throughout most of the week.
Sydney to Hobart Yacht Race
As crews in the Sydney to Hobart Yacht Race approach the start line on Boxing Day Monday, they should be met with generally fine conditions under sunny skies, with a light east to north-easterly wind.
Those conditions could change as boats travel along the New South Wales coast, according to the BOM's senior NSW meteorologist, Gabrielle Woodhouse.
"It will be a reasonably decent start to the race. For the big boats that tend to take a much quicker path down to Hobart, they will be in the northerly winds and they will probably get in a lot earlier than the smaller boats," Ms Woodhouse said.
"When you're out on the water for those extra days, that's when you start to encounter these other systems.
"For the boats that take a little bit longer, we are looking at the passage of a trough, at this stage probably sometime on Wednesday or Thursday. That could bring a south to south-easterly change as it moves through."
The race forecast will continue to be refined up to and during the race.
BOM will conduct updated briefings to race teams today and again on Boxing Day as forecasts are narrowed.
South Australia
South Australia is set for a string of bracingly hot days, with maximums exceeding 40C in the days following Christmas.
Adelaide will reach a top of 31C on Sunday, 37C on Boxing Day and 41C on Tuesday.
The A-League match between Adelaide United and Wellington Phoenix scheduled for Tuesday has already been called off because of the forecasted heat.
Closer to the Victorian border, Mount Gambier will have a Christmas Day top of 26C before several days in the mid to high 30Cs.
Kangaroo Island will enjoy a Christmas Day in the mid 20s, while quaint costal town Robe will be cooler still with a mostly sunny 21C.
The festive season in Coober Pedy will be typically sweltering — a 39C Christmas Day is set to be followed by consecutive days in the 40Cs.
South Australia can expect some slight relief later in the week, with cooler southerly winds predicted around December 29th.
Western Australia
Perth is set for its coolest Christmas Day in years, with a comparatively chilly forecasted top of 31C, some 11C cooler than last year's scorching 42.8C maximum.
BOM forecaster Jessica Lingard said a trough will bring cooler conditions down the west coast.
"This year is looking beautiful and significantly cooler than the Christmases we've experienced in the last few years," she said.
It augurs a run of pleasant warm days in Perth, with a Boxing Day top of 27C followed by temperatures in the mid to high 20s.
Coastal holiday hotspots will enjoy near-ideal Christmas lunch weather, with tops of 24C in Esperance, 22C in Albany and 25C in Margaret River.
Further north, there is a hot and potentially wet day in store for Broome, with the possibility of showers and a thunderstorm amid a maximum of 34C.
Northern Territory
Tropical Cyclone Ellie has been downgraded, but there are still risks of heavy falls and damaging wind gusts across northern parts of the country. Authorities are warning that parts of the Northern Territory could flood in the coming days.
The Bureau of Meteorology expects as much as 200-300mm of rain in the Tanami region, with Chief Minister Natasha Fyles yesterday urging people to reconsider travel.
Showers and storms will be a feature of the Christmas period for much of the NT.
Darwin will continue to experience falls throughout the week, with a Christmas Day top of 32C punctuated by rain — with a chance of up to 20mm and a possibility of thunderstorms.
In Alice Springs, Sunday's top of 28C will likely bring with it a small amount of rainfall, with temperatures in the low 30s for the rest of the week.
Queensland
Late morning and early afternoon showers could be a part of many Queensland Christmases, with low rain totals expected across parts of the state.
Brisbane will reach a max of 29C on both Christmas and Boxing Day, with senior forecaster at the BOM Harry Clark describing the forecast for Sunday as a bit of a "mixed bag."
"The good news is it's not going to be too warm. There's a little bit of humidity around but nothing unusual for this time of year," he said.
"Once you look into next week, it's a very similar forecast."
It will be rainy and 28C on the Gold Coast, similar in Townsville with a rainy 29C, while Cairns, Longreach and Mount Isa will all reach low 30Cs on Christmas Day.
