The country's alpine resorts face a nervous couple of weeks as unusually warm weather leaves their ski runs a verdant green with just a few patches of the white stuff.
The same warm spell that is setting heat records from Adelaide to Melbourne and Sydney is also keeping temperatures stubbornly above zero at the ski fields, rendering snowmaking all but useless.
"Any snowmaking would be fairly futile at the moment," said Brett Dutschke, senior meteorologist with Weatherzone.
With fewer than three weeks to go until the official Queens Birthday long weekend opening of the season, resort operators in NSW and Victoria are banking on a couple of cold fronts to bring fresh dumps or at least to allow the snow guns to fire up.
"We've got fingers crossed, hoping for the best for the opening weekend," said Richard Phillips, sales and marketing manager at Perisher. "We'll make [snow] at every available opportunity."
The Bureau of Meteorology is forecasting tops of 7-11 degrees for Perisher Valley over the next week with minimums remaining above zero until next Monday.
Mount Buller did get three to five centimetres of natural snow a few weeks ago during the cold snap to start May.
"Since then it has warmed up, and we haven't had any," said Niki Donaldson, a media and marketing officer at the resort.
It has also been too warm for snowmaking, which needs temperatures "at least below zero", with -2 degrees the best, she said.
Nor will the coming week offer much of a break.
"It's looking a bit wet and cool, but not cold enough," Ms Donaldson said.
However, the ski industry can take heart from the fact that a lack of snow by this point in autumn is little guide to how the season as a whole will fare.
"The relationship between pre-season [first half of May or earlier] snowfalls and the eventual peak seasonal depth is essentially non-existent," said Blair Trewin, a senior climatologist at the bureau.
"So mild conditions at this time of year don't really tell us anything about how the season will end up."
Both Sydney and Melbourne extended their records of late-autumn warmth on Monday.
Sydney's top of 26.1 degrees made it 10 consecutive days above 22 degrees, beating the run of six such days this late in the year set in 1974, Mr Dutschke said.
The updated forecasts suggest another week of 23-26 degree days ahead for Sydney, a run almost certain to beat the record for warmest week this late in May, Mr Dutschke said. The city's record May average of 22.7 degrees set in 1958 is also within range.
Melbourne's 23.5 maximum on Monday made it nine days above 20 degrees, beating the run of seven such days in 1907 and 1957. That run may end on Tuesday or Wednesday, with 20 and 19 forecast for those two days, the bureau said.
Adelaide beat its record hot day this late in autumn last Friday, while Hobart did the same a day earlier. Big blocking high-pressure systems are pushing cold fronts further south than usual.
Conditions should also remain mild in the Alps for some days yet.
"There'll be no snow in the coming week but there could be some in the middle of next week," Mr Dutschke said.
Weatherzone.com.au is owned by Fairfax Media, publisher of this website.