You may need to get your brollies out on Christmas Day. Photo: Brook MitchellPlanning outside festivities on Christmas Day? Better pack an umbrella along with the turkey or ham if you’re in Sydney – or anywhere else in the country’s south-east.
Similar advice holds for Friday and Saturday too, as showers and possible storms threaten to soak more than a few parties.
The Harbour City is among the centres facing possible showers and the odd storm in a band taking in NSW, Victoria, the ACT and Tasmania, Weatherzone forecasters say.
“There’s likely to be a low pressure trough nearby or there is even a small chance of a low pressure system sitting in the Tasman Sea,” Rob Sharpe, a meteorologist at Weatherzone, said. “So that means there’s the chance of showers on Christmas Day in Sydney”.
The chance of showers is more likely in the city’s east, but could also affect the rest of Sydney.
Sydneysiders shouldn’t let their spirits sag just yet though, with Mr Sharpe adding, “It’s not that there’s likely to be showers in Sydney, but there’s a chance.”
Christmas Day should also be “a nice warm day”, with temperatures expected to range between 18 and 27 degrees.
That outlook looks to be close to Sydney’s long-term average for December, which ranges from a minimum of 17.5 degrees to a maximum of 25.2 degrees.
A Bureau of Meteorology spokesperson noted the speculation over the holiday weather, but said the agency won’t be releasing a forecast until a week before Christmas in line with their standard practice. Soggy days
Friday’s soaking across the city is not likely to let up, with the possibility of thunderstorms from around 5 pm onwards for Sydney.
The potential for storms lasts “right through the evening and even the early hours of Saturday”, Graeme Brittain, a meteorologist with Weatherzone, said.
The absence of a sea breeze means any storms could track across the city and reach the coast, he said.
The chance of a storm now appears higher on Friday than on Saturday.
Still, there could be showers through the day, with any storms most likely between mid-afternoon to the early evening, Mr Brittain said.
Such weather should favour indoor activities, with shopping among them.
Over the years, Christmas Day itself has featured more for extreme cold than heat or rainfall, bureau data show.
For instance, for daily extremes, Mt Buller in Victoria holds the record for the lowest maximum for any December day in Australia.
In 2006, the mountain’s mercury climbed no higher than minus-0.8 degrees, with the state’s Mt Baw Baw’s minus-0.4 degree reading notched second place that year’s Christmas Day.
Christmas Eve, though, boasts the highest December maximum for any site in Australia, with a roasty 49.5 degrees clocked at Birdsville Police Station in 1972.
Last Christmas Day in Sydney was dry with a maximum of 25 degrees for those who can’t remember. Beyond Christmas
People looking to recover from this year’s Christmas excesses with a trip to the beach might be in for some luck.
Mr Sharpe said while there’s a lingering chance of showers in the days following Christmas, a spike in temperatures is also expected as the year nears its demise.
“What’s probably more notable is we’re likely to see temperatures increase later on in the week,” he said. “We could see some hot weather in the lead-up to New Year’s.”
According to the Canadian meteorological service, south-eastern Australia can expect above-average temperatures for the week starting December 23, while most of the rest of the country should be close to average. (See chart below.)
As a guide for those travelling overseas for that week, the north-east of US should have recovered from the current deep chill from an Arctic polar vortex bursting southwards, and can expect warmer-than-usual conditions.
London, too, might be on the fringe of milder-than-normal weather for the week of December 23-30, although continental Europe may be on the relatively chilly side compared with long-run temperatures. Hot and dry January
Further into the holiday season, eastern Australia looks likely to be on the warm side.
The latest three-month outlook from the Bureau of Meteorology points to a continuation of the hotter-than-average conditions, particularly for NSW and Queensland. (See chart below showing the chance that maximum temperatures will exceed the long-term average in January alone.)
The bureau attributes the near-term warming trend to conditions in the Antarctic that favour higher-than-usual pressure systems over Australia.
The other main influences on Australia’s climate – from the Pacific and Indian oceans – remain in neutral modes.
Along with the warmer-than-normal temperatures, the odds strongly favour below-average rainfall across eastern Australia in January. (See below for bureau chart on the chance of exceeding median rainfall.)
The combination of relatively warm and dry conditions is likely to extend through the first three months of 2017, increasing bushfire risks.
Australia posted its second-wettest winter on record this year, before a turn in the weather prompted authorities to extend the range of Australia expecting a busier-than-normal bushfire season.
Weatherzone is owned by Fairfax Media, publisher of this website.
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This story Administrator ready to work first appeared on Nanjing Night Net.