Bureau of Meteorology forecaster Helen Reid said the colder air will arrive on Saturday, and some areas will also see strong winds on Saturday night.
While Sydney’s temperatures won’t drop more than a couple of degrees, the wind chill factor will likely make the overnight minimums of 7 or 8 degrees feel more like 5 or 6. Residents of the Blue Mountains will really feel the cold as temperatures dip below zero.
“Sydney doesn’t get that cold, but if you’re in the Blue Mountains it will be particularly cold on Saturday,” Ms Reid said, while the Illawarra region is likely to bear the brunt of the damaging winds “because of the way [the westerly] rolls down off the mountain.”
Blizzards are likely to develop in alpine regions above 1500 metres on Thursday afternoon, possibly lowering to 1200 metres overnight, while, above 1900 metres, winds are expected to average 90km/h with peak gusts in excess of 120km/h.
Perisher reported 13cm of fresh snow overnight and was expecting more on Friday morning, while Thredbo ski operators were “stoked” by the 80cm snowfall forecast at its resort over the next few days.
The NSW National Parks and Wildlife Service recommends people postpone their travel across alpine back country until conditions improve, with the bureau warning of increased avalanche risk.
Meanwhile in the state’s north, fires flared in Port Macquarie on Thursday due to strong westerly winds and the NSW Rural Fire Service’s large air tanker made its first ever drop.
The SES has advised residents in affected areas – including Sydney, Newcastle, Gosford, Wollongong, Nowra, Goulburn, Yass, Wagga Wagga, Deniliquin, Griffith, Hay, Wentworth and Thredbo – to move vehicles under cover or away from trees and secure loose items while the warning is in place.
Ausgrid also warned of potential power outages, asking people to “take a few minutes now to prepare and secure loose outdoor items so they don’t blow away into powerlines and cause outages”.
In Sydney, winds are expected to ease somewhat on Saturday and Sunday to 25-35km/h, with a slight chance of showers.
While Sunday morning will be cold, the conditions shouldn’t affect The Sun Herald City2Surf – apart from the westerly winds potentially giving a boost to runners on Heartbreak Hill, Ms Reid said.
Later on Sunday, however, the swell is likely to pick up. “Once this low pressure system moves to the east of Tasmania, then behind that these southerly winds start generating swells that move up the coast,” she said.
Jenny Noyes is a journalist at the Sydney Morning Herald. She was previously a writer and editor at Daily Life.
Natassia is a journalist for The Sydney Morning Herald.