Parched regions in south-eastern Australia may finally get some welcome rain this long weekend as a icy blast brings days of stormy weather.

“Rain, and plenty of it,” is headed for Adelaide, Melbourne and Hobart, forecaster Weatherzone said.

Elsewhere, however, “the coldest day of the year” is coming.

All three state capitals have been short of rain so far this year, with farmers across the southern states battling a record drought that has taken some to the brink of disaster.

Millions of Australians (except those in Queensland and Western Australia) will get an extra day off for the King’s Birthday on Monday. They’ll also be rugging up “as an icy blast brings a mix of rain, hail, thunderstorms, blustery winds and snow”, Weatherzone said on Friday.

“A complex low-pressure system will drive a large pool of polar air over south-eastern Australia on Friday and Saturday and hold it there throughout the whole long weekend,” it said.

This system will spread rain and hail over large areas of South Australia, Tasmania, Victoria, NSW and the ACT over the long weekend. This will include wet weather in Melbourne, Adelaide, Canberra and Hobart.

“While this rain will not be welcome everywhere, it will be appreciated in the drought-affected areas of SA and Victoria.”

Bureau of Meteorology senior meteorologist Jonathan How said many people across NSW and Victoria would feel the wind chill from Saturday as two cold fronts pushed across the region.

“For many people Sunday will be the coldest day of the year,” How said.

The weather bureau has issued numerous warnings for the southern states, including a hazardous surf warning for the Byron, Coffs and Macquarie coasts in NSW.

With the ski season officially kicking off on Friday and up to 70 centimetres of snow forecast in some alpine regions, holiday-makers have been warned to take extra care on the roads.

“Tragically, so far this year up to midnight on Wednesday, 156 people have died on NSW roads, 14 more than this time last year,” Transport for NSW executive director operations management Craig Moran said.

“Anyone getting behind the wheel this long weekend should allow extra travel time due to the extra cars on the road. Don’t rush, be patient with other drivers and stay safe.

“We’re expecting morning frost and fog to be about, so slow down and drive to the conditions.

“If you’re heading to the snow, the roads can be slippery so you should also be prepared to fit snow chains to your vehicle when signage indicates or where directed at chain bays.”

Moran warned drivers to be particularly cautious when travelling through areas of NSW that were affected by recent floods.

“Some major roads around the Hunter, Mid-North Coast and North Coast were badly damaged during the recent floods, including the Oxley Highway, which remains closed west of Mount Seaview, due to a landslide,” he said.

“In addition, a lot of roads managed by councils were badly affected by the floods and some still have water on them.

“If you are driving in areas affected by flooding it is critical you drive to the conditions and never enter floodwaters.”

Transport for NSW warns of heavy traffic and delays expected around Sydney on Friday afternoon and again on Monday – including along the Great Western Highway between Glenbrook and Hartley.

Other pinch points are expected on Friday at Tugun, Hexham, the M1 at Wahroonga and Princes Highway at Milton and Ulladulla; while on Monday returning traffic to Sydney is expected to be busy at Hexham, the M1 at Wahroonga, Princes Highway at Ulladulla and Pheasants Nest.