About 470 properties in the Blue Mountains will remain without electricity overnight after a day of wild winds, rain and snow.
At its height, snowfalls of 15 centimetres and wind damage cut roads and rail access to the upper Blue Mountains for more than six hours.
The Bureau of Meteorology says snow falls have occurred right along the Great Dividing Range and as far north as Queensland's Granite Belt.
The wild weather also affected Sydney's metropolitan area, with Sydney Ferries suspending services between Manly and Circular Quay due to big swells.
Commuters were still able to take the fast ferry or replacement buses.
Parts of the NSW south coast were saturated with more than 300mm of rain, accompanied by eight-metre waves.
In the Blue Mountains, the State Emergency Service had to help ferry drivers to refuge from 300 cars stranded by the mountain road closures.
But the SES's Jennifer Finlay says most of the 550 calls for help came from further to the south.
"The Illawarra south coast got hit pretty hard with lots of trees down a bit of roof damage, fortunately nothing too severe," she said.
Endeavour Energy reconnected more than 2,000 properties to power on Friday afternoon, but hundreds of outlying properties between Mount Victoria and Medlow Bath and in the Megalong Valley will not get power back until Saturday.
With temperatures predicted to get down to 3 degrees Celsius overnight, the company has urged people in areas where the power is out to check on neighbours who live alone.
Blackheath resident Noelene Turner says she is staying in bed to keep warm.
"I've got a little gas stove, I've filled up a few thermoses and sent them to the older women and other women who live alone nearby so at least they can have a cup of tea. It really is quite a desperate situation," she said.
Phil Campbell from the SES says they have received over 300 calls for help.
"We've had calls for help that relate to trees and branches down, causing minor property damage," he said
Two 18-year-old bushwalkers have been rescued from the Snowy Mountains after they set off an emergency beacon in Kosciuszko National Park on Friday morning.
Four year 10 students and two teachers from Trinity Christian School in Canberra were also rescued by the SouthCare helicopter.
They were snowed in while on a three-day hike for their Duke of Edinburgh Award in Namadgi National Park, south of Canberra.
The bureau says the unseasonal weather has been caused by a low-pressure system which is expected to move north throughout Friday.
But bureau forecaster Ewen Mitchell says while the snowfall is unusual, it is not unheard of at this time of year.
"I don't think there's been hugely heavy falls. [It's been] fairly widespread," he said.
"It's certainly not record breaking in terms that it's happened before."
Snow has also fallen in Victoria, with a group of 11 students and three teachers from Mooroolbark Secondary College stranded near Licola in the state's east on Thursday night.
The group was hiking in snow storms yesterday when the students developed hypothermia.
Three students and two teachers were transported out this morning and the remaining are hiking out, with Ambulance Victoria expecting them to be on their way back to Melbourne on Friday afternoon.
In Queensland, the Granite Belt was also experiencing unusual spring weather.
Ballandean resident Apolonia Behan says it is a beautiful sight.
"If you can imagine rain but falling down a lot slower and seeing white flakes," she said.
"When they drop to the ground it all melts because the ground is wet from rain and also it's too warm for the snow to stay as it is ... but it's like a lovely curtain."
© ABC 2012
20:10 EST Melbourne Airport hadn't experienced a colder night since 1997, as the mercury plummeted to -0.4 degrees early this morning.