Canberra shivers through cold August night

A heavy frost has painted the town silver as Canberra experienced its coldest August night in two decades.

Drivers scraped their windshields and even backyard alpacas weren't immune, waking with a layer of ice crystals on their backs.

The temperature plunged to -7.6C around sunrise on Tuesday, the Bureau of Meteorology recorded.

That's the national capital's coldest night since July 29, 2011 and the biggest August freeze since 1994.

It was colder overnight on the plains of Canberra than at ski resort Thredbo.

The freeze is set to continue on Tuesday night, bureau senior meteorologist Sean Carson says.

"If we get to -6 degrees again tonight that will be our coldest run of nights, or the first time we've had four nights greater than -6 in a row since 1970," he told AAP.

The cold is related to the snowfall in Canberra on Friday.

The front that moved across the country had very cold air from Antarctica behind it, which was now hanging around over southeast Australia, Mr Carson said.

But the news isn't great for skiers: the cold nights have come with very clear skies, little wind and no cloud cover, so no snow is expected.