Strong winds hit across the weekend making official temperatures look deceiving for the Southern Highlands and Tablelands according to the Bureau of Meteorology.
The strong winds will, however, ease on Monday as a high pressure system moves in and thaws the coast.
The Bureau's Helen Kirkup said the cold air mass moved over NSW across the weekend with the "air trajectory coming from Southern Ocean", bringing chilling overnight temperatures and a sprinkling of snow to the Snowy Mountains region.
"Sunday morning particularly ... we had some close to May records in terms of night time temperatures - we were down to -1 in Moss Vale," she said.
Taralga recorded a chilly -4.5 before dawn on Sunday, and Braidwood -3.7.
Perisher and Thredbo resorts received a dusting of snow on Saturday before clearning on Sunday, though Ms Kirkup said overnight temperatures were below zero which were great for snow-making machines.
Just before 8am on Monday temperatures for Sydney, Melbourne and Brisbane were hovering around 10 to 11 degrees, while at Albion Park it was 12 degrees.
It was brisk for other capitals around the nation also at 8am - seven degrees in Hobart, six in Canberra and 14 degrees in Adelaide.
Ms Kirkup said the forecast for this week would look similar to the past few days but the difference was in the winds, with this week feeling more like what it reads on a temperature gauge.
"The actual daytime temperatures will be similar but it's absolutely going to feel a bit warmer than it has been with that ridiculous westerly that's been coming through," the meteorologist said.
"This high pressure system becomes established over the top of us, so it's just going to be light winds mostly for Tuesday and Wednesday."
The meteorologist said there would be a southerly wind change on the coast later in the week, while it would remain "reasonably dry" for the region.