Cold air swept through the southeast behind a front yesterday bringing a bone chilling morning only 24 hours after some exceptionally warm nights. New South Wales, Victoria and South Australia all felt the cold, a result of some cold air that had moved in behind a front and some clear overnight skies. The front cleared eastern New South Wales in the early hours, taking strong winds and showers with it. Behind, high pressure moved in allowing the mercury to plummet under clear skies this morning. In New South Wales, minimums tended four to eight degrees below average across the southern inland in particular. Goulburn Airport fell to minus seven, eight below average and their coldest August night in six years. Thredbo's minus nine, six below average, was their coldest in a month. In Victoria, the inland froze as the mercury fell to seven below average. Mildura hit minus one, their coldest August night in 10 years. Tatura's minus three, their coldest in 12 years for August, was remarkable after an unusually warm 11 degrees the previous night. South Australia saw minimums between two and seven below average. Adelaide's 3 degrees was their coldest night in a month.