Parts of Australia's southeast have shivered through their coldest August morning in over 50 years. If there was ever a day to stay in bed that bit longer it was Sunday, with overnight temperatures plunging below zero across New South Wales, Victoria and the Australian Capital Territory. In New South Wales Narrandera in the Riverina dropped to minus five which is nine below average and the coldest August morning in 40 years. Those in Cooma awoke to a very frosty morning with a low of -10.6 degrees while at Perisher Valley it dropped to a bone chilling -13. Sydney didn't escape the chill with the western suburbs of Campbelltown, Camden and Richmond all dropping below zero. The city itself had a minimum of just 5.5 degrees, the coldest in four years. Canberra chilled to minus six making it coldest morning in over a year. In Victoria, Ballarat chilled to -4.6 degrees which was the coldest August morning in 51 years and the coldest of any month in 12 years. At 7:30am it was only 1.4 degrees in Melbourne which is the coldest morning since 1998. At the same time Avalon was sitting on -3.2, the coldest in 17 years. The frigid conditions where brought about by a combination of a very cold airmass, clear skies and light winds. A robust cold front moved through the nations southeast on Thursday and Friday, bringing a very cold airmass with it. A high pressure system behind the front allowed skies to clear quickly and winds to become light. The perfect ingredients for cold nights and mornings. Although tomorrow is unlikely to be as cold the slow-moving high will bring a couple more cold mornings over the coming days.