Residents across south-eastern Australia have woken to a bitterly cold morning with frost biting hard across the region.

Sydney recorded a minimum temperature of 7.3 (two below average), Melbourne 4.7 (two below average) and Brisbane 8.5 (three below average), Brett Dutschke, senior meteorologist at Weatherzone said.

Clear skies and very dry, light winds are largely responsible for the frosty morning, aided by a cool air mass, left behind by a front that passed through a few days ago.

Frost has been severe in parts of New South Wales and Victoria, threatening to cause damage to crops.

Some places have experienced their coldest morning in several years.