Snow is being predicted for the Desert Road as a southerly surge rushes northwards.

Once the rain has moved off New Zealand, WeatherWatch.co.nz says an entirely new weather system from the Southern Ocean will spread much colder air on Thursday afternoon.

'But the main event for cold hits on Friday PM and across Saturday as the Antarctic blast finally arrives.

'That's when the southerly surge rushes northwards up the South Island and into the North Island with temperatures tumbling everywhere.” WeatherWatch.co.nz says not one part of New Zealand will escape a temperature drop from the cold change this weekend.

'Snow may fall in Queenstown and Dunedin on Friday or early Saturday, with light flurries to low levels. Cold rain and sleet may be heavy for a time too in Southland and Otago. Alpine Highways are likely to be impacted for a time.

'The cold change races northwards overnight Friday and over Saturday brings snow showers to the Desert Road and the Rimutaka Ranges.

'We'll have a clearer time line on Thursday as this cold change starts to move in - and more details too.”