A severe weather warning has been issued for the South Island this weekend, with heavy rain and gales force winds expected to move north on Sunday.

Metservice forecasters are predicting a cold front will move over the Tasman Sea to Fiordland late on Saturday night, across the South Island on Sunday morning and onto the North Island by Sunday afternoon.

Heavy rain warnings are already in place for Fiordland and South Westland, and severe gale warnings in Otago, Canterbury, Wairarapa and Hawkes Bay.

"There's a fairly active weather front coming through," said Metservice meteorologist Daniel Corbett.


He said there will be "strong, potentially damaging winds" for places like Wairarapa and Hawkes Bay, and Auckland will get windier over the weekend.

"Auckland on Saturday is going to be OK but the end of Saturday we've got the rain on the doorsteps of central New Zealand."

The rain will be heading north on Sunday too so it will be "a different prospect" for those with outdoor plans, he said.

However, Corbett said the weather system "will have lost its guts" by the time it reaches Auckland.

"It's windy, it's wet the further South you are over the weekend."

A cold snap has already hit the South Island this week, with some inland areas experiencing frosts and close to freezing temperatures.

This time of year is "a bit of a rollercoaster ride," said Corbett.

"Even though they say climatologically we are heading into summer, meteorologically summer doesn't happen until the third week of December."

- nzherald.co.nz