The MetService expects temperatures to pick up again on Tuesday, as the cold weather continues this weekend.

Several roads will hold hazards in the form of ice tonight as temperatures plummet to what for many could be the coldest night of the year so far.

Saturday night was cold for several towns, with Waiouru dropping to -6.5C and Mt Cook airfield to -5.7C.

'Cloud that kept eastern parts warmer last night will have moved off tonight, so many parts of New Zealand will record sub-zero temperatures tonight,” says meteorologist Tom Adams.

'This will bring frosts as far north as Northland, and icy roads countrywide.”

This weekend's snow fell from a cold front, which was followed by strong south-westerly winds.

These winds have whipped up a sizeable swell in the Southern Ocean, the peak of which is due to reach New Zealand's eastern coastline today.

A wave buoy in the Cook Strait has been recording average wave heights of five to six metres throughout Sunday, with the biggest waves reaching heights of as much as eleven metres.

Although swells will have reduced by high tide tonight, motorists are advised to drive with caution on coastal roads.

Looking ahead, settled weather continues into the start of next week. Temperatures pick up on Tuesday as the winds swing around to the northwest and a spell of patchy rain returns to western parts.

Showers will spread to other parts during the week, but the risk of further severe weather this week is low.