The Metservice website said a moist northeasterly flow will bring rain to many parts of the country.
Meteorologist Rebekah LaBar said it will be a showery end to the school holidays in Hawke's Bay.
"We're expecting the northerly wind to bring milder temperatures with a somewhat wet week. No more snow is expected on the Hawke's Bay hills."
It is forecast to be fine tomorrow evening, just in time for the Magpies v Horowhenua 7:30pm kickoff at McLean Park. But after tonight's rain, the home turf might be a bit soggy.
Night-time lows will be higher at 8C tonight, but will drop to about 3C by the weekend.
Metservice is forecasting more overnight frosts with fine days in the two cities next week.
The icy ground is not a problem yet for farmers and growers.
"It is winter," Kirsty Hill said at her Waiwhenua farm.
"We've just got to wait for it to thaw so we can get things done."
But the region's growers will need rain to get more moisture in the ground before spring, said Ngatarawa chief winemaker Alwyn Corban.