MetService says heavy rain, thunderstorms and strong winds will push across much of New Zealand from Thursday, with Taranaki at risk of warning-level falls.

A trough embedded in a humid northerly air flow is expected to bring heavy rain on King's Birthday.

Live - MetService is urging those in Golden Bay, Nelson, and the entire Northland region to prepare for potential flooding.

Up to 200mm of rain is possible in Northland, while Kaitāia has already had 30mm.

A raft of severe weather warnings and watches are in place for the West Coast and top of the South Island, and for much of the upper North Island.

MetService says heavy rain, thunderstorms and strong winds will push across much of New Zealand from Thursday, with Taranaki at risk of warning-level falls.

MetService warns thunderstorms could bring gusts up to 100km/h.

Heavy rain watches and warnings have been issued for Taranaki, Horowhenua, Kāpiti, and Wellington from late Thursday evening.

Orange heavy rain alerts are active for Taranaki and eastern Bay of Plenty.

Temperatures will drop to seasonal averages after what has been a warm start to winter.

Temperatures will drop to seasonal averages after what has been a warm start to winter.

There is still a chance of heavy showers but the general trend is an easing of the rain that slammed into the country in the past two days.