Parts of New Zealand are set to swelter in the warmest spell the country has seen since autumn.

While the West Coast is under a heavy rain warning, temperatures in eastern regions of the North Island will rise to the mid-20s as a very warm northerly flow envelopes coastal regions.

Hastings is set to enjoy a taste of summer enjoying a balmy, fine 24C while neighbouring Napier and Gisborne will enjoy 23C for the next two days.

Even Blenheim will hit 21C.


"A warm northerly flow is coming across the Tasman. That's what's going to bring the temperatures up," said MetService meteorologist Tuporo Marsters .

But the warm temperatures would only be temporary before more disturbed weather struck as another cold front swept in from the Tasman Sea.

Meanwhile there was no let up for western regions with rain drenching central and southern New Zealand today. The heaviest falls were expected in Fiordland and Westland and on the Tararua Range and Mt Taranaki.

A second front was expected to hit the West Coast late on Thursday dumping even more heavy rain across the region.