More thunderstorms as second storm hits

A second storm has started to pound the country with squally thunderstorms expected to strike much of New Zealand today.

The wild weather has started to hit the capital already with a rush hour train service between Taita and the city held up due to "adverse" weather conditions.

Motorists were also warned to take care and drive to the conditions as the weather deteriorated.

Taranaki was told to brace for thunder and lightning as it storm clouds bore down on the region just before 8.30am.

Earlier MetService duty forecaster Derek Holland said the Westland and Nelson regions were starting the day with heavy rain and thunderstorms which would spread across the North Island later in the morning.

"There will be heavy rain and squally thunderstorms in many areas, including main centres and it's acompanied by strong winds," said Mr Holland.

MetService has issued strong wind and severe thunderstorm watches ahead of today's storm spanning western regions from southern Auckland to central Westland.

The MetService warned there was a possibility of damaging tornadoes with squally winds gusts, heavy rain and hail.

Mr Holland said Auckland would see conditions deteriorate towards lunchtime with heavy rain and squally thunderstorms with strong northwesterly gales with gusts blowing more than 100kph.

He said the rain would ease to isolated showers during the afternoon with a change in wind direction.

"It's a similar story across the North Island. It just happens a bit earlier in the south," said Mr Holland.

In Wellington the rain was due to start mid-morning with squally thunderstorms hitting late morning, possibly just before midday.

Auckland would have a high of 20C but Wellington would only reach 16C.

The best weather was reserved for the east coast of the South Island which escaped today's wild weather with patchy, isolated showers.

After morning showers the skies were expected to clear to reveal a fine afternoon and a high of 18C in Christchurch.

Dunedin would also be peppered by showers throughout today clearing in the evening. It was expecting a cooler 14C.