Thunderstorms are on the cards for most of the North Island tomorrow as the wild weather which pelted the West Coast today moves up the country.

Niwa has tonight warned there is a risk of heavy downpours, thunderstorms and gusty winds right across the North Island.

MetService meteorologist Claire Nickson said by tomorrow morning the rain band would have moved away from the West Coast of the South Island and on to the North Island.

⚠️ Heads up, North Islanders!

An active front will track across on Thursday, with the risk for:

🌧️ Heavy downpours
⚡ Thunderstorms
💨 Gusty winds

Plan your day with the weather in mind. pic.twitter.com/lgl1VkKMMb

— NIWA Weather (@NiwaWeather) April 10, 2019

"That front will be bringing rain to most places really as it gradually makes its way over the North Island," she said.

"We don't have any watches or warnings out for any North Island areas but we're still expecting there'll be brief heavy rain and also a risk of thunderstorms."

The rain band was likely to not affect Auckland until tomorrow afternoon but there was a chance of thunderstorms.

The rain could briefly become heavier with a chance of thunderstorms, Nickson said, with the possibility of wind gusts of up to 90km/h.

Ferocious weather destroyed the Waiho Bridge near Franz Josef last month and as contractors worked to rebuild it today, the region was being pelted again.

New Zealand Army personnel work on the replacement Bailey bridge over the Waiho River. Photo / NZDF

A wild front pushed heavy rain and thunderstorms over the West Coast today with parts of the region taking on over 100mm of rain in the last 24 hours.

MetService meteorologist Claire Nickson said by mid afternoon, Milford Airport had received 129mm, Franz Josef Glacier 108mm and Haast 50mm.

"The rain band is still hanging around that area now but it will begin to move north later on this evening, then it will ease for the Franz Josef area," she said.

"The warning goes out until 3am Thursday and that will ease for the southernmost areas first and then it will move north."

The bridge over the Waiho River was washed away last month. Photo / Supplied

The Waiho Bridge was destroyed on March 26 after extensive rain caused the Waiho River to flood and wash away the Bailey bridge.

Weather permitting, work today was focusing on completing the bridge launch, installing the new bridge spreader beams and fully dismantling the old bridge.

Elsewhere, a washout has forced emergency services to close State Highway 6 between Makarora and Haast.

The NZ Transport Agency reports the flooding took place near Dianna Falls and the road is expected to be closed until 9am tomorrow.