Flooding has closed roads, surrounded a community hall in Central Hawke’s Bay, and cut power and cellphone coverage and stranded a coastal community in nearby Tararua.

By 12pm on Tuesday a flood alarm on the Wainui River, which runs through the coastal community of Herbertville, had been triggered according to Civil Defence Manawatu Whanganui.

Herbertville Campground was being prepared for evacuation as a result, it said.

MetService on Tuesday morning issued a heavy rain warning for all of Hawke’s Bay south of Tūtira until 3am on Wednesday.

Flooding at Omakere Community Hall in Central Hawke's Bay. Photo / Omakere School

MetService said to expect 80 to 110 mm of rain to accumulate about the ranges and coastal hills, and lesser amounts elsewhere, in addition to rain that had already fallen by 9am on Tuesday.

It said the warning amounts were unlikely near the coast north of Cape Kidnappers.

Heavy rain fell across the region overnight, with severe thunderstorms striking coastal areas south of Cape Kidnappers.

Several roads have been closed in Central Hawke’s Bay, and the district council was advising people to stay away from beaches and river mouths and avoid streams and drains on Tuesday morning.

In a social media update on Tuesday morning, Central Hawke’s Bay District Council said high tide was due at 8.20am, and king tides were being experienced.

Coastal areas, particularly in Omakere and parts of Elsthorpe, suffered “wild weather” according to the council update.

A webcam view of Pourerere Beach at 8.30am on Tuesday morning.

On Tuesday morning, Pourerere Rd, approximately 20km past Omakere Hall Rd, and Elsthorpe Rd, approximately 15km past St Lawrence Rd had closed.

Herrick St (Taylors Slab), in Ongaonga, is closed and signage is in place.

Blackhead Ford was blocked and will be cleared when conditions allow.

Farm Rd was closed due to a tree blocking the road, but has since reopened.

The Omakere Hall was also pictured surrounded by floodwaters.

Hawke’s Bay Regional Council’s telemetered rainfall figures said 95mm of rain had been recorded at Omakere from midnight to 9am on Tuesday.

Flooding at the Omakere Hall in Central Hawke's Bay at 9am on Tuesday. Photo / Central Hawke's Bay District Council

A police spokeswoman said police were called about 6.30am with a report of large flooding on State Highway 2, near Ōtāne.

The northbound lane was blocked, and police were stood down as a resident cleared the drain. The road was clear about 7.10am.

The council said there had also been reports of debris on Pourerere Beach Rd.

“Our teams are out across the network assessing and clearing the roads.

Elsthorpe Rd in Central Hawke's Bay on Tuesday morning just before 9am. Photo / Central Hawke's Bay District Council

“Beware of fallen trees and power lines, avoid streams and drains as you may be swept away in flash flooding.

“Please drive carefully and call us on 06 857 8060 if you see any debris or trees on the roads.”

A Hawke’s Bay Regional Council spokesperson said on Facebook they were monitoring conditions related to the orange heavy rain warning south of Tūtira.

“Overnight there was some heavy rain in Central Hawke’s Bay, with reports of surface flooding and high levels in the smaller side streams.

“Our flood forecasting suggests the rainfall and runoff will fill the main rivers approximately to the top of bank, but should not cause issues beyond riverbanks.”

Tararua District

Tararua District Council is advising people to avoid all unnecessary travel in the district after heavy rain isolated communities and cut power and cellphone coverage.

The Herbertville Campground is being prepared for evacuation. Photo / Civil Defence Manawatu Whanganui

MetService said a heavy rain warning in Tararua until midnight Tuesday had a low chance of being upgraded to a red warning.

It said to expect 70 to 90 mm of rain to accumulate about the ranges and coastal hills, and lesser amounts elsewhere.

This is in addition to the rain that has already fallen with peak rates of 5 to 15 mm/h.

A fast-moving storm cell passed over the coastal Tararua area around Ākitio and Herbertville on Monday night, bringing “very heavy rainfall” in a short period, the council said.

The Ākitio weather station recorded 70mm of rain in just one hour between 9.00pm and 10.00pm.

“While the main rain band initially moved north earlier in the evening, rain has since resumed across much of eastern Tararua, east of the Puketoi Range.

“We are asking people to avoid unnecessary travel and check conditions before heading out.”

Herbertville was without power and cellphone coverage, though internet access was still available in some areas, the council said.

“We’re working with the Herbertville Civil Defence Group and encourage Herbertville residents with needs or concerns to reach out to us on 06 374 4080, through a Facebook message or through Antenno.”

One family in Ākitio chose to relocate to a safer location as a precaution, but at this stage, no mandatory evacuations have been required, it said.

Ākitio was “cut off” due to slips on Coast Road and River Road.

“Roading crews are on site this morning now that daylight conditions allow, and work is under way to restore access, hopefully by today.”

It was estimated around 12pm that the large slip would take approximately three to four hours to clear.

Civil Defence Manawatu Whanganui posted a photo to social media that showed the slip that had cut off Ākitio on Tuesday. Photo / Civil Defence Manawatu Whanganui.

Overnight, Manawatū-Whanganui Emergency Management Group monitored rainfall and staffed a Group Emergency Coordination Centre overnight.

In a 1.26am update, the group said the weather was “quite volatile and unpredictable”.

People in Herbertville reported rain, thunder and lightning storms in the area.

Ākitio in the Tararua District at 9.16am on Tuesday. Photo / Horizons Regional Council webcam

Heavy rain to the east of the Tararua District was coming in batches of heavy falls, which had caused rivers and streams to rise suddenly.

High tide was forecast for about 7.30am today.

According to Horizons Regional Council‘s environmental data monitoring network at 7am, the Ākitio River at Cadmus Bridge had 150mm of rain since 1pm Monday, Wainui River at Wimbledon had 100.2mm, Owahanga River at Owahanga Station had 114.4mm.

Heavy rain was expected to continue to fall in the Tararua District and surrounding area for the next 24 hours, including on the Tararua and Ruahine Range.