Waiho River at Franz Josef in April when Westland was hit by heavy rain.
Photograph: RNZ/Maia Ingoe

The West Coast and South Island headwaters will see “significant” rainfall this weekend, with orange heavy rain warnings in effect until Saturday, MetService said.

The forecaster said a front would bring heavy rain to the western and southern parts of the South Island, although much of New Zealand will experience warmer than normal temperatures in the coming days.

Helen Lash
Photograph: Westland District Council / Provided

Westland’s mayor said the area was prepared if heavy rain caused disruption and flooding.

Helen Lash said it had been raining steadily in the area on Friday and there was already surface flooding in South Westland, with more rain expected in these areas overnight.

“The regional council’s river management staff are already present in all major areas of South Westland, with police on duty in all these towns if needed. We’re not waiting to see if we get a civil situation. It’s a defensive situation; we’re putting everyone on the ground.”

Lash said organizations are monitoring the situation closely.

He was aware that there were many people visiting the area who were unfamiliar with the conditions.

“People from abroad are not used to driving in these conditions and when you round a bend there’s a foot of water in front of you and if you’re going fast you can go off the road.

“And we normally ask people to drive carefully in these conditions and if you don’t need to be out in the dark of the night, if there is surface flooding on the roads then they shouldn’t put themselves in that position.”

Police said some roads were closed in the Haast area due to flooding on Friday night. They asked citizens to be more careful.

Emergency Management Minister Mark Mitchell said hydrologists were closely monitoring the Waiho River at Franz Josef as heavy rain continued to fall.

MetService had issued an orange rain warning for Westland, with up to 400 millimeters of rain expected to fall in the area by midday on Saturday.

Mitchell had gone to the West Coast to visit Franz Josef to see how the Waiho River was coping with the predicted flood.

He said the river was the area of ​​greatest concern.

He said the weather looked good Friday night, but hydrologists were monitoring the situation as heavy rain was forecast.

Mitchell said Westland residents should stay off the roads unless travel is absolutely necessary.

Westland’s emergency operations center remained on standby.

Rain and wind throughout Motu

The following orange heavy rain warnings are in place:

• Gray and Buller Districts Saturday 01.00-21.00; 100 to 130 mm of rain is expected in mountainous areas, with less rain expected along the coasts. Peak speeds of 15 to 25 mm/hour on Saturday morning and afternoon.
• Westland until 13:00 on Saturday; On top of the falls, 250 to 350 mm of rain is expected around mountain ranges (possibly more in local areas) and 100 to 130 mm near the coast (especially around the Glaciers). Peak rates of 25 to 35 mm/hour are expected in these ranges.
• Canterbury spring, south of Arthur’s Pass, from 9am Friday to 12pm Saturday; On top of the falls, 250 to 350 mm of rain is expected in the main section and 150 to 200 mm within 15 km further east. Peak rates of 25 to 35 mm/hour are expected regarding the split.
• Otago headwaters until 6am on Saturday; 80 to 140 mm of rain is expected in the main part, and 50 to 80 mm in 15 km further east. Peak rates of 15 to 20 mm/hour are expected regarding the split.
• from Fiordland around George Sound and north to 3am on Saturday; 80 to 100 mm of rain is expected to top the falls. Peak speeds of 10 to 20 mm/hour.

There is a moderate chance of moving to a red heavy rain warning for Westland, a low chance for Canterbury and a minimal chance for Grey, Buller, Fiordland and Otago.

A strong wind is observed from midnight Friday to noon Saturday for the Canterbury highland, where northwesterly winds could approach severe gale force over exposed areas.

Northwest winds could also be gusty in Wairarapa, Wellington and Marlborough, MetService said.

It was definitely a hot night in Aotearoa New Zealand, Oamaru was 20 degrees at 7am!
The hot trend continues towards Saturday. pic.twitter.com/Xx9m9UGhSD

— MetService (@MetService) November 7, 2024

Elsewhere, warm temperatures will cover New Zealand, while fair, dry and warm conditions will be experienced in the east and north, MetService said.

In some places, such as Hawke’s Bay, temperatures can reach 30 degrees Celsius.

On Saturday, the North Island will be partly cloudy with scattered showers, and rain will later develop in the southwest. In addition to areas affected by heavy rain warnings, the South Island will see light rain and isolated showers.

Sunday will see rain, heavy rainfall in the west of the North Island and a few showers elsewhere. Rain will develop in the south-west of the South Island, while elsewhere there will be light showers and isolated showers.

hotter than ever

MetService meteorologist Lewis Ferris said much of the country was already experiencing hot and humid conditions.

“This will help continue the very heavy rain we will see along the West Coast of the South Island for the remainder of Friday into Saturday.

“Parts of the Westland Ranges could see up to 400mm of rain in about 27 hours until midday on Saturday, so it will be quite heavy rain.”

Wet weather was due to reach the North Island on Sunday, but it was not expected to be this severe.

This comes as the country is experiencing higher-than-normal temperatures as warm air moves across the Tasman from Australia.

“Some areas on the east coast of both the North and South Islands are starting to get quite dry and we’ve had a series of warm temperatures that look set to continue into the weekend along with strong north-west winds, increasing the risk of fires so people need to be a bit more careful.”

West Coast Emergency Management Manager Claire Brown said she was closely monitoring severe weather forecasts in the Westland from Friday through Saturday morning.

“It is not unusual for these areas to receive this amount of rainfall, but as always we need to monitor closely and be ready to take action if necessary, particularly for the Westland region.”

An agency briefing was held on Friday morning to share information and planning arrangements. Community coordinators were contacted and West Coast Emergency Management was working closely with partner agencies.

People were warned that rivers could rise rapidly, surface flooding and slides were possible and driving conditions could be hazardous.

road closure

The Milford Sound Highway was closed as a precaution amid fears that warm rain and melting snow could lead to late-season avalanches.

MetService and NZ Transport Agency/Waka Kotahi have warned motorists around Clutha and Southland that they may experience very wet conditions on Friday afternoon.

NZTA’s central South Island systems manager Mark Pinner said people should do this check traffic pages Before you set off, be prepared to take a break in case the rain gets harder and visibility decreases.

Highway crews were prepared for heavy rain and were monitoring spots where slides have caused highway flooding in the past, such as Muddy Creek and State Highway 6 in Otago.

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