More rain on the way for flood-hit Buller, thunderstorms risk forecast from Southern Westland all the way up to Waikato

Wednesday, 21 July 2021

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More heavy rain is forecast for Buller and other areas hit hard by the weekend deluge and flooding.

MetService has issued a heavy rain warning for Buller and the ranges of Westland for an 11-hour period, starting from about 6pm on Wednesday till 5am on Thursday.

Much of the rest of Aotearoa will also see rain late Wednesday or early Thursday with thunderstorm risk from Southern Westland all the way up to Waikato.

The forecast for rain comes as Buller residents begin to assess the damage from severe flooding over the weekend that displaced hundreds of people.

Donation Drive has been set up by Samara File and her husband to help people get back on their feet after floods in Westport.

MetService meteorologist Tui McInnes said the region could expect showers on Wednesday morning, turning to rain in the evening when the warning will “kick-in”.

Only 40-60mm of rain was forecasted, which McInnes said would not normally trigger a heavy rain warning, but due to the significant rainfall over the weekend, the warning was issued.

Thunderstorms were also forecasted in localised areas which could bring exacerbated rainfall, up to 15-20mm in an hour at peak times, he said.

More rain is expected to fall in flood-hit parts of the West Coast overnight on Wednesday.

A heavy rain warning was normally issued when 50mm of rainfall was expected over a 6-hour period, or 100mm in 24 hours.

Buller District Mayor Jamie Cleine said the warning was being monitored but had no immediate concerns.

“It’s likely to just be wet weather for a couple of days, which obviously doesn’t help people who are trying to clean up their properties.”

Rain in Buller was expected to linger on Thursday but to ease throughout the day and into Friday.

The West Coast would be most significantly hit by the forecast rain, but the frontal system was expected to move across the country throughout Wednesday, McInnes said.

“Most areas will experience some wet weather.”

East of the ranges would be drier in both the North and South Island, while the western areas would be more exposed, he said.

As of 3pm on Sunday, 158mm of rain had fallen in Westport, while Reefton, in inland Buller, received 168mm of rain. Weather stations higher up in the ranges, towards Murchison and Nelson Lakes National Park, recorded more than 300mm over 60 hours.