MetService weekend weather warnings: Heavy rain, thunderstorms and gales forecast

MetService has warned that a complex trough is set to hit parts of New Zealand this weekend. Image / MetService
MetService's severe weather update for April 17-22. Video / MetService

A severe thunderstorm warning has been lifted for the wider Wellington region, but flooding has closed sections of two highways north of the city.

The two closed highways are State Highway 58, Pāuatahanui to SH2 Haywards, and SH59, Mana Esplanade at Mana View Rd, NZ Transport Agency said.

A severe thunderstorm warning was issued just before 9am for the bottom of the North Island, including Wellington, Kāpiti Coast and South Wairarapa, with the thunderstorms expected to be accompanied by torrential rain and damaging wind gusts.

MetService earlier warned a complex trough was set to pummel parts of New Zealand this weekend, bringing heavy rain, possible thunderstorms and gale-force winds.

Drivers have already been told to avoid State Highway 59 at Mana, north of Porirua, with the highway closed due to flooding, NZ Transport Agency (NZTA) said this morning.

“Heavy rain has caused extensive surface flooding, and the highway is currently closed at Mana View Road. This section of SH59 remains closed until further notice ... drivers heading from Wellington to the Kāpiti Coast should use SH1 Transmission Gully.”

A crash that earlier closed SH59 to southbound traffic between Paekākāriki and Pukerua Bay had now been cleared, and the highway is open, NZTA said.

They urged drivers to take care.

“With more bad weather expected, drivers must be ready for wet weather conditions, and weather-related driving hazards across the region today.”

Heavy rain could see roads closed at short notice, and motorists should check highway conditions and weather warnings for the Wellington region before they travel.

‘Stay alert’

A string of severe weather watches and warnings is already in place for much of the country, with the risk of flash flooding in some areas.

A severe thunderstorm watch remains in place for Manawatu, Tararua, Kapiti-Horowhenua, Wairarapa and Wellington until 1pm today.

“A very active line of thunderstorms lies over northern Wellington and southern Kapiti, extending eastwards into Wairarapa. This line is moving slowly northeastwards, accompanied by very heavy rain, possibly torrential in places”, MetService said in a statement.

“People are urged to stay alert to these severe weather conditions, with flash flooding likely.”

MetService meteorologist Braydon White told the Herald a front had pushed its way up the South Island overnight and was set to gradually move over the North Island today.

White said Gisborne was one of only a few North Island regions expected to escape the wet weather until Sunday.

“Most people will be wet in the North Island [today], although in some places like Auckland it’d mostly be in the second half of the day and into the evening,” White said.

This rain could put a damper on Auckland’s sports-packed weekend, potentially affecting the One New Zealand Warriors’ clash with the Gold Coast Titans at Go Media Stadium in Penrose.

MetService has warned that a complex trough is set to pummel parts of New Zealand this weekend. Image / Windy.com
MetService has warned that a complex trough is set to pummel parts of New Zealand this weekend. Image / Windy.com

He said that alongside the rain, MetService was expecting “pretty squally thunderstorms in western areas”.

The main concern was heavy rain over short periods for localised areas.

“Unfortunately, that includes northern and eastern parts of Northland, which as we know [has] already had so much rain this year. This isn’t something that they want.”

He said MetService was not expecting this weekend’s weather to be as severe or as impactful as previous events, such as Cyclone Vaianu, but the risk of flash flooding remained.

Temperatures would be “a touch warmer” than average for this time of year, White said.

“We’re seeing low temperatures of around the mid-teens for most places. Further south [they’re] still getting some single digits, though.”

Severe weather watches and warnings

An orange heavy rain warning is in place for Taranaki north of about Eltham and King Country from 11am today until 5am tomorrow.

The same warning is in place for the Buller and the Grey districts until 11am.

The headwaters of the Canterbury lakes and rivers are under the same rain warning until 6am.

A heavy rain watch is in place for the northern and eastern parts of Northland, north of Whangārei, from 9pm until 5am tomorrow.

Tasman northwest of Motueka is also under the same watch until 3pm.

The Tararua Range, the Kāpiti coast and parts of Wellington north of Porirua are under the same heavy rain watch until 2am tomorrow.

The Richmond and Bryant Ranges are under the same watch until 3pm.

Wild weather next week

On Sunday, a “very large area of low pressure” would sit over the top of the country, White said.

“Because of that, we have a number of spiral bands of rain that kind of wrap around the low and just bring periods of rain or showers to much of the country through Sunday and into Monday.”

At the start of next week, the rain bands were expected to shift eastwards.

“Those bands, instead of passing over, they start becoming slow-moving. And that is potentially going to bring some persistent and possibly significant rain.”

He said at this stage it was still uncertain where the rain would fall, though the eastern South Island appeared most likely to be wet through the beginning of next week.

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