Gisborne under heavy rain warning, North Island set for thunderstorms

As regions across New Zealand continue to recover from Cyclone Gabrielle, Gisborne, Bay of Plenty and Coromandel residents can expect more heavy rain.

An orange heavy rain warning is in place for the Gisborne region from Tolaga Bay northwards, while heavy rain watches have been issued in the Bay of Plenty east of Kawerau and the Coromandel Peninsula by MetService.

Gisborne from Tolaga Bay northwards is expected to be hit with 60 to 100mm of heavy rain from 3am Monday through till 4am on Tuesday, with localised downpours of 25 to 40mm/h likely on Monday morning.

From 9am Monday through till 3am Tuesday, the Coromandel Peninsula is expected to have periods of heavy rain with possible thunderstorms and localised downpours.

READ MORE:
* Two tropical cyclones potentially developing, impact to NZ ‘relatively low’
* Cyclone Gabrielle officially ‘one of worst storms in NZ’s living history’
* Cyclone Gabrielle: What will happen next and when will it be over?

The rainfall could approach warning criteria.

Bay of Plenty east of Kawerau is forecast to see periods of heavy rain with possible thunderstorms and rainfall potentially reaching warning criteria, between 7am to 4pm Monday.

“Surface flooding is not an unreasonable expectation as another complex trough moves through the North Island,” MetService meteorologist Alex Holden said.

“It’s already really wet, so this will just be piling it on.”

Meanwhile, a severe thunderstorm watch has been issued for much of the North Island from Monday afternoon until the evening.

The watch covers many parts of upper and central North Island between midday on Monday and 9pm, including Northland, Auckland, Waikato, the Kaimai Range, inland Waitomo, Taumarunui, southern Rotorua, Taupō, Taihape, northern Manawatū and inland Hawke’s Bay.

MetService is forecasting the thunderstorms will be slow-moving with a moderate risk of becoming severe.

Thunderstorms will bring hail and localised downpours of 25 to 40mm/h to affected regions, with the risk of surface flooding, flash flooding and slips.

Tāmaki Makaurau and Northland are expected to have scattered rain on Monday with some heavy rain from late morning. Thunderstorms are also possible from the afternoon, MetService has forecasted.

Meteorologist John Law said the risk of more thunderstorms could produce heavy downpours.

Auckland Emergency Management (AEM) issued a reminder to locals on Monday, urging them to “stay vigilant” as the threat of thunderstorms linger.

“These thunderstorms are expected to be slow moving, bringing localised heavy rain and hail for some,” AEM’s duty controller Fleur Aldridge said.

“Rainfall of this intensity can potentially lead to surface or flash flooding in low-lying areas. We also urge everyone to be cautious when driving as conditions could be hazardous.”

AEM asked Aucklanders to continue staying calm, safe and prepared to leave should conditions become dangerous.

Power has been mostly restored in Auckland’s cyclone-ravaged west coast beaches Piha, Karekare and Muriwai.

In just over three weeks, 7000 homes have undergone building assessments.

As of 10am on Monday morning, 659 homes have red placards, 2245 have yellow placards and 4116 white placards.

These figures are a combination of houses and properties damaged during the January floods and Cyclone Gabrielle.

AEM also reminded Aucklanders to stay away from the west coast, which includes Karekare, Piha, Te Henga Bethells Beach, Muriwai, Anawhata, Huia Little Huia and Whatipū.

“Please continue to stay away from these areas and expect to be turned away if you are not a resident,” AEM said.

This includes homes damaged by the January flood and Cyclone Gabrielle.

Some rain is also expected in Napier, another region hit badly by Cyclone Gabrielle.

Manawatu to Wellington and Wairarapa can expect fine spells with isolated showers.

Thunderstorms are possible from Monday afternoon in Nelson, Marlborough and Buller.

Odd showers are expected in Ōtautahi, South Canterbury, Otago, Southland, Westland and Fiordland.

Meanwhile, two tropical cyclones are potentially developing in the South Pacific this week, but MetService says the risk them directly affecting New Zealand is relatively low.

Law said it’s not unusual at this time of year to have activity up in the tropics.

At this stage, a tropical low to the north of Fiji is expected to move west, towards Vanuatu during Monday and Tuesday, and there remains a high risk for it to become a tropical cyclone.

Fiji MetService is forecasting the tropical low will be upgraded to a Category 1 Tropical Cyclone about 12pm on Tuesday near Vanuatu.

The system is expected to remain close to Vanuatu during Tuesday and Wednesday.

Another tropical low in the Coral Sea is expected to move east and move across close to Vanuatu late next week, MetService said.

Law said MetService would be closely monitoring the weather system and the situation in the tropics .

He said there could be an increase in swells and some stronger winds.