Clear your drains and gutters to prepare for heavy rain. Avoid low-lying areas and drive cautiously.Civil Defence is monitoring incoming severe weather expected to bring heavy downpours to the North Island's East Coast in the coming days.
NIWA said concern was growing for a "significant rain event", while large gusts of more than 100km/h and large waves were possible for coastal areas.
"Combined with... wet ground, this will increase the odds for damage & power cuts," a post on the forecaster's X page said.
"Large waves will mean a risk for coastal erosion as well as possibly increasing the chance of flooding around high tide cycles over the next day or so."
Rivers could also "rise rapidly" making "flooding, slips and difficult driving conditions possible", MetService said.
Tairāwhiti Civil Defence (TEMO) said heavy rain had already started falling in the region as of 10am Tuesday.
"We've been here before and we know what to do," the agency said. "We've got the TEMO team keeping a close eye... on things and will update you as soon as we get the info from MetService."
Civil Defence urged people in the region to avoid unnecessary travel.
From 10am on Tuesday until at least midday on Wednesday, between 140 and 180mm of rain was expected to fall in Tairāwhiti/Gisborne about and south of Ruatoria, MetService said.
In Hawke's Bay north of State Highway 5, up to 240mm could fall inland and 150mm about the coast. South of SH5 could see up to 180mm about the inland ranges and 120mm elsewhere.
"The mix of large swells, strong winds and heavy rain are likely to cause disruptions around the coast, to the roads and potentially the power network," MetService meteorologist Lewis Ferris said. "The southeast swell direction could mean significant waves into the Gisborne Harbour so boaties are advised to check their moorings.
"Coastal communities should expect waves to run further up the beach around the high tides Tuesday evening and Wednesday morning," MetService said.
The deteriorating weather conditions were also hampering the search for three fishermen who went missing off the coast of Gisborne on Monday.
Gisborne Tatapouri Sports Fishing Club president Roger Faber said the weather took a "gnarly" turn while they were out at sea.
The vessel was one of three which went out chasing tuna but contact was lost when conditions became rough, Faber said.
Heavy rain warnings
Gisborne/Tairawhiti about and south of Ruatoria
Period: 26hrs from 10am Tue, 25 Jun - noon Wed, 26 Jun
Forecast: Expect 140 to 180 mm of rain inland, and 100 to 150 mm about the coast. Peak rates of 15 to 25 mm/h expected during this afternoon and evening. Note, further periods of rain or showers are forecast through the remainder of Wednesday, Thursday and Friday, but intensities and amounts are expected to be much lower. Low chance of upgrading to a Red Warning.
Impact: Streams and rivers may rise rapidly. Surface flooding, slips, and difficult driving conditions possible.
Action: Clear your drains and gutters to prepare for heavy rain. Avoid low-lying areas and drive cautiously.
Hawke's Bay north of SH5
Period: 35hrs from 10am Tue, 25 Jun - 9pm Wed, 26 Jun
Forecast: Expect 180 to 240 mm of rain inland, and 100 to 150 mm about the coast. Peak intensities of 15 to 25 mm/h during this afternoon and evening. Note, further periods of rain or showers are forecast through the remainder of Wednesday, Thursday and Friday, but intensities and amounts are expected to be much lower. Moderate chance of upgrading to a Red Warning.
Impact: Streams and rivers may rise rapidly. Surface flooding, slips, and difficult driving conditions possible.
Action: Clear your drains and gutters to prepare for heavy rain. Avoid low-lying areas and drive cautiously.
Hawke's Bay south of SH5
Period: 28hrs from 11am Tue, 25 Jun - 3pm Wed, 26 Jun
Forecast: Expect 140 to 180 mm of rain about the inland ranges and coastal hills, and 80 to 120 mm elsewhere. Peak rates of 10 to 15 mm/h expected about the ranges. Note, further periods of rain or showers are forecast through the remainder of Wednesday, Thursday and Friday, but intensities and amounts are expected to be much lower. Low chance of upgrading to a Red Warning.
Impact: Streams and rivers may rise rapidly. Surface flooding, slips, and difficult driving conditions possible.
Action: Clear your drains and gutters to prepare for heavy rain. Avoid low-lying areas and drive cautiously.
Strong wind warning
Gisborne/Tairāwhiti and Hawke's Bay from Wairoa northwards, including Mahia Peninsula
Forecast: Severe gale southerlies gusting 120 km/h in exposed places. Note, the strongest winds are expected in coastal places. Low chance of upgrading to a Red Warning.
Impact: Damage to trees, powerlines, and unsecured structures possible. Driving may be difficult, especially for high-sided vehicles and motorcycles.
Action: Prepare your property by securing items that can be picked up by strong winds. Drive cautiously.
Strong wind watch
Bay of Plenty east of Whakatāne
Period: 15hrs from 3pm Tue, 25 Jun - 6am Wed, 26 Jun
Forecast: Southeast winds may approach severe gale in exposed places. Low chance of upgrading to a Warning.
