Forecasters are warning there is a risk of further slips in areas already devastated by Cyclone Gabrielle with heavy rain and thunderstorms expected to pummel the east coast.
An orange heavy rain warning has been issued for Hawke's Bay, which was one of the places hardest hit by Cyclone Gabrielle last week.
"Significant accumulations of rain expected in areas recently affected by Cyclone Gabrielle," MetService said.
The warning is currently in place until 10am Saturday.
"Expect 150 to 200mm of rain about the ranges and also away from the ranges north of Hastings (this includes the Esk Valley area and the Wairoa District), and 75 to 100mm elsewhere. The heaviest falls are likely from 3pm Friday, with peak rates of 20 to 30mm/h possible," MetService said.
NIWA principal scientist Chris Brandolino told AM on Friday afternoon and night rain could fall pretty heavily at times in parts of Hawke's Bay, bringing a risk of further landslips.
"Because the ground is so wet that really does elevate the threat for things like slips," Brandolino said.
Thunderstorms are expected to develop on Thursday afternoon for parts of the east coast of the North Island, with warnings they could become severe.
MetService has issued a severe thunderstorm watch for Coromandel Peninsula, Waikato and Bay of Plenty from 3pm until 10pm Thursday. Gisborne has also been issued a severe thunderstorm watch from 1pm until 10pm Thursday.
The weather forecasting agency said some of these thunderstorms may become severe, producing downpours with intensities of 25 to 40 mm per hour.
"Rainfall of this intensity can cause surface and/or flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips," MetService said.
"Driving conditions will also be hazardous with surface flooding and poor visibility in heavy rain."
A Heavy Rain Watch remains in place for Gisborne and Wairarapa (including the Tararua District) and now also covers Auckland, Coromandel Peninsula and western Bay of Plenty.
MetService has issued a heavy rain watch for Auckland, Coromandel Peninsula, Gisborne and Bay of Plenty about and west of Te Puke. These are in force from Thursday and Friday until Friday night/Saturday morning.
MetService said thunderstorms are possible in the regions.
A heavy rain watch has also been issued for Wairarapa from 1am until 8pm Saturday. Showers in the area are expected to continue on Thursday and Friday before turning to more widespread rain early Saturday morning, MetService said.
Extended forecast
After heavy rain this weekend, Brandolino said the country is in for a settled period during late February but then the unsettled weather could pick back up again in March.
He told AM the tropics are going to become more active which is a "red flag" that the weather could become more active in New Zealand.
"It looks like the first week or two of March we have to keep our eyes peeled to the north and north-west for any kind of visitors to the north, it doesn't have to be a tropical cyclone, it could be a whole bunch of rain or moisture," Brandolino said.
Brandolino said there could be more weather activity for the first two to three weeks of March.
"It looks like a good chunk of March could be unsettled for much of northern and eastern parts of the country."
