MetService said the front moving east from over the Tasman Sea was likely to affect the country until tomorrow.
“A low and associated fronts over the Tasman Sea are expected to move east to affect the country from tonight through to Tuesday, bringing strong winds and heavy rain to many parts of New Zealand,” the forecaster said.
“Heavy rain warnings and watches remain in place for northern and western parts of the country, and strong wind watches are also in force for the upper North Island.
“People are advised to stay up to date with the latest forecasts in case any changes are made, or further areas are added.”
Meanwhile, Auckland train users are facing disruptions due to a power outage.
Despite power being restored Southern and Eastern line services are experiencing delays, Auckland Transport said in an alert.
“Due to trains and crew being out of position, Southern Line trains will run at a reduced frequency,” AT said.
“The Eastern line trains are also seeing delays.”
Waka Kotahi NZ Transport Agency is alerting morning rush-hour commuters to take precautions on Auckland’s Southern Motorway following a crash.
It was reported at 7.50am and had blocked “the right southbound lane under Mountain Rd overbridge, between Grafton Rd on-ramp and Gillies Ave off-ramp”, the agency said.
“Merge with care to pass and expect delays.”
A previous crash was now cleared on the same motorway, it was reported at 6.45am.
It is “part-blocking” the right northbound lane on State Highway 1 prior to the Drury interchange, Waka Kotahi said.
The agency said motorists should pass with care and allow extra time.
A police spokesperson said they continue to advise the “public to pay close attention to weather forecasts and emergency management updates” given the current weather conditions across the Auckland district.
MetService had earlier said the system would bring heavy rain to the top of both islands and the Bay of Plenty.
It warned Northlanders to brace for a night of rain as an orange heavy rain warning is in force and lasts until 6am today.
The region was told to expect thunderstorms, up to 80mm of rain and peak rainfall rates of up to 25mm an hour.
Northland and Auckland are also under strong wind watches.
An orange heavy rain warning has been issued for Bay of Plenty and areas west of Whakatāne, including Rotorua, from 5am to 9pm today.
MetService said thunderstorms and up to 90mm of rain were possible for the area.
At 9am today, an orange heavy rain warning is coming into force for areas east of Whakatāne and Gisborne north of Tokomaru Bay. Thunderstorms are possible and there could be up to 140mm of rainfall about the ranges.
In the South Island, orange heavy rain warnings have been issued for Tasman, west of Motueka, and Westland, south of Otira.
Tasman’s warning began at 2am and will be in place for 15 hours, while Westland’s comes into effect at 5am but will be in place for 37 hours.
There are also heavy rain watches for Buller and Fiordland and the Richmond and Bryant ranges.