Civil Defence has also urged Coromandel residents to “stock up on supplies, batteries and gas, check and clear drains in your neighbourhood”.
They have been told to tie down outdoor furniture and “review plans should you become isolated due to slips and flooding”.
“Those living close to the sea need to prepare for wave surge by having a plan B and somewhere to go, especially if the surges increase during the main high tides: 8am and 8pm Sunday and 9am and 9pm Monday,” Civil Defence said.
Northland, Auckland and the Coromandel Peninsula can expect cloudy periods for most of the day today.
From the afternoon, isolated showers will begin in eastern Coromandel and Northland turning to rain in the Far North tonight, the MetService said.
The middle and lower North Island will buck the trend today with a mostly sunny forecast.
On Sunday the rain in Northland will likely spread south and reach Taupo late, with some heavy falls developing, MetService said.
MetService warnings and watches for heavy rain and severe easterly gales are in force for parts of northern New Zealand on Sunday and Monday.
An orange heavy rain warning is in place for Northland, Coromandel Peninsula and Tairawhiti from Sunday to Monday.
MetService also warned heavy rain may cause streams and rivers to rise rapidly, surface flooding and slips are also possible and driving conditions may be hazardous.
Those in the warning areas can expect 100 to 150 mm of rain and peak rates of 15 to 25 mm/h from Sunday night to Monday morning, with thunderstorms possible.
An orange strong wind warning is in place for Northland, Auckland and the Coromandel Peninsula from Sunday to Monday.
MetService warned strong wind gusts could damage trees, powerlines and unsecured structures. Driving may be hazardous, especially for high-sided vehicles and motorcycles.
Severe gale easterlies with damaging gusts of 130 km/h are forecast in exposed places.
Areas that should also expect periods of heavy rain from Sunday night are Auckland and Great Barrier Island and the Bay of Plenty north of Tauranga.
Areas that should also expect periods of strong wind from Sunday night are Auckland south of Whangaparaoa, the Kaimai Range and eastern Waikato.
Eastern and northern coastlines are also set to be pummelled by monster 6m waves as king tides combine with strong onshore winds on Sunday.
The South Island can expect a mainly fine Sunday, but there will still be some isolated showers in the far south.
Tens of thousands of people are set to run the Auckland Marathon tomorrow in heavy rain and gales.
A spokeswoman for the Auckland marathon organisers told the Herald there was a contingency course if Waka Kotahi NZTA had to close the harbour bridge because of high winds.
If the course does change, the whole race will take place on the city side of the bridge, and participants will be directly contacted by race organisers, the spokeswoman said.
Organisers have been liaising with MetService and will have a final meeting with forecasters this morning.
