MetService meteorologist John Law said a band of rain would then brush the top of the North Island tonight and tomorrow, “keeping Northland, Auckland and the Coromandel on the wetter side”.
Fellow meteorologist Surprise Mhlongo told the Herald there was a low risk of thunderstorms tonight, but that would increase to a moderate risk before dawn tomorrow.
“The weather will just deteriorate from tonight into tomorrow morning.”
The latest bad weather comes just days after thunderstorms, intense downpours, gusty winds and tornadoes wreaked havoc in parts of the North Island.
Wellington was plunged into a State of Emergency on Monday, with many rattled awake to evacuate. The severe weather also led to the death of Karori resident Philip Sutton, who was swept away by flash flooding.
Severe weather watches and warnings
An orange heavy rain warning is in place for eastern Northland from 2am tomorrow until 8pm.
Great Barrier Island is under the same warning from 8pm tonight until 2pm tomorrow.
Eastern Auckland, north of Whangaparāoa, has also been issued an orange heavy rain warning from 1am tomorrow until 4pm.
MetService said this rain might be accompanied by thunderstorms and warned that streams and rivers could rise rapidly.
Surface flooding, slips, and difficult driving conditions were also possible.
From 4am until 10pm tomorrow, a heavy rain watch is in place for Eastern Northland, about and south of the Bay of Islands, not included in the warning.
Coromandel Peninsula, north of Whitianga, is under the same watch from 11pm tonight until 1pm tomorrow.
What is in store for Anzac weekend?
Law said most regions were expected to remain dry during Saturday’s dawn services.
A few early showers were possible on the eastern coast of Northland, which could affect some events.
“Dawn services are looking mostly dry, but it will be a cold start, especially inland.
“Waiouru is set to be one of the coldest spots, with temperatures around 1C at daybreak.”
MetService said that, while nights would remain chilly, plenty of sunshine would help to lift daytime temperatures, particularly across the eastern South Island.
Anzac Day dawn service at the Auckland War Memorial Museum last year. Photo / NZME
After a run of cooler days, Canterbury and Otago are expected to be the warmest parts of the country this weekend, with Dunedin forecast to reach about 22C on Saturday.
MetService said this was 5C above average for this time of year.
The final day of the long weekend, on Monday, would be settled for most regions.
“There will be a few showers pushing into Southland and parts of the West Coast, but for many, especially those recently affected by severe weather, it will be a welcome break,” Law said.
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