He said the rain would be especially prominent in the eastern parts of the South Island.
Miller said the good news for those celebrating the lead-up to the new year outdoors was that many of the severe weather watches and warnings were likely to expire in the morning.
“I do want to emphasise that even though the rain is going to be easing for most of the North Island, it’s still going to be rather unsettled,” Miller said.
“There’ll be lines of showers going through, especially for the northern parts of the North Island, but definitely that heaviest rain will be sort of clearing out,” he said.
Miller said that although there was an easing trend, Wellington would hang on to the stronger winds it had been experiencing.
‘Mixed bag’ for the South Island
Miller said the eastern areas of the South Island are in for a day of heavier falls.
The heaviest falls are forecast to hit in the morning into the afternoon for Marlborough and North Canterbury.
Further south into Southland and Central Otago, rain is likely to be minor, with drizzle or occasional showers in eastern Otago, he said.
“A little bit of a mixed bag for the South Island areas, depending on where you are,” Miller said.
This comes after a day of wild weather that battered much of the North Island.
Music festivals were disrupted, dozens of power outages hit parts of Auckland and trees and roofs were ripped away by severe 120km/h winds.
Severe watches and warnings
Most of the North Island weather alerts are set to expire today, while parts of the south will be hit by watches and warnings, impacting travel to and from major holiday and festival hotspots.
Gisborne/Tairāwhiti was under an orange heavy rain warning that expired at 3am this morning.
Bay of Plenty, about and east of Rotorua and Hawke’s Bay, were also under an orange heavy rain warning until the early hours today.
An orange strong wind warning, which signals the threat of winds gusting up 120km/h, is also in place for several regions.
Marlborough Sounds, Nelson, and the districts of Buller, Grey and Westland north of Mount Cook are under the warning until 1pm.
Manawatū, Horowhenua, and the Kāpiti Coast are also under the same wind warning until 9am.
The Tararua District and Wairarapa are under a heavy rain watch until 3pm this afternoon, while the Kaikoura Coast remains under the watch until 9pm.
Wellington is under a strong wind watch until 9pm tonight.
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