MetService has issued the latest New Year’s Eve forecast and it looks like we’ll be ushering in 2024 indoors this year.

From mid-afternoon today, Sunday, December 31, the muggy weather will give way to showers, building during the evening to persistent and at times heavy thundery falls before easing in the early hours of New Year’s Day, Monday, January 1.

Warning amounts of rain in some areas could cause rivers and streams to rise quickly.

North Island

Fronts move northeastwards over the North Island today with bands of rain and possible thunderstorms. A southwest flow spreads over the South Island with rapidly cooling temperatures aloft.

In the North Island, there is a moderate risk of thunderstorms about northern and western areas from Northland to North Taranaki, and also about the central high country and Bay of Plenty, mainly this afternoon and evening, but for Taranaki this morning and afternoon.

A low risk of thunderstorms covers other central North Island areas from Manawatu and Tararua District northwards.

These thunderstorms will be accompanied by heavy rain with intensities of 10-25 mm/h range, and with a low risk of localised downpours in excess of 25 mm/h.

However, for Waikato, Waitomo, Taumarunui, Taupo and the Bay of Plenty, there is a moderate risk of localised downpours of 25 to 40 mm/h.

If any downpours do occur, they could cause surface flooding and make driving conditions hazardous. A Severe Thunderstorm Watch for downpours is in force.

"Our Civil Defence team advises those camping and holidaying near waterways or in low lying areas to keep up to date on local conditions and be prepared to move to higher ground to avoid getting flooded out," says a Thames Coromandel District Council spokesperson.

"The rain band will pass quickly heralding a pleasant start to 2024 and five or six days of settled weather."

South Island

For the South Island, an upper cold pool will lead to increasing instability with thunderstorms and hail in some areas.

There is a moderate risk of thunderstorms this afternoon and evening about Canterbury south of Rakaia, Otago and inland Southland, and about the remainder of Canterbury in the evening and at night.

These thunderstorms will bring brief heavy rain of 10-25 mm/h, and hail mainly 10-20 mm diameter, however there is a low risk of larger damaging hail greater than 20 mm diameter.

A few of the thunderstorms about Canterbury may be also be squally with localised wind gusts of 100 km/h.

A low risk of thunderstorms covers many other South Island areas.