Issued 10:00 am Saturday, 3 January
A slow-moving low is crossing the upper North Island today. It brings rain and a high risk of thunderstorms. Conditions improve from the west and south overnight as a ridge builds. Today and this evening remain hazardous, especially for boaties.
Upper North Island
From Northland south to Waitomo, Taupō and the Bay of Plenty, showers are developing. Some turn heavy and thundery this afternoon and evening. Severe storms are already firing in parts of Auckland and Waikato. Expect short bursts of torrential rain, localised surface flooding, and sharp drops in visibility. Conditions ease overnight. Tomorrow looks partly cloudy with a few afternoon showers.
Gisborne and Hawke’s Bay carry the main risk. The rain is heavy at times. Thunderstorms remain possible through to early Sunday. Warnings stay in place, and the ranges are likely to take the biggest totals. Watch for fast rising streams, slips, and difficult driving.
Central and lower North Island
From Taranaki to Wellington, including Taihape and Wairarapa, it stays cloudy with scattered showers. Taranaki may see heavier downpours and a rumble of thunder this afternoon. The west clears this evening. Most areas turn mainly fine overnight and through Sunday.
Along the Wellington coast, strong southerlies will kick up a rough sea today, especially on the south coast and through Palliser Bay. Winds ease on Sunday, and the sea state settles through the day.
South Island
Nelson and Buller through to Fiordland look mainly fine today, with inland showers. Nelson may see a heavier burst and the odd clap of thunder. Tomorrow turns more cloudy with a few isolated showers.
Elsewhere, the South Island stays mostly cloudy. Isolated showers clear for a time today, then return to Southland and Otago tomorrow afternoon as a weak front moves through.
Chatham Islands
Cloudy with light showers today, clearing tomorrow morning.
Coastal and boating outlook
A ridge builds over the South Island today while the low moves east of the North Island. High pressure spreads north tomorrow and settles over many areas. A front approaches Fiordland late Tuesday, then weakens as it crosses the South Island on Wednesday.
Severe thunderstorm warnings and watches cover large parts of the North Island this afternoon and evening. Boaties should stay off the water in warned areas. If you are already out, head for shelter early. Keep clear of exposed headlands, river mouths, and bars.
