We have an unsettled Sunday developing across New Zealand with wind and rain and some isolated severe weather potential too. It’s being caused by a new low that is rapidly forming east of the country and a large high that is building west of the country. This “squash zone” is allowing a very strong and much colder than normal air flow up over NZ for Sunday and easing Monday.

NORTH ISLAND:
Showers for the upper half of the island today with driest weather in Northland, Auckland, eastern Coromandel Peninsula, Bay of Plenty, Wakato and Gisborne. Rain more likely in the southern half of the island with some heavy falls, especially around Wairarapa and the Tararua and Hawke’s Bay ranges later, pulled in by strong SE winds. Westerlies for northern NZ to start with but by the end of today most, if not all, will have windy S to SE winds. Gales, possibly damaging, most likely around Cook Strait and exposed areas nearby later today or overnight tonight. Becoming cooler, may not be until later for some in the north.
HIGHS: 16 to 22

SOUTH ISLAND:
Rain in the north east, mostly in the top half of the island with heavy falls around Kaikoura and surrounding ranges to Cook Strait. Lighter drizzly rain towards coastal Otago or showers with dry spells. Dry on the western side of the island and mainly dry in Southland. There is good news – some rain may be falling in Nelson today. Much cooler than normal for most.
HIGHS: 10 to 18

– WeatherWatch.co.nz