It's expected to clear away in the afternoon with most wet weather sliding up to Cook Strait and the lower North Island. Inland areas could have a cold start with highs in the south between 10C and 16C.
Monday could take a turn for the worse in the lower South Island, as an active front moves north. It will hit the North Island on Tuesday and weaken, MetService said.
A heavy rain watch is in place for Fiordland from 9pm today until 5am Monday, and a strong wind watch is in place for Southland and Clutha overnight.
There is also moderate confidence of heavy spillover rain into the Otago and Canterbury headwaters on Monday, MetService said.
Today's weather
Whangārei
A fine start, but showers developing afternoon, chance heavy, then clearing at night. Northwest breezes. High 17C, Low 8C
Auckland
Mostly fine, but a few showers, mainly afternoon. Northwesterlies dying out evening. High 16C, Low 8C
Hamilton
Cloudy periods and chance shower or two. Westerly breezes. High 16C, Low 5C
Tauranga
Remaining showers clearing morning and becoming fine. Westerly breezes. High 17C, Low 7C
New Plymouth
Cloudy periods. A few showers, mainly in the morning. Westerlies. High 15C, Low 8C
Napier
Becoming fine in the morning. Northwesterlies. High 19C, Low 5C
Whanganui
Morning showers, then becoming fine in the afternoon. Northwesterlies. High 16C, Low 8C
Wellington
Occasional rain clearing in the afternoon. Northwesterlies, strong at times. High 13C, Low 9C
Nelson
Morning cloud and a few spots of rain, then fine. Southwest breezes. High 15C, LOw 7C
Christchurch
Morning rain, then becoming fine. Southwesterlies tending northerly afternoon. High 13C, Low 3C
Dunedin
Mainly fine, but possible inland fog early morning. Southwesterlies tending northeast afternoon. High 13C, Low 7C