Most areas will take a little while to warm up after a relatively chilly night.
Auckland dropped as low as 7C in Albany, but will heat up for a relatively fine day and a high of 18C.
Similar weather is on the cards for much of the rest of the North Island, with only Wellington in for a tough time with some gusty northerlies.
Westerlies affecting the North Island and the western South Island!
The current state of New Zealand can be seen in the...
Posted by MetService New Zealand on Wednesday, 16 May 2018
Out east Gisborne and Napier continue their fine runs, with sunny conditions, warm northwesterlies and highs of 20C forecast. Much of the same is forecast there over the next several days too.
It will take the South Island even longer to warm up this morning after a freezing night for some.
Ashburton was the coolest at 0.6C, and Dunedin and Oamaru both hit a frigid 1.7C.
The east coast will warm for a relatively fine day though, with temperatures in the mid teens.
Later today a band of rain stretches up the country's west coast, Zachar said.
"From Fiordland to Northland we can expect at least a few showers today," Zachar said.
The heaviest rain is expected on the South Island's west coast, with a weather watch in place for Buller to 1am tomorrow.
The Tararua Range north of Wellington could also see some heavy rain through to 3pm tomorrow.
From tomorrow the "unsettled" period sets in, with no signs of slowing down.
"We are entering a very active weather pattern," Zachar said.
A series of fast moving fronts are expected to bring periods of heavy rain to the west and strong west to northwest winds to southern and eastern areas.
The rain tonight and tomorrow is coming from a slow-moving front sitting over central New Zealand.
It is forecast to move slowly north on Saturday morning, bringing rain to the upper North Island, especially around Auckland, Rotorua and Taupō.
It should clear quickly overnight Saturday, but on Sunday another front moves on to the country bringing decent amounts of rain to western areas.
Another active front is forecast on Tuesday, but will weaken as it moves north.
On Wednesday an even larger southerly front is due to move on to New Zealand, dropping temperatures even further, Zachar said.
Today's weather
• Whangārei
Long sunny spells, but one or two early showers. Southwest turning light northwest evening. 19C high, 10C overnight.
• Auckland
Mainly fine, apart from isolated showers, clearing early afternoon. Southwest turning light northwest evening. 18C high, 12C overnight.
• Hamilton
Cloudy periods with one or two showers. Westerly breezes. 17C high, 9C overnight.
• Tauranga
Some cloud morning and night, otherwise fine. Westerlies. 18C high, 11C overnight.
• New Plymouth
Cloudy periods with a few showers. Westerlies turning stronger northwest in the evening. 17C high, 13C overnight.
• Napier
Fine apart from some high cloud. Northwesterlies. 20C high, 11C overnight.
• Wellington
Fine with high cloud. A few showers at night. Gusty northerlies, strong in exposed places. 15C high, 12C overnight.
• Nelson
Cloud increasing afternoon with chance shower, then evening rain. Northerly breezes.16C high 9C overnight.
• Christchurch
Fine with high cloud. Northeast breezes. 16C high, 3C overnight.
• Dunedin
Fine with high cloud. Westerly breezes. 13C high, 6C overnight.
