Rain and showers scattered over the country today are forecast to remain for the week, and get even stronger over the weekend.
MetService meteorologist Arno Dyason said today there were a few showers scattered across the North Island, while heavy rain and potential thunderstorms peppered Westland and Fiordland.
The heavy rain was coming in a front embedded in a north to northwest flow moving across the country.
Another front was forecast to move on to the west of the South Island tomorrow, bringing more heavy rain to Westland, Buller and northwest Nelson.
This front was forecast to stall over the northeast of the North Island on Friday, and remain slow-moving there through the weekend.
The upper North Island was in for a wet weekend, Dyason said.
"Anywhere that is exposed to the northeast is in for a wet weekend, including Northland, Auckland, Bay of Plenty and around to Gisborne."
Another low could develop on this front to the northeast of New Zealand on Friday, but it was still uncertain exactly where it would end up, and where the heaviest rain would be.
There was potential for heavy rain about Coromandel Peninsula, Bay of Plenty and Gisborne, especially about the ranges, during Friday, Saturday and Sunday.
Strong to gale force easterly winds were also possible over parts of the North Island to the south of this front and possible low, but at this stage gales were unlikely to be severe.
Meanwhile, a weak ridge of high pressure would cover the South Island bringing fine weather from Friday through Sunday.
Fine spells and a few showers. Light winds. 18C high, 7C overnight.
Cloudy periods, a few showers. Southwesterlies. 16C high, 7C overnight.
Fine spells and a few showers. Light winds. 16C high, 5C overnight.
A few showers. Northerlies dying in the evening. 16C high, 8C overnight.
New Plymouth Fine spells, chance shower. Northwesterlies. 15C high, 8C overnight.
Napier A few spots of early morning rain, then long fine spells. Northwesterlies. 18C high, 5C overnight.
Wellington A few morning showers, then becoming fine. Northerlies. 14C high, 10C overnight.
Nelson Fine. Northerly breezes. 14C high, 4C overnight.