Severe weather warnings have been issued for later this afternoon as a "particularly active" front moves in, bringing gale-force winds and heavy rain to two thirds of the country.
The South Island was expected to bear the brunt of the foul weather as the low passed over late this afternoon, and the north as far as Taranaki could expect rain from tomorrow.
MetService forecaster Daniel Corbett said from mid-afternoon, severe wind gusts would build, but would ease in Wellington and the Wairarapa during the evening.
Gusts of up to 130kmh were expected in some places in the Wairarapa.
Rain coming up from the South Island was briefly expected to become heavy over parts of the North Island tomorrow evening and Sunday morning, with a low risk rain could build to reach warning levels around Mt Taranaki, the central North Island high country and the Tararua Ranges tomorrow night and Sunday morning.
Saturday's rough weather was part of a wet northwesterly strengthening ahead of a trough over the Tasman Sea, which was forecast to bring a burst of heavy rain to the west of the South Island, then spill over into the headwaters of Otago and Canterbury's rivers and lakes.
MetService warned there would be unusually high rainfall to the east of the Southern Alps. People were advised to take extreme caution as rivers and lakes were likely to rise rapidly bringing possible surface flooding and slips.
Corbett said the weather would hold steady for the third All Blacks v Ireland test match in Hamilton tomorrow night.
Last week's game saw the teams battle temperatures as low as -4 while playing in Christchurch.
Corbett said the crowds in Hamilton would be much more comfortable as light showers early on should clear up in time for the game and the temperature should be significantly higher than what was felt in Christchurch.
Further north around Auckland and Northland, temperatures were expected to stay above 15 degrees, with some northwesterlies and only a small chance of showers. Those areas could get rain on Sunday, however.
Hawke's Bay was expected to gain some of the nation's highs this week, with winds pushing the temperatures to above 14 degrees, keeping it dry and blustery with high cloud arriving towards the afternoon.
From early next week conditions were expected to improve again with mild temperatures and generally calm weather.