Gale winds of up to 150km/h could hammer some parts of northern Wairarapa today.
Chris Noble, MetService severe weather forecaster, said a front was expected to have moved over much of the South Island last night before sweeping quickly across the North Island this morning.
He said heavy rain in the west and strong or gale northwesterlies were expected in eastern areas ahead of the front, and westerly gales were predicted to hit northern Wairarapa today in the wake of the fast-moving weather system.
Northwesterly gales were expected to be severe in exposed places in Wairarapa last night, he said, with gusts reaching up to 130km/h.
Mr Noble said gusts could reach up to 150km/h in more elevated Wairarapa locations, including the Rimutaka summit and Castlepoint beach.
He said the high winds "could damage trees and powerlines and make driving hazardous", but were expected to ease in southern Wairarapa and Wellington from about 6am this morning.
However, westerly gales behind the front could still be severe through to tonight in northern Wairarapa and central Hawkes Bay, he said.
The highest wind speeds recorded at Castlepoint over the past two months included gusts of 137 km/h and 139 km/h on October 5 and September 7 respectively, according to MetService data.
The highest wind speeds recorded on the Rimutaka Summit over the same period included gusts of 122 km/h and 172 km/h on October 5 and September 8 respectively.
Chief forecaster Peter Kreft said the strong westerly weather pattern is expected "to blow itself out" over Labour Weekend.
"The holiday weekend should get off to an unsettled start, with wet and windy weather finding its way into many places on Saturday as a trough rattles across the country," Mr Kreft said. "However, things should settle right down for most during Sunday, as the strong westerlies gradually leave us."
Mr Kreft said Monday is expected to be dry for most areas.