Gales up to 100km/h set to lash North Island

Gales of up to 100km/h are set to lash the North Island this weekend after a brief respite from this week's heavy rain and gales.

Both main forecasters are warning a deepening low will bring strong winds to the central North Island and upper South Island from tomorrow afternoon.

The windy weekend weather comes after a storm moved across the North Island midweek, causing slips and bringing down trees and powerlines.

The weekend low would also being spells of rain to the North Island at times, with heavy rain in parts of the West Coast of the South Island.

But there is also some good news, with westerly and northerly winds likely to push temperatures well into the mid to upper teens in the afternoons.

The MetService said gales were likely to be worst in Hawkes Bay, Wairarapa, Manawatu and Marlborough, with gales of 50km/h, gusting to twice that speed, in Hawkes Bay and Wairarapa.

The wind would also pick up further north in Bay of Plenty and Auckland, but it was unlikely to be as strong. Auckland could expect gales of 40km/h, with gusts of up to 60km/h in exposed places.

MetService duty forecaster Leigh Matheson said Auckland would get some fairly strong westerlies, but they would not be of gale force.

Gales could be severe for a time in central Hawkes Bay and northern Wairarapa, where the wind would hit from tomorrow afternoon through to tomorrow evening.

"Basically what's happening is there's a fairly active low that's deepened off Tasmania, and it's heading towards us now. There's quite a good band of rain coming on to the West Coast, but it's fairly weak as it comes onto the North Island.

"The low itself crosses over on Saturday and it's really with that that we see the strong westerly winds that come across the upper South Island into the lower North Island."

The low will also bring showers to Northland, Auckland, Wellington and the east, from Gisborne to Wairarapa, on Saturday.

On Sunday, there will be isolated showers turning to rain in the evening, especially in the west.

In the South Island, the MetService has issued a heavy rain warning for Westland, Buller and Canterbury from today through tomorrow.

The heaviest rain was expected to fall in the Southern Alps, which would get up to 160mm in 24 hours.

WeatherWatch analyst Aaron Wilkinson said a low over Stewart Island and a high northwest of the country would push together on Saturday to make a "squash zone" around central New Zealand, where winds would be strongest.

He said northerlies were likely to reach gale force around Wellington and surrounds, with winds of more than 100km/h on exposed hilltops and some highways.

From tomorrow evening, the warm, windy weather would move further north to Hawkes Bay and Gisborne. Winds would also build in Bay of Plenty and Auckland, with blustery conditions expected in parts of Taranaki.

"Winds will ease on Sunday but could return again later on Monday for Northland," Mr Wilkinson said.

Late September through to early November tended to be New Zealand's windiest months, which was very normal for the middle of spring.