WELLINGTON - Gusting southerly which destroyed property, left commuters stranded and cut power to Wellington residents last night has moved north but fresh gales are expected in the lower South Island from today.

High winds blew over trees and powerlines and swamped emergency services in Wellington and Kaikoura as atrocious weather shunted up the east coast in the afternoon.

Several people received minor injuries, including a teenage boy hit by a falling tree branch at Rarangi near Blenheim.

Wind gusts of nearly 150km/h were recorded on Wellington's Mt Kaukau, and the temperature dropped from 19.9C to 9C when the "aggressive" southerly front reached the capital late in the afternoon, weather analyst Philip Duncan said.

Winds gusted over 120km/h elsewhere in the city, causing damage to roofs and powerlines, and bringing hail.

Power was cut to thousands of households around Wellington after lines were blown down from Island Bay to Upper Hutt, a Wellington Electricity spokesman said.

The Kapiti Coast and Wairarapa were also affected by power cuts.

Trees were down across roads last night, but the only road completely blocked was Paekakariki Hill Rd.

Train services were disrupted for several hours after falling trees damaged overhead powerlines.

Trains resumed on the Hutt Valley and Wairarapa lines by 7.30pm, with full service resuming by 9.30pm, KiwiRail's rail passenger manager Ross Hayward said.

Flights in and out of Wellington Airport were delayed but Interislander sailings were not affected by the weather.

A woman was trapped in Carterton when a tree fell down across her car, causing minor injuries.

A police launch was called out to rescue a kayaker about 4.30pm in Wellington's Oriental Bay, but after several hours' searching it appeared to have been a yellow racing buoy, police said. There had been no reports of an overdue kayaker.

Conditions on the harbour were described as "atrocious" by the Wellington Coastguard, which was helping police.

The weather also caught out yachts taking part in an annual fundraising race by the Royal Port Nicholson Yacht Club. Eighty-two business people were racing around Somes Island and back on members' boats.

Thirteen keel boats took part, with three needing to be towed to shore and three having to wait out the storm, yacht club chief executive Dean Stanley told NZPA.

One person fell overboard but was quickly rescued, and another was taken to hospital.

Roofs were also blown off buildings at St Bernard's College in Lower Hutt and Samuel Marsden College in the Wellington suburb of Karori, which was hit by a mini tornado.

Earlier, the wild weather hit Kaikoura, between Christchurch and Picton, where southerlies gusted to 115km/h and the temperature plunged to 7C.

A 15-year-old boy hit by a tree near Blenheim was flown to Wairau Hospital with lower leg and suspected spinal injuries, a Summit Rescue helicopter pilot said.

The front had moved north overnight, but parts of the Clutha and Dunedin regions were preparing for another gale, expected to hit over the weekend.

The MetService issued a severe weather watch for the regions last night.

Forecaster Heath Gullery said wind gusts could reach 100km/h, possibly more at times, from about dawn today until dawn Monday, especially near coastal hills and headlands.

The winds could damage trees, powerlines and roofs, he warned.