Winter blast set to continue today

State Highway 8 - one of many roads in the South Island to close. Photo / Supplied

Cold winds and heavy snow are continuing to blast New Zealand today.

Much colder air was expected to move onto southern New Zealand this afternoon, with snow lowering to near sea levels in Fiordland, MetService said.

Snow showers will lower to 300m in south Westland and should continue through to tomorrow in Southland and Clutha.

Snowfalls will continue to affect all the main alpine passes and also some roads in Southland and Otago.

"Motorists are advised to take extra care and check road conditions before travelling," Metservice said.

"With strong cold southwesterlies and snow showers forecast for Southland and Clutha tomorrow, farmers may wish to consider shelter for any vulnerable animals."

Skifields were likely to be closed for the rest of the week, MetService forecaster Oliver Druce told Radio New Zealand.

All fields were likely to receive large dumps for the next two days at least, he said.

Severe weather warnings have been issued for Westland, Fiordland, Otago, Southland, Manawatu, Wairarapa, and Wellington.

Heavy rain is now falling in the Tararua Ranges, MetService said, with 100-140mm expected between 9am and 9pm tonight.

Lightning strikes students

Yesterday's wild weather led to narrow escapes for two teenage boys believed to have been struck by lightning.

The two students from Canterbury's Christ's College were caught in an electrical storm while cycling between Little River and Motukarara near Christchurch.

The American exchange students from Tennessee jumped from their bikes and were found lying in the grass by fellow cyclist Kerren Flanagan, 31.

She was riding on the same track with a friend and passed the pair at a gate as the storm rolled in.

"There was massive thunder, massive lightning. It got really scary when the lightning was right in front of us," said Ms Flanagan.

"One of the lightning strikes went horizontally in front of my eyes - I was just freaking out ..."

When the weather forced Ms Flanagan and her friend to turn back, they found the bikes abandoned on the trail and the boys lying in the grass nearby.

"The two boys said they'd been hit ... One boy was hit in the hand but the other didn't know where he was hit. It might have just been his bike and he just felt it."

Ms Flanagan said the boy who said he was hit on the hand did not have any burn marks.

"We think it might have entered the bike and escaped out his handlebars because it just got his hand."

She stopped a passing van, and its driver took the students back to a car park where their host family picked them up and took them home.

Close call with tornado

In Northland, Jackie Winters was asleep about 1am when she was woken by her dog Luke running under her bed and what sounded like a plane flying outside her window.

Moments later she watched as her roof was torn off by a mini-tornado.

But Ms Winters, a Wellsford postie, counts herself lucky to be alive.

The tornado took half her roof, then travelled a further 75m through a nearby paddock before petering out.

"The wind just came like full throttle it sounded like a DC3, I could see the posts holding the verandah up on the deck rising up and down and the window was breathing.

"I said to the dog 'we'd better get up' so we were just getting out of bed and bang! the roof went."

Ms Winters and Luke were unhurt but shaken.

"It's not until after that you think "crikey, that was lucky," she said.

Weather Watch analyst Philip Duncan said further tornadoes were unlikely today but the bleak weather - fuelled by a strong and cold southwesterly windflow from the Southern Ocean - would continue bringing heavy showers and strong gusty winds to exposed places in western parts of the North Island.

Mr Duncan said the storm would peak today off the western coast of the North Island, and Taranaki would be the most exposed to fast-moving storms coming that could bring thunder and heavy downpours.

"They may get up to Auckland, but they are certainly going to be weakening once they head further north."

Mr Duncan said Auckland's weather would start to improve tomorrow and by Friday the frequent showers and wind were expected to dissipate.

"We are looking at hopefully sunny settled weather moving back in hopefully by early next week."

Bad day for flying

Strong winds hammering the lower North Island have also blown sea birds inland to areas where they are normally not seen.

"Storms are bringing in dozens and dozens of seabirds inland," said Department of Conservation biodiversity programme manager Peter Simpson.

DoC was asking for public help with the recovery effort.

"If people are keen to help, the best thing they can do for these birds is to put them in a box and return them to the water's edge as soon as they can," Mr Simpson said.

Piha Surf club general manager Tony Johnston last night said a "howling gale" had created huge waves.

He thought they were at least 6m but it was difficult to say.

Mr Johnston said he he'd seen higher waves before but yesterday's storm had created a "quite spectacular" scene of big surf.

Great weather for skiing

The storm which dumped about 20cm of snow on Arthurs Point, about 5km from Queenstown, early yesterday is expected to continue bringing snow to low lying areas for the rest of this week.

The snowfalls caused havoc on roads, closed schools and cancelled flights.

Last night, State Highway 94 between Te Anau and Milford Sound and State Highway 93 between Mataura and Clinton were closed by snow.

All schools in Queenstown were closed, but the nearby Arrowtown school stayed open, although school buses were not running.

Air New Zealand delayed an 8.45am flight from Queenstown to Christchurch for about an hour, diverted a flight bound from Christchurch to Queenstown and cancelled another flight from Christchurch to the resort. Flights from Queenstown to Wellington and Christchurch were also affected.

A Pacific Blue flight scheduled to arrive at 3.30pm from Sydney was diverted.

- additional reporting: OTAGO DAILY TIMES, NZPA