February shapes as driest ever despite rain

It may feel like the worst summer for a long time, but some areas of New Zealand - in cluding Wanaka - are on track to have their driest February on record.

But yesterday, the North Island was far from dry, with flash-flooding following heavy downpours.

Torrential rain and thunderstorms battered Northland, and Auckland motorists battled atrocious driving conditions as a frontal band of rain made its way very slowly across the top half of the North Island.

Because of its very slow movement, coupled with the heat and high humidity, the front continued to grow, with the bulk of the torrential downpours falling on the Coromandel Peninsula and Bay of Plenty.

A Fire Service spokesman said that throughout the day, staff were called to spots of flash flooding in Rotorua, Titirangi and at Northland Timber Joinery in Maungaturoto.

He said there were also a few fender-bender crashes around Auckland because of the weather.

WeatherWatch said the weather created atrocious driving conditions, with near-zero visibility in rain and torrential downpours creating surface flooding. In Mt Roskill, an enormous branch snapped off a tree yesterday, crushing the outdoor play area of a childcare centre.

Luckily the branch fell in the early hours of the morning when the Peterpan Childcare Centre was closed.

But yesterday was one of very few wet days during February.

National Institute of Water and Atmospheric Research climate scientist Georgina Griffiths said the lower two-thirds of the South Island had seen 20 per cent less of its average rainfall during the first 21 days of the month.

"So they've not even had a quarter of rain for what's typical down there,'' Ms Griffiths said.

"It's been really dry over New Zealand to date, believe it or not.''

Wanaka, Milford Sound, Waiouru and Kerikeri had so far had the driest February yet, "but those numbers could change because there is going to be some more rain''.

But dry weather did not mean it was warmer than usual - much of the North Island experienced lower-than-average temperatures.

At this time of year, Hamilton would normally be sitting around 24C but its average this month was 22.4C, Gisborne was 2.5C below average at 22C and Christchurch was 2C below its norm, with an average of 20C.

Ms Griffiths said February had lacked northwesterly winds and was cloudier than usual, which led people to believe it was raining more often than it actually was.

But the cloud and muggy air are on their way out, for now, as a westerly change overnight brought in a relief of fresh air.

WeatherWatch chief analyst Philip Duncan said the country would be swept with a strengthening southwest flow today, which would help to lower the humidity.

A high moving in from the Tasman should settle conditions down over Sunday and Monday.

additional reporting: Morgan Tait