The good; the bad; and the really windy

Wellington's wind is almost unfathomable to those who have not experienced it.
Wellington's wind is almost unfathomable to those who have not experienced it.

If you've given up on using umbrellas and wrap around items of clothing, chances are you're in Wellington.

Speak to any visitor or new resident about the capital's weather and the first thing they mention is the wind. And not usually in a good way.

Yet speak to the weather geeks out there, or the forecasters and climate scientists who choose to make Wellington their home, and the wind is (almost) always a feature to be embraced.

It might howl through the city's streets and make standing vertical a challenge from time to time, but it is also a quirk that undoubtedly sets us aside from other capitals.

MetService spokesman Daniel Corbett, who moved to the city in the middle of 2011, sums up the most striking feature of the weather he has encountered here as "the funnel effect - that's Wellington's weather in a nutshell".

Chicago might be known as the "windy city", but he says Wellington is undoubtedly windier than the American city - and probably any other capital.

"It's purely because of its positioning, where New Zealand sits between the tropics and the poles, and the orientation of the land. Air has to go up around it."

The result is a city buffeted by predominantly northerlies or southerlies and residents who cannot help but notice what the weather is doing.

"We're so surrounded by weather you get to appreciate it because you feel it. When a weather system is coming, you certainly feel it."

While gusts in the city regularly top 100kmh, many pedestrians will argue that walking along Featherston St will lead you to experience the full brunt of our most famous weather feature.

In 2011, scientists from Niwa, GNS Science and Auckland University embarked upon a study into just how windy Wellington could get as the wind was funnelled through features of the city's natural landscape.

As the study got under way, Niwa principal scientist Mike Revell said wind tunnels around the city created a "speed up effect", causing gusts to be two or three times those felt in other areas.

He says wind funnelled through the Cook Strait contributes to Wellington's weather, but the wind around any of the city's peaks, such as Mt Victoria, Makara or Tinakori Hill, can get up to three times greater than the wind surrounding it because of the land's features.

Motorists along the Rimutaka Hill Rd will also know the wind can magnify up on its summit, while Mt Kauaku is often one of Wellington's windiest spots.

But at the extreme end, Wellington's wind is almost unfathomable to those who have not experienced it. The windiest day on record was April 10, 1968, when a speed of 267kmh was recorded at Otaranga Bay where the Cook Strait Cable comes ashore. It was the day of the Wahine disaster.

Dr Renwick says the gap in the North and South Island mountains, plus the effect of winds pushing through the Fouveaux and Cook Strait, make Wellington particularly windy.

Yet on the less violent side, the capital's average temperature over the course of a year hovers around a temperate 13degC - and we also get an average of about 1950 hours a year of sunshine to bask under.

Dr Renwick says Wellington's highest maximum temperature was 30.6C, recorded at Wellington Airport on Feburary 10, 1982. But such balmy highs are rare and rely on warm air blowing over the North Island to Wellington. "Everything has to be lined up. It's a rare event."

Another rare event is snow to sea level, which brought the capital to a standstill in August 2011. The coldest maximum temperature during that event was around that of the lowest ever recorded, 4.5degC in 1938.

Dr Renwick also believes that if you are going to be in Wellington, you have to embrace the weather - wind, rain, sun, and of course storms.

"Wellington is a very elemental place. You can get extreme weather and sea conditions and you really are confronted by the elements. You have to be comfortable with that."

The Dominion Post