Wellington: the world's windiest capital is a windsurfing mecca | Photo: RPNYC

Wellington is the world's windiest city. Let's find out how windy the capital of New Zealand can be.

To put things into perspective, in the United States, any urban area with an average wind speed of more than 7 knots (12.9 km/h) is considered a windy city.

Take Chicago, for example. America's Windy City has an average wind speed of 8.9 knots (16.6 km/h). But Wellington tops that with an impressive annual mean wind speed of 11.8 knots (22 km/h).

The Kiwi capital is, in fact, extremely windy. It's not just reputation. In some days, especially in October, you might have problems walking on the street. And yes, in Wellington, opening an umbrella shop could be the worst business idea ever.

During October, the city has a spectacular mean of 27 days with wind speeds over 15 knots, 19 of which are over 20 knots. North is the prevailing wind direction in Wellington.

So, the capital city of New Zealand is the windiest metropolitan region of the world. However, Wellington is not the windiest place on Planet Earth.

The Guinness World Record belongs to Commonwealth Bay, in Antarctica, with an average annual wind speed of 43.1 knots (80 km/h). The strongest wind gust ever - 220 knots (407.44 km/h) - was recorded on Barrow Island, Australia.

Wellington: Blown Away

But why is Wellington so windy? The world's wind capital is located in the Roaring Forties region - between the latitudes of 40 and 50 degrees - where gale-force westerly winds often travel.

When they pass South Australia, they are channeled through the Cook Strait, between New Zealand's North and South Islands, and hit Wellington at full speed after being squeezed by the nearby mountains.

So if you're a speed windsurfer or a kiteboarder, Wellington is the place to be. Just make sure you pick the right sail and kite.

If you need more real-time data on the windiest spots on the planet, check the wind map of the world.

Wellington | Wind Facts & Figures

233: the number of days winds reached gale-force speed (33.4 knots, 62km/h) in Wellington's windiest year
173: the number of days a year with wind gusts greater than 32.3 knots (60 km/h)
133.9 knots (248 km/h): the highest wind gust ever recorded in Wellington (Hawkins Hill)
63.01 knots (116.7 km/h): the highest wind gust ever at Wellington International Airport
37 percent of all Wellington wind blows from the north
22 days per year with mean wind speed over 40 knots (63 km/h)
15.6 knots (29 km/h): the average wind speed at the Wellington International Airport