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Wind Chill: A Definition

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What Is Wind Chill?
wind chill factor definition what is it montreal canada environment weather winter

Is "wind chill" another way of saying "warm and cold, comforting yet stoic, gentle yet unfeeling"?

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Wind Chill Factor: What is Wind Chill and Should I Be Concerned
On a particularly frigid January day in Montreal, I asked Norbert*, a hot Singaporean cop studying English literature in his free time, a gentleman who happens to be one of my best friends in the whole wide world, what “wind chill” means to him.

Here’s what Norbert had to say as he was enjoying an evening out with friends, taking in the humid 25°C (77°F) ambiance at home:

“Wind : a gentle summer’s breeze, warmth, comforting, silent strength.
Chill: cold, bitter, frozen...
Wind chill: warm and cold, comforting yet stoic, gentle yet unfeeling.”

Representing the most romantic view I’ve heard on the topic, note that Norbert has never been to Montreal. Or Canada. In the winter.

Environment Canada’s weather experts propose a different take on the subject, defining wind chill as “chill that results from a specific combination of wind speed and air temperature, expressed by the loss of body heat in watts per square metre (of skin).”

As for wind chill index, it’s an index “used to determine the relative discomfort resulting from a specific combination of wind speed and air temperature, expressed by the loss of body heat in watts per square metre (of skin).”

In other words, there are winter days when it’s windy. And when it’s windy, it feels colder if skin is exposed.

So if a local weather report says it’s currently -10°C (14°F), and -20°C (-4°F) with the wind chill, that means it only feels like -20°C to unprotected skin, which leads to faster body heat loss, again, because of the wind. But to an outdoor bench, -10°C is -10°C: for inanimate objects such as cars or rocks, wind chill is irrelevant.

Ways to prevent the heightened sensation of cold and consequentially faster body heat loss? Bundle up. Cover up as much skin as possible with gloves, mittens, scarves, hats, tuques, earmuffs ... whatever it takes. And keep outdoor exposure as minimal as possible if wind chill reaches -28°C to -40°C (-18.4°C to -40°F), when exposed skin can freeze in as little as 10 to 30 minutes.

*Norbert is a fictional name.

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