We hear it all the time. (and a lot more this past week) 

"It's minus 28, but it FEEELS like minus 40 out there!"

What even is 'windchill?' It is real? Does it matter? 

Is it some poor schmuck or intern that got sent outside to tell us how cold it's feeling??

In reality... that last one is kinda true.

I called up meteorologist with Environment Canada, Sara Hoffman to ask her what this whole windchill thing is about. 

“Wind Chill," says Sara, "Was a giant study some time ago that had many participants exposed to the cold and different levels of wind to create this index. This index gives us a ‘feels-like’ temperature that we can use to see how we are affected by the cold and strong wind in combination. Not just the cold.” 

...those poor, poor souls! (someone get them a nice hot cocoa STAT) 

So why do we need to know this? 

In perfectly still calm conditions, our bodies are able to warn the layer in contact with their skin. (this is called the boundary layer) We warm-up that surrounding layer of air to create insulation with the temperature. 

That is why when it starts to cool down, but there is no wind, we feel a bit warmer because our bodies are able to regulate that air in contact with us. 

When we have cooler temperatures in addition to the wind, that wind will blow that nice warm air away. 

“The more that boundary layer, in combination with our skin, can't help to insulate us it can feel a lot colder 'cause our bodies have to work harder to warm up that boundary layer.” She adds “So we often use the index of say minus 40 to try and describe an extremely cold or a colder feeling condition due to strong wind.”  

It's worth noting that 'windchill' doesn't have a unit like degrees.

Sara explains it better.

"Some would say, 'We have a wind chill of like minus 45 degrees.' That's inaccurate. You would just say we're at a wind chill of minus 45 and at a temperature of minus 38 degrees Celsius."

 Find more information on the Enviro-Can Website Here

~logan