Knowing the wind chill is in fact an essential part of Canada’s weather forecasts, as it provides everyone with the knowledge they need in order to stay safe in our worst weather.
I remember am radio reporting windchills like this, when I was a child. “Today’s high is -26C with a windchill of 2200. This means frostbite in three minutes on exposed skin, so bundle up!” And my parents had a chart that converted windchill values to frostbite times.
Going further back, I remember when that watts per square metre (the 2200 in your weather report) was introduced as a replacement for whatever windchill calculations they were using before.
One thing many people I know get wrong about windchill is the effect on needing to plug in a vehicle’s block heater. If you normally are good down to -20C on a calm day, you’ll also be good down to -20C on a windy day, despite windchill being far below -20. The engine will cool faster, not farther.
No matter how fast the engine cools off, it still won’t get any colder than the actual air temperature. Of course, that also means that if you are good for 4 hours at -20C on a calm day, starting with a hot engine, then adding wind means you might only be good for 2-3 hours.
Glad you understand this, I feel validated. lol. I had an argument with my coworkers about this in the mid 90s. They said overnight -10 or like -30 with windchill so they were covering their engines with blankets. (No block heater) I tried to explain their cold engine is not producing heat, so -10 is all the engine will “Feel”, and the wind will not make the engine -30.
Yeah, the wind can never chill something below ambient temperature. It can only pull heat from the warmer object to the cooler object. If both are the same temperature, then there’s no transfer of heat. More wind only makes the transfer happen more quickly.
I remember am radio reporting windchills like this, when I was a child. “Today’s high is -26C with a windchill of 2200. This means frostbite in three minutes on exposed skin, so bundle up!” And my parents had a chart that converted windchill values to frostbite times.
Going further back, I remember when that watts per square metre (the 2200 in your weather report) was introduced as a replacement for whatever windchill calculations they were using before.
One thing many people I know get wrong about windchill is the effect on needing to plug in a vehicle’s block heater. If you normally are good down to -20C on a calm day, you’ll also be good down to -20C on a windy day, despite windchill being far below -20. The engine will cool faster, not farther.
No matter how fast the engine cools off, it still won’t get any colder than the actual air temperature. Of course, that also means that if you are good for 4 hours at -20C on a calm day, starting with a hot engine, then adding wind means you might only be good for 2-3 hours.
Glad you understand this, I feel validated. lol. I had an argument with my coworkers about this in the mid 90s. They said overnight -10 or like -30 with windchill so they were covering their engines with blankets. (No block heater) I tried to explain their cold engine is not producing heat, so -10 is all the engine will “Feel”, and the wind will not make the engine -30.
Yeah, the wind can never chill something below ambient temperature. It can only pull heat from the warmer object to the cooler object. If both are the same temperature, then there’s no transfer of heat. More wind only makes the transfer happen more quickly.