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WEDNESDAY FEBRUARY 14 - WIND CHILL QUIZ
I thought I'd start tonight with a little quiz, appropriate for this time of year.
Let's say you set a gallon of water outside in a plastic jug. The air temperature
is 35oF, but the wind is blowing at 25 mph, so the wind chill is
about 10oF. How
long will it take the water to freeze? Is that your
You are correct (I'm giving you the benefit of the doubt) - the water will
NOT freeze, because the air temperature of 35oF is above freezing, and that's
all that matters. The wind chill has nothing to do with it - wind chill is
only relevant for living things like humans and animals that maintain their
temperatures well above the temperature of the air. I've also heard commercials
in which antifreeze companies brag that their product will protect your
radiator down to a wind chill of something like -60oF. Here again, the
wind chill is irrelevant. The only temperature the fluid in your cooling
system has to worry about is the air temperature, not the wind chill.
By the way, recent research has shown that many of the
current wind chill
values are probably too low, in most cases by 5-10oF. So there's
a chance that an official revision of the wind chill formula will come out
sometime in the next year or two.