Readers’ response: How is the wind chill factor calculated? | Meteorology


On the weather forecast, we always say: “With the wind, it will be like …” How is the wind chill factor calculated? Mick Rawlinson, Brighton

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Readers respond

My dad refuses to believe in the wind chill factor because he didn’t have it in his day. salamandretome

The perceived and actual temperature difference is the result of a complex mixture of air temperature, relative humidity and wind speed, as well as differences in health, genetics, hydration, body shape, dress code and metabolism. So, wind chill temperature is fully and highly subjective, not an exact science. Weather services in different countries make many assumptions about their particular region and population, so their estimates may differ from those provided by local weather services in other regions. Did you feed the fish

Wind chill = 13.12 + 0.6215T – 11.37 (V0.16) + 0.3965T (V0.16)

T = Temperature in degrees Celsius
V = Wind speed in kilometers per hour

Alternatively, it can be measured in brass monkeys. Today it is four. woodworm20

Multiply the wind speed by 0.7. Then subtract this value from the air temperature. So in Bodalla, NSW, on December 1, the first day of summer, with a wind speed of 7 km and an air temperature of 25 ° C, the cooling factor is 20.1. Not too cold at all. Ursula Nixon, Bodalla. NSW, Australia

There is a common misconception that wind chill lowers the temperature. This is not the case. The ambient temperature can never drop below the reading of the still air thermometer. The wind simply serves to accelerate the rate at which exposed skin falls to that level. Thus, a strong wind at 0C produces a net rate of body heat loss equivalent to that on a calm day of about -10C.

As long as you keep your skin covered (hat, gloves, good windproof top layer), wind chill does not affect you. For this reason, I climbed a Scottish mountain 10 days ago in side rain and winds 45-50mph (force 8-9) in two base coats and a thin mid coat, as well as a good waterproof top. Room temperature 5C, “smells like” -5C, but I didn’t notice. Even at rest at the leeward summit. Rickytip

If your nuts and bolts are freezing, it’s cold. Mystickitty

Frankly, if it’s cold enough to freeze the wicks of a brass canoe, it’s cold. javathedog

It’s the same answer every time, which makes it easier.

“According to the car, it’s 3C – and with the wind chill factor, it’s fucking freezing.

“Apparently it will be -1C tomorrow, and with the wind chill factor it will be fucking freezing.” “

Etc. I don’t care anymore

I imagine that the “wind chill effect” directly depends on the ability of any individual body to warm the affected body area. As far as I know, this can really only be done by circulating warm blood to the affected area. So, a person with an exposed area who is suffering from arthritic disease will most likely experience a wind chill much more than a person without any risk to their health. It is really about “cooling” the core body heat and the difficulties of restoring protection. Surface cooling can be protected against. The real problem is when it gets in and becomes hard to fix by default. NewMe359

I remember being surprised to find that, even indoors, the air temperature isn’t the only thing that affects the “warmth” of a room, from a human perspective. Heat leaves the body by radiation as well as by contact with air; cold walls or ceilings can increase this rate of loss, and make a noticeable difference in “heat”, even if a thermostat keeps the air temperature constant. Really sophisticated thermostats sometimes even measure outside temperatures and increase or decrease the indoor air temperature setting to compensate for this effect. Filter reader

How to calculate wind chill with an explanation can be found here.

The wind chill factor was designed for a limited purpose. It measures heat loss from exposed areas of the human body, such as hands and face, at low temperatures and at measured wind speed. With this information, people venturing outside in unusually freezing weather would experience an approximate delay before exposed areas of the body succumb to frostbite. BijiDog

Not being good at numbers but being a resident of Canada, when I hear that the wind chill is making the temperature considerably colder outside, I remember wearing a hooded coat, a woolen scarf and sweaters. gloves or mittens suitable, to say nothing of comfort boots with good traction. I also wear a beard, an extra adornment that also helps prevent frostbite. Richard Orlando, Westmount, Quebec


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