Even though, years ago, we all knew that it felt colder on windy winter days than on calm ones and that the cold could cause frostbite more quickly when a 20 mph breeze was added to sub-zero temperatures, we didn't hear much about windchill factors when we read or listened to the daily weather report. We heard the actual temperature and knew to add some extra covering when the wind made our faces sting.

Now, of course, with a lean toward sensationalism in the news, actual temperatures are mentioned in passing and a big deal is made of wind chill factors -- I expect because it can make a mediocre winter day into a sensationally cold and dangerous day. But the weather prognosticators are not necessarily telling the whole story about wind chill factors and their impact.

Hearing of dangerous wind chills, I got to wondering how the calculations worked and what factors were used in those calculations. To get the full impact, would I have to run out of the shower naked and stand outside in the wind and see how fast my skin begins to freeze?

Well, a visit to the National Weather Service website offers a wind chill chart and even a calculator where actual temperature can be entered in one box and wind speed in another, with a resulting wind chill temperature popping up in a third.

But what was more interesting is how wind chill is calculated. The following factors are used in the index calculations:

• Wind speed at 5 feet (the average height of a human face when a person is standing out in the cold) with those wind speeds calculated from readings taken at the national standard height of 33 feet (the typical height of an anemometer);

• Based on a human face model;

• Incorporates heat-transfer theory, which is heat loss from the body to its surroundings on cold and windy/breezy days (saying nothing about going out in the cold when you've exited your shower and are dripping wet);

• Lowers the calm wind threshold to 3 mph;

• Uses a consistent standard for skin tissue resistance; and

• Assumes no impact from the sun (conditions such as under a clear night sky).

Yes, it sounds like quite a few factors and maybe a complicated mathematical formula requiring some good math skills or a good calculator or computer program.

But here are a few things the weatherman may not tell you when he starts talking about those dangerous wind chills:

• A person has to be facing into the wind with no facial protection for it to feel as cold as the weatherman says it will feel outside. If you cover your face (or a good part of it) or have the wind at your back, it's not going to feel as cold as the wind chill from the chart.

• Wind chills apparently do not take into account the added heat a body can produce to protect the face if enough clothing is worn to insulate the rest of the body. I say this because I should have suffered a lot of frostbite from time spent out in extreme cold and wind in years I lived and worked in the northern plains and Midwest, but I didn't. Fingers and toes were always the first to get cold even though they were covered.

• The calculations do not take into account the added warmth produced when in sunlight. A note on the NOAA website says bright sunshine can increase the windchill temperature by 10-18 degrees.

So, why don't the weathermen tell us that, with sunshine, it might even feel warmer than the actual temperature? Why don't they tell us that if we get out of the wind or wear enough clothing to protect ourselves from it, windchill won't be much of a factor?

I expect it makes a better story to tell folks on a 15 degree day that it will feel like minus 2 if the wind is blowing 20 mph. I'm still waiting to be told that, since it's a calm and sunny day, 22 degrees will feel like 40.

Come July, I suppose I might share my thoughts on the heat index, but I still have a little math homework to do since it is based on the following equation:

HI = -42.379 + 2.04901523*T + 10.14333127*RH - .22475541*T*RH - .00683783*T*T - .05481717*RH*RH + .00122874*T*T*RH + .00085282*T*RH*RH - .00000199*T*T*RH*RH.

It might be easier to just use the actual temperature, say it feels hot outside and let it go at that.

Randy Moll is the managing editor of the Westside Eagle Observer. He may be contacted by email at [email protected]. Opinions expressed are those of the author.