Diane & I are members of that fraternity of those who have spent a few winters in interior Alaska.  Up there 50 degrees below zero doesn’t need any qualifying statements.  I think that most of us from that group wonder about the validity of the wind chill factor (WCF).  At 40° F degrees with a 15 mph wind the wind chill factor is supposed to be 31° F.  Does water freeze at that WCF?
        I imagine that the WCF was invented by Chicago TV weathermen to gain sympathy for their region in the winter.  I picture them about to report on the dangers of being outdoors at 20° F with a 10 mph wind coming off Lake Michigan and then feeling a little foolish after glancing at the weather map and seeing a temperature of 52° below zero at Fairbanks, AK.  Equalizing outcomes is getting to be the American way, so someone must have come up with the WCF to make Chicago’s cold just as cold as Fairbank’s cold.
        The party is over.  The concept of the WCF has just received a crippling blow. In the OHLIN UPDATE 10-09-11, I wrote about our Senegalese AC.  I asked what the WCF would be when our bedroom was 90° F with the fans blowing at 10 mph.  Several alert readers responded.  The wind chill facture calculation gives a WCF of 96° F (hotter than the air temperature) in our bedroom under the mosquito net in front of the blowing fan.  This proves that the concept of WCF is total hooey.  If the fan is off you will drown in your own sweat, but when it is on you can sleep comfortably (Well, you are not always comfortable, but usually you can doze off most of the night).
        My advice this winter to Chicago’s TV weathermen is to avoid using the discredited WCF.  It will only lower the viewer’s confidence in the validity of the weather report.  If you need to warn them about threats to the public, tell them how to take precautions against the invasion of those flying carp on the Illinois River.  Tell the viewers about the hidden danger from CAF (carp acceleration factor).