… And how often does it occur?
An article in the February 14th edition of the Springfield, Illinois State Journal-Register mentioned an interesting incident that took place in December, 1840-something.
According to an obscure tome of Sangamon County history, Joe Pioneer was riding his horse into Springfield to purchase his marriage license. The weather was ±40F and drizzling (not unusual for December in central Illinois). On the way into town, he notices a black cloud toward the west and hears a rumbling sound. A few minutes later, a cold front moves in and he is instantly frozen to his saddle as the temperature drops to ±0F. The writer of the SJ-R article postulates that the temperature dropped 40 degrees in about one second.
Sounds like bullshit to me. First of all, a black cloud in the west in the winter means that it’s about to get warmer, not colder, as it means that a warm front is bringing precipitation. It’s when high-pressure and cold fronts clear the skies of clouds that it gets really cold. Secondly, I’ve heard of drastic temperature changes (like gaining or losing as much as 70 degrees F) over the course of a day (or even an hour), but not 40 degrees in one second.
Any closet meteorologists heard of this phenomenon? How often does it happen? When & where was the last time it happened in modern times?