... it's going to be about our locally frosty weather, after all.
Yes, those favored locations (Freeport, Monroe, Rochelle, and any other valley) may very well see some frost come morning. Rochelle started today at 37°, so they're really going to be chilly tonight, I'd wager! My mom said the rooftops in our neighborhood in Galena had frost on them this morning. There'll be plenty more of that tomorrow morning, and perhaps Saturday morning too.
Our good friends at the Quad Cities National Weather Service put up a link to find autumn climate data. The Illinois PDF has lots of locations listed, although I only took a gander at Rockford. The data show the date for which there is a 10%, 50%, and 90% chance of a certain temperature being reached. It sounds confusing, but it's really not so bad.
We have a 10% chance of recording 36° by September 18, a 50% chance of doing so by September 29, and a 90% chance by October 10.
We have a 10% chance of recording 32° by September 21, 50% chance by October 6, and 90% chance by October 21.
We have a 10% chance of recording 28° by October 1, 50% chance by October 18, and 90% chance by November 4.
Why do we pick these temperature thresholds? At 36°, we start dealing with frost, since the temperature at the surface tends to be colder than where the thermometer is located (six feet off the ground). 32° is of course the freezing point, and 28° is when we starting thinking about a hard freeze that kills vegetation.
No comments:
Post a Comment