I've remarked before that one of the milestones I use to gauge when the seasons are changing is when I turn the heat on. Turning the heat on in the house is one indication Fall has arrived This is different from the traditional, solar calendar based season, which started on the equinox almost four weeks ago. It turned out to be warm that day, then shortly after we entered a heat wave that lasted 2 weeks. My gauge takes into account the region, the climate, and the weather rather than how many hours of daylight we get. (Though daylight is important, too. I hate when it's dark when I get up in morning and dark before I finish work!)

By this milestone of turning on the heat, Fall fell last night. I switched it on when I saw that overnight lows would dip to 52° F (11° C). Granted, I set the thermostat at a miserly 69° (20.5° C) as our bedroom is upstairs where it stays a bit warmer (heat rises) and we both prefer it a bit on the cool side when sleeping anyway. And the heat barely ran, if at all, overnight as our house is fairly well insulated. Turning on the heat was mostly to backstop the temperature in case it might get cold inside for whatever reason.

Just because overnight temps are dropping does not mean the days are getting chilly, though. Today will be a bit cool at only 70, but the forecast for the next week shows highs in the mid- to high 70s (24-26° C). Hooray for nice weather during the day... and cool enough nights to sleep under a sheet without sweating.