Who's asking: Richard Bostwick, Hallowell (or is that North Hallowell?), ME
You know, I always assumed that there was a difference -- but guess what? Not really. Meteorologists can and do use "mostly sunny" and "partly cloudy" to describe the same set of weather conditions, depending on their mood and the time of day. ("Mostly sunny" doesn't work at night.) They may be more likely to use "mostly sunny" if the weather is clearing, and more likely to use "partly cloudy," if things are getting overcast, but otherwise it's a half-empty/half-full decision.
I don't know why I assumed that predicting the weather was a more exact science than that.
Anyway, today is mostly sunny, before more snow comes tomorrow and Thursday. The thinnest of ice skins is starting to show up on the Kennebec, and last night's low temperature of 18 was too cold even for Dizzy.
The happiest of birthdays today to Mr. Ashton LeBourgeois, who grows daily more distinguished-looking.