Wiki tells me that astronomical Winter is from the December solstice to the Spring equinox. I don't understand why this is the "winter" that winds up on calendars.

Early in life, I assumed that the seasons were arranged:

Spring: 1 Mar - 31 May
Summer: 1 Jun - 31 Aug
Fall: 1 Sept - 31 Nov
Winter: 1 Dec - 28 Feb

I still think that makes more meteorological sense for where I live than the astronomical dates.