21 December 2019 — 1708 mst
Welcome to winter — and to global warming winter
timeanddate.com and the U.S. Naval Observatory are excellent sources of information on astronomic phenomena. Timeanddate’s sunrise-sunset tables also provide the times of civil, nautical, and astronomical, twilight, and meridian transit of the sun.
Astronomical winter begins at 1719 MST today. Meterological winter began on 1 December. At meridian transit today, 1235 MST in Kalispell, the sun was 18.4 degrees above the horizon, the lowest transit of the year. The time of sunset has been getting later for several days, but so has the time of sunrise, which will continue until early January.
Seasons also are defined by temperature. For example, in Finland and Sweden, spring begins when the average temperature rises above freezing.
Yesterday’s high at Glacier International Airport (KGPI) was 51°F. Today’s high, at least 54°F. This is global warming winter.