Is it winter or is it still fall?  What’s the old duck test to suggest something can be identified by its typical characteristics?  If it looks like a duck, walks like a duck, and quacks like a duck then it probably is a duck.  Well, it looks like winter, feels like winter, and drives like winter so it’s probably winter.  However, it’s really still fall until the winter solstice, which this year is December 21st.   We follow the astronomical calendar in which our seasons are defined by two solstices and two equinoxes.  By that measurement, winter will begin December 21, spring will begin next March 20th,  and summer starts June 21st.   But, there is another way of measuring seasons used by meteorologists which is more closely aligned to temperature cycles and our monthly calendars.  These meteorological seasons are simpler than astronomical seasons.   The calendar year is divided into four seasons of three months each.  As one climatologist put it, dealing with whole month chunks of data rather than fractions of months was more economical and made more sense.  So, by that way of measuring winter started yesterday (well, this year we could say it started a couple of weeks ago but let’s not quibble).  On December 21st we might casually take note of the fact that winter “officially” is starting with the shortest day of the year.  Apparently, Australia, New Zealand, Pakistan, and Russia use meteorological seasons making it easier to keep climate statistics, although I doubt it makes it any easier to make accurate weather forecasts. 

That’s Coffeetalk.  I’m Vic Dubois.