Sunday, December 25, 2022

Vermont Christmas Climatology: Always Expect Big Weather Surprises From Santa

Snow falls from pine trees on Christmas morning, 2017 in
West Rutland, Vermont. A 3.5 inch snowfall ensured early
in the day ensured a white Christmas that year. 
 It looks like we're in for a cold and blustery Christmas this year in Vermont.

But, the weather won't be too, too unusual for Vermont. Which is a nice break from the extreme weather we've endured in the past few days. 

Still, our Christmas, 2022 will certainly buck recent trends of seeing warm holidays. Today's average temperature will be about ten degrees colder than average for this time of year. 

Christmas week as a whole is known for its sometimes bizarre weather, and we sure had that this year in the days leading up to the Big Day. 

With calmer weather today, in let's go down memory lane with the extremes and oddball weather of Christmases past.  

As any Vermonter knows, Christmas weather varies wildly year to year. Some years it's springlike. Others, you freeze your tush off. Some years are the gorgeous, traditional white Christmas, others look like mud season. 

For the record, the National Weather  Service office in Burlington, Vermont says the average high temperature on Christmas is 31, the low would be 15. Note that this is the "new" normal with climate change. The average Christmas decades ago was a little colder than that. 

On average, you'd expect 0.11 inches of precipitation, which would translate - if it's normal - to an inch of snow. 

All the record for highs, lows, snowiest, wettest etc for Christmas have a lot of asterisks. That's because these records only deal with Christmas Day.  But Christmas is a season, essentially, and the days around the holiday have sometimes been more impressive the actual date itself. The most extreme Christmas weeks were parts of exceptionally weird winters. 

On the actual date, the coldest Christmas was easily in 1980.  The "high" temperature that date in Burlington was minus 5 and the low was a nasty, nasty 25 below. I remember that Christmas as exceeding quiet, as you'd expect, since nobody wanted to go outdoors. 

That winter turned out to be one the weirdest in Vermont. December and January scored in the top 10 coldest. The second half of December featured 14 days below zero in Burlington, and all but one of the first 18 days of January were subzero. Then, that February ended up by far as the warmest on record.

The warmest Christmas was just recently, in 2020, in which the temperature peaked at 65 degrees in Burlington.  The high temperature occurred in the morning, but temperatures stayed at or abov 60 degrees well into the afternoon.  At one point on Christmas morning, Burlington was the warmest spot in the entire Lower 48.  

A very green Christmas, Instead of a snow covered ground,
daffodil shoots emerge in St. Albans, Vermont on 
Christmas Day, 2020, which was the warmest on record.
The temperature in Burlington that day was 65 degrees.

The snowiest Christmas in Burlington was in 1978, when 16.9 inches fell.  That was actually a relatively well-behaved storm, though. Sure, it was disruptive for travel, but at least it was festive, with not a lot of wind or containing any icy mixture. 

The 1978 storm also made for the "wettest" Christmas, as the snow melted down to 0.76 of a inch.

The asterisk for snowiest Christmas goes to 1969.  One of the most extreme winter storms in Vermont history began Christmas night and continued into the 28th. Not much snow fell Christmas night that year, so it doesn't qualify as snowiest Christmas. 

Burlington received 29.8 inches of snow in that huge storm, which finally ended on December 29. This 1969 storm was the biggest snowfall on record in Burlington under even bigger ones hit in January, 2010 and March, 2017.  As much as 44 inches pounded central Vermont. Eastern Vermont suffered a devastating ice storm in that episode.

The whitest Christmas, in terms of the amount of snow covering the ground, occurred just a year later, in 1970. While only 0.2 inches of snow fell on Christmas Day that year, there was 32 inches of snow on the ground. This was part of the snowiest winter on record in Burlington with 56.7 inches during December and 145.7 inches for the entire winter. (A whopping 28.8 inches fell just in the eight days leading up to Christmas Day, 1970).

The chances of having a white Christmas in Vermont ranged wildly, from about 60 percent in the Champlain Islands to virtually certain in cold Northeast Kingdom hollows like Island Pond.  We did manage to score a white Christmas this year.

Almost all of the snow cover melted during our extreme storm on December 23, only to return that evening during a burst of heavy snow. Most of us woke to a few inches of snow on the ground this morning. 

CHRISTMAS TRENDS

I took a look at Christmas average temperatures decade by decade in Burlington since the beginning of the 20th century.. Not surprisingly, with climate change, Christmases are a lot warmer now than they used to be. 

It's interesting that the holiday warmed slightly from the the first decade of the 20th century to the 1930s. 

Then it cooled off again, with average temperatures bottoming out in the upper teens to low 20s from about the early 1940s through the 1970s.

After that, the Christmas holiday in Burlington began to slowly warm up in the 1980s and 1990s. That trend accelerated starting around 2000.

Here's the average Christmas temperature in Burlington per decade:

  • Decade              Average Temperature
  • 1902-1911                 22.0
  • 1912-1921                 16.7
  • 1922-1931                 25.2
  • 1932-1941                 25.4
  • 1942-1951                 17.0
  • 1952-1961                 21.8
  • 1962-1971                 17.2
  • 1972-1981                 21.0
  • 1982-1991                 22.7
  • 1992-2001                 22.4
  • 2002-2011                 27.5
  • 2012-2021                 29.6

 

 

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