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| Brutal cold waves are still always possible in Vermont, but they are becoming less and less likely or severe as climate change continues to take hold |
It's true that this Arctic cold snap was a humdinger. A few hundred daily low temperature records were set in a pretty wide area of the nation.
Nashville, Tennessee got below zero for only the second time since 1996. Thirty states had wind chill warnings or advisories. It was 54 below in Montana, with wind chills of 70 below.
In that Washington Post article, Matthew Cappucci writes:
"But despite the bitter cold, few monthly or all-time cold records were set. Simply stated, even a severe and disruptive Arctic outbreak isn't netting the kinds of records or headlines that this of the past did."....
.....The Earth is heating up. Warm extremes are turning warmer, and the cold generally isn't as cold. Human-caused climate warming is moderating cold snaps, making them less severe. They can still be bitter and dangerous, but they're not quite as bad as they used to be."
As of Wednesday, more than 330 daily record low temperatures have been set this month in the United States at many of the thousands of weather stations scattered around the United States.
Daily records are relatively easy to beat, especially if a cold snap hits on a date that by coincidence, have historically had few particularly cold days. All-time monthly records are much harder to beat, and there have only been two of them in this Arctic outbreak.
All-time records for any month are really, really hard to achieve, and so far we haven't seen any this month.
Most cold snaps are not lasting very long either, as opposed to some winters, like 1936, 1969, 1977 and 1978 that went on for weeks.
The national cold wave that we've had this week is already in the process of breaking down, after just a few days. By next week, pretty much the entire nation is forecast to be warmer than average.
Weeks like this in which record lows across the nation outnumber record highs are becoming rare, too. As Cappucci notes. Nowadays, it's usually the opposite.
Overall all of 2023, there were 31,611 warm weather records compared to only 10,493 cold weather records.
Back in the bad old days, or good old days, depending on your perspective, some historic national cold waves made this one look like a January thaw.
In 1899, an intense cold wave and blizzard sent temperatures down to an incredible minus 2 in Tallahassee, Florida. There's an old photo of lawmakers have a snowball fight on the Florida capital steps that day.
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| This cartoon is slowly becoming less and less relevant in cold states like Vermont as climate change generally makes severe Arctic outbreaks less frequent, less intense and less long-lasting than they used to be. |
That 1899 cold blast sent temperatures down to 9 below in Atlanta, Georgia and 15 below in Washington DC. Every state in the U.S. (Hawaii wasn't a state then) got below zero.
In February, 1936, it got as cold as 58 below in South Dakota and 60 below in North Dakota.
The average temperature for a five week period ending 4th the close of February in Devils Lake, North Dakota was an incredible 21 below. Langdon, North Dakota remained continuously below zero for 41 consecutive days.
January, 1949 was the coldest on record in all of the far western states. Snow fell in downtown San Diego. Los Angeles saw snow on three consecutive days.
As recently as 1977, on this date, January 19, a cold wave created snow flurries for the first time on record around Miami, Florida. Arguably the last truly destructive freeze in Florida was in 1985.
The only recent cold wave I can think of that even sort of rivaled those of the past was the one in February, 2021. More than 250 all-tine cold records were set or tied in an area ranging from the Canadian border to Texas and Louisiana. Cold waves like this are now exceptionally rare. I'm guessing we won't ever see anything like February, 2021 again.
By the way, that February, 2021 cold wave fueled speculation that climate change was messing with Arctic weather circulations in the winter. Perhaps a warmer world was warping the polar vortex and the jet stream, making such intense cold waves an occasional risk despite the fact that overall we are warming.
The idea that the polar atmospheric circulation is getting all mucked up by climate change is still a matter of debate. It's not quite settled science yet.
VERMONT PERSPECTIVE
Starting today, Vermont is forecast to endure three consecutive days with highs in the single numbers and teens, with lows within a few degrees either side of zero.
This is going to seem bitterly cold, because we haven't had any truly frigid weather yet. We're not acclimatized to what should be regarded as a run of the mill January cold spell.
Remarkably, through Thursday, the temperature in Burlington so far this winter had never gotten lower than the teens. That I'm sure is by far the latest in the season it hasn't gotten under 10 degrees yet.
Despite the warmer winters, it can still get frigid in Vermont. Every once in a while it can get to 20 below in Burlington, Vermont but that has become rare. The last time it was 20 below zero in Burlington was on January 7, 2018.
If I'm not mistaken, the last time it was colder than 25 below in Burlington was in January, 1994. Back in the 1960s and 1970s, it would get that cold during a good half of all winters.
Arctic cold snaps in Vermont have tended to get brief, too. In decades past, we'd sometimes have a week where every day got into the teens, 20s and 30s below zero. That's changed. I haven't seen a sharp cold spell last more than three or four days since the early 1980s.
From a historical perspective, this weekend's expected cold is absolutely no big deal. In past decades, it would have been regarded as pretty seasonable.
Here are a few bone chilling extremes that just might be permanently a thing of the past, thanks to climate change:
In January, 1857, temperatures fell into the 30s and 40s below zero across most of Vermont. At that time, most thermometers had mercury, which freezes at 40 below, so it's hard to tell exactly how cold it got. Burlington had a low of 29 below and a "high" of 16 below.
The entire winter of 1917-18 was frigid in Vermont, The temperature was continuously below freezing at Burlington from December 26 to February 11, except for a few hours on the afternoon of January 11.
Incredibly, the temperature was continuously under 10 below from the evening of December 26 to the late morning of December 31, 1917 in Burlington.
In the winter of 1933-34, temperatures got below zero on 45 days in Burlington, including 23 days that were in the teens or 20s below zero. This included a late December cold snap that dropped temperatures to 50 below zero in Bloomfield, Vermont, to this day the coldest ever measured in Vermont.
In January 1968, high temperatures in Burlington were below zero for five consecutive days and each morning during that spell were in the 20s below zero. Twelve days that month were in the teens below zero.
Arguably the last of the greatest Vermont cold spells was in February, 1979. All but one of 11 consecutive days from February 9-19 were in the teens and 20s below zero in Burlington. The all-time record low in the city of 30 below was tied on February 12.
In West Burke, all but two days in a 10 day stretch ending on February 21 were in the 30s below zero. The two "warm" days were in the 20s below.
Despite the warmth of recent winters, we're sure to have in the future a few nasty winters thrown in which temperatures get far below zero, or stay below zero for a week or more. But it won't happen much. Warm winters like the one we're experiencing now will be the norm.
This is definitely not your grandfather's Vermont winter climate.
1912,1918,1920,1981,1982,1994,2004. were the only years January mean was in the single digits in St Johnsbury
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