Nation's Cold Snap In Perspective: Intense But Far From The Worst Ever. Vermont Cold Wimpier, Too

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

The Washington Post had a good analysis of the cold wave that has been making headlines in the United States for the past several days now. 

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. 

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. 

I Know, I Know, Climate Change Gets Blamed For Everything, But Hear Me Out On Latest Megastorm

Green Mountain Power released this image of tree damage
in Vermont after last week's superstorm cut power to 
much of the state. Is climate change making these
extreme winter storms more likely? 

 The gigantic "bomb cyclone" storm that pummeled practically the entire United States last feel sure didn't feel like global warming.  

Blizzard and winter storm warnings covered parts or all of at least 17 states. More than half the Lower 48 was below zero.  It sleeted in Melbourne, Florida on Christmas Day.  So much for climate change, right?

Or not. There's a case to be made that climate change made last week's weather situation worse than it otherwise would have. Climate change doesn't only make things warmer. Often and under the right conditions, it can just make things more extreme.

That said, here's a caveat with this storm:  There's no proof climate change had anything to do with this, at least not yet. Scientists will probably study this huge, rambling system to learn if there was any connection. We can say there are consistencies with this storm and it's accompanying Arctic outbreak and climate change. 

First of all, climate change does not cancel winter. Sure, winters are warmer than they used to be. But for most of the United States, it's easily still often cold enough in our now balmier winters to have snow. 

Also, pretty much every winter storm that has ever existed needed warm air to survive. Low pressure systems in the winter pull warmth and moisture from places like the Gulf of Mexico or the warm Atlantic waters off the southeastern coast. 

This warm, wet air encounters the usual cold air that exists in winter. That air is forced to rise up and over that colder air. Rising air cools and condenses, and unleashes a literal blizzard of snowflakes.  This is just basic physics. 

Under climate change, that warm, moist air is even toastier than it used to be decades ago.  The warmer the air, the more moisture it can hold.   More moisture more often than not means more precipitation. So it follows that winter storms can produce heavier snow than they used to. They have more moisture to deal with, so they can make more snowflakes than storms did decades ago.

In last week's storm, however most places didn't have extreme amounts of snow, with the exception of places blasted by lake effect snows around the Great Lakes. 

The storm was certainly huge, both in how strong and big it was. Honestly, the storm was the largest in size that I can remember. This giant tempest was also able to pull down a rapidly advancing Arctic air mass that had its origins in Siberia. 

If you want a big Arctic outbreak and/or a big storm, you want a wildly meandering jet stream. No piddling mini southward excursions or wimpy northward turns here!  If the jet stream has a big plunge southward, it'll pull frigid Arctic air southward from near the poles. 

Then, if that big plunge turns a corner at the bottom and heads back northward, you probably have a big storm on your hands

One reason the storm was able to get so big was an enormous dip in the jet stream deep into the heart of the nation. Then, the jet stream  took a corresponding northward sweep up the East Coast and well into eastern Canada. 

Whether the jet stream can meander like crazy in the winter frequently depends on the polar vortex. The polar vortex, you remember, is that giant swirl of frigid air that's usually somewhere in or near the Arctic all winter. 

If the polar vortex is well north, and tightly wound, the truly frigid air stays up by the Arctic circle where it belongs. 

If the polar vortex weakens, it can get pulled, elongated and/or migrated south toward the mid-latitudes of  Asia, Europe or North America. The polar vortex can even break up into pieces temporarily.

When all this happens, trouble usually follow. It makes the jet stream meander all over the place and somebody gets a big Arctic blast and probably a nasty winter storm. 

 The jet stream depends upon a nice big contrast in temperatures between the Arctic and points further south. Such a contrast helps the jet stream "know its place" and not meander too much. The contrast probably encourages the polar vortex to keep its act together and not get weird or have a breakdown. 

 Here's the controversy:  We know the Arctic is warming faster than the mid-latitudes, where most of us live. There's not as much of a contrast between, say, Houston and Whitehorse as there used to be. This diminished contrast might be encouraging the jet stream to meander, with bigger dips southward and bigger bulges northward.

Bigger dips and bulges in general mean bigger, more powerful storms, and more wild Arctic outbreaks in the winter. 

Additionally, the Arctic warming might be messing with the Polar Vortex, that tightly wound core of super cold air that always hangs out in the far north during the winter.

Increasingly, it seems, this tightly wound vortex that would keep the coldest air above the Arctic circle gets oblong and oddly shaped, allowing the cold air to plunge south occasionally. Is climate change causing this?

As the Washington Post reports, the science isn't settled yet on whether the warming Arctic is creating more havoc with the jet stream, allowing these episodes of frigid air to blast into the United States, periodically. 

It'll take years of more observation and study to really see if there's a connection between the warming at the top of the world and these weird cold blast in otherwise relatively warm years.

However, as Jennifer Francis, seniors scientist at the Woodwell Climate Research Center tells the Washington Post: "We've see the same situation basically the last three years in a row.....Here we go again."

So we have anecdotal indications that climate change can paradoxically give us these huge winter storms and Arctic outbreaks. 

This is obviously bad news.  As of Monday morning, the death toll for last week's superstorm in the U.S. had risen to 46.  It'll probably go up more. This death toll is one of many sad consequences of a stormier, weirder weather world brought to us by climate change 

Even if it is indeed true that we'll have to endure more winter superstorms like the one we just had, overall winters are clearly warming. 

True to form, long range forecasts starting later this week and going through the first week of January call for above normal temperatures for most of the nation.

A week or two of relatively balmy weather in the middle of winter does nothing to prove or disprove climate change, but it is consistent with what we've been seeing in recent winters with the aftermath of these cold blasts and winter storms. 

(Almost) Relentless Cold To Shiver Your Timbers For Rest Of Month

A recent cold, dry day on frozen Lake Champlain in 
St. Albans, Vermont.  We're in a pattern of repeated Arctic
outbreaks with less precipitation than normal, and it 
looks like the pattern will extend at least through
the end of January and quite possibly beyond.

 There's a decent chance that Monday's snowstorm will be the only substantial one of the month in Vermont, but this January will be remembered for it's frigid temperatures.  

Burlington managed to receive 8.1 inches of snow Monday, enough to barely break the date's record for snowfall of 8.0 set in 1909.

Still, this was by Vermont standards a mid-sized storm, with most everyone receiving five to 10 inches of new snow.  A few spots managed to eek out a foot or even a bit more than that. 

So the storm was helpful, but we need more. We're still below normal.  Burlington is about nine inches behind what should have fallen by this time of year.  We'll probably fall further behind in the coming days because not all that much snow is in the forecast.

Instead, the unrelenting cold persists.  At least unrelenting compared to the series of mild winters we've had in recent years until now.

Today is another "wrong way" day with temperatures. We started before dawn with readings pretty close to 20 degrees, but readings will fall all day into the single numbers. Northwest winds will keep wind chills below zero. The colder parts of the region are under wind chill advisories, with "real feel" temperatures as low as 25 below. 

Get used to those wind chill alerts. We've had quite a few of them lately and we're surely in for more. 

Temperatures will dip below zero this evening.  But at least in western Vermont, we'll have  a "wrong way" night as temperatures start to actually rise after midnight again. 

Wednesday will actually be a rare balmy day. A little Alberta clipper storm from the west will throw a little light snow our way. It won't amount to much, but the warmer valleys will get into the low and mid 30s for a time.

Don't get used to it. We've been in that pattern for a couple weeks now in which one Arctic high pressure system after another crashes down from Canada and sends us into the deep freeze.

The next one should arrive Thursday with falling temperatures and another couple nights well below zero. Friday's highs should barely get above zero.

A few weather weenies have been in a tizzy over a few computer models bringing another nor'easter type storm sometime over the weekend or Monday.  I suppose it bears watching, but most indications at this point are it will go out to sea, or at least be too far east to affect Vermont much. So far, I'm not impressed, anyway. 

What looks likely is yet another reinforcing shot of Arctic air coming in to start next week. This January has a shot at being the coldest one in Vermont since 2004.  That year was the sixth coldest January on record. I'm not sure, but I don't think this January will score in the top ten coldest, as chilly as it has been. 

That depends on how intense the next few Arctic outbreaks are.