The Vortex

As I write this--after midnight Sunday in the Midwest and Eastern time zones--many places there have already recorded their high temperature for Monday.  Monday and Tuesday (in some places Wednesday) will be more dangerously cold than any days in at least 20 years there.  The upper Midwest (Minnesota, North Dakota) was already freezing on Sunday, also hit by snow and wind (up to 10 inches in Chicago.)
Further east in Indianapolis and in Ohio the combination of wind, frigid cold and ice are already closing highways as well as schools and businesses.

 From a relatively balmy Sunday, Pittsburgh goes into the deep freeze Monday and Tuesday, and is scheduled to emerge to another balmy day on Wednesday.  Very cold temps and wind will eventually extend not only along the northern East Coast but deep into the South, with single digit temps forecast for Charlotte and Atlanta.  All kinds of low temp records are likely to be broken over much of the country.

Cities like Chicago and Pittsburgh are taking this especially seriously because a lot of people think they know what cold is, but they don't.  They simply haven't experienced it, or at least not in a very long time.  And with windchills possible to 50 or even 70 below, even brief exposure can mean frostbite or worse.  This is dangerous weather.

Down in Washington (where a forecast Zero will break its record) there will be wags chortling (especially since Congress reconvenes Monday) that obviously there's no global warming going on here .  Of course by now only the purposely ignorant can ignore that global heating models have shown effects including heavy snowfalls and frigid temps.  But it seems a lot of people make a very good living being purposely ignorant.

But this may be an even more specific example of a global heating effect.  One prominent theory (being promoted as fact in headlines) is that these literally Arctic temps are due to a "polar vortex," the Arctic's equivalent of a super-cold hurricane.  Because these frigid winds whip around in a circle they usually stay in the Arctic, but this may be a weakened polar vortex that has partly blown south--and one prominent theory is that it has been weakened by warmer air as a result of the melting of Arctic ice, which is a result of global heating.

NOAA scientists suggest this as they study other evidence for a "warm Arctic/cold continent" effect.  Data from 2009 and 2010 suggest this is a pattern.  But the idea that Washington would be hit with dangerously cold temperatures as a result of the climate crisis was already dramatized in Kim Stanley Robinson's Science in the Capital trilogy (2004-7.)  So it's not a new idea.

Of course, the skeptics can take the colder winter temperatures, figure in the hotter summers, and come up with a temperate average that will gosh just prove that this climate crisis isn't happening at all.  This is what happens in the circular winds of Washington.