Polar Vortex Arrives: Here’s your Dittohead Repellant
December 8, 2016
A punishing blast of Arctic air will plunge into the northern half of the Lower 48 in five to seven days, dispensing some of the most frigid air since 2014 or 2015 in some areas.
“[The] upper-level atmosphere configuration [is] very similar in scale and magnitude as infamous January 2014 #PolarVortex”, tweeted Ryan Maue, a meteorologist with WeatherBell Analytics.
Computer models are unanimous in predicting that such a cold wave will occur, although they differ some on exactly how cold and how far south and east the Arctic air will penetrate. It is unlikely that this cold wave will be as intense as the January 2014 event because it is happening earlier in the winter and less snow is on the ground in North America (snow cover acts like a freezer and helps cold air masses stay cold when they exit the Arctic).
The bitter cold air is expected to first arrive in the northern Rockies and northern Plains on Sunday. It should reach Chicago on Tuesday and the northeast United States by Wednesday or Thursday.
While subject to change, the GFS model predicts temperatures from Chicago to western Montana to be 30 to 50 degrees colder than normal next Wednesday morning.