The north eastern section of the U.S. could about to head into a prolonged freeze-up next week, thanks to energy from the Polar Vortex sinking south.
The term “Polar Vortex” is used to describe the usually tightly packed core of very cold temperatures over the north pole during Winter. Sometimes, sections of the polar vortex can break off, and fall south, into mid Latitude areas. When this happens, places like the U.S. and Europe can experience very much colder than average conditions. Not all polar outbreaks will be severe, but all will be cold.
Take a look at this following chart, showing temperature anomalies for next Tuesday (21st January). Notice the blues across the central and eastern half of the country, indicating a very cold pattern. (Source of image: pivotalweather.com)
A number of computer models are suggesting that these colder than average temperatures could become fairly persistent, lasting throughout next week. It’s possible that some moisture interactions from the Pacific or Atlantic jet could engage with the expected cold air to produce snow events or even snow storms next week, so be aware of that risk. Colder temperatures are likely, for example in NYC a high of 27F is expected next week. In Montreal, highs of 3F are expected by next week. Colder than average, yes, but not unusual for Winter.
Before next week, though, some pretty wintry conditions are expected this weekend. A winter storm is expected to produce some severe weather, including ice, snow, and strong winds. The strong winds will mostly be reserved to the very far North East (Maine), however widely some heavy snowfall is expected this weekend across the Great Lakes and North East. Between 3 and 7″ of snow is likely quite widely, however in some isolated spots over 12″ is possible. So some tricky conditions are expected this weekend.
This following snowfall accumulation chart from Pivotalweather.com shows the wide mass of snow expected this weekend, bear in mind these are just an early indication and to be taken with a pinch of salt at this stage.
So, after a lousy start, winter is finally set to get going across the North East of the U.S. Some very cold conditions, much colder than average, are likely next week for the North East. These anomalously cold temperatures may become quite prolonged, as in the past such patterns can become quite “fixed”, and hard to shift. As ever though, there’s some uncertainty involved here. Keep an eye on updates in the future and warnings issued by NOAA or local authorities.