Polar vortex redux? U.S. forecasters say it could hit next week

[December 09, 2016]  By Timothy Mclaughlin

CHICAGO (Reuters) - Forecasters are sending chills down some spines with a prediction that much of the northern half of the United States could see frigid weather next week similar to life-threatening lows the polar vortex brought to parts of the country in 2014.

Anticipation of a freezing blast began to build this week when weather maps and forecast models showed similarities between next week's system and one that developed in January 2014.

"Upper-level atmosphere configuration very similar in scale & magnitude as infamous Jan 2014 #PolarVortex popularized by me and @afreedma," meteorologist Ryan Maue said on Twitter on Tuesday alongside maps comparing the two weather systems.

The southward shift in the polar vortex in 2014 brought the Midwest some of its coldest weather in two decades. Icy conditions snarled travel and thousands of flights were canceled or delayed.

Frigid temperatures combined with gusting winds to create life-threatening wind chills as low as 60 degrees Fahrenheit below zero (minus 51 Celsius) that killed at least nine people.

The coldest weather next week is expected in the Midwest and Northeastern starting around Tuesday, according to forecasts that show temperatures in the single digits in some cities.

"The air mass on the way for the middle of December is likely to be substantially colder when compared to that of this past week and this weekend," AccuWeather meteorologist Paul Pastelok wrote on Thursday.

Temperatures from the Northern and Central plains to wide swathes of the Midwest are likely to drop by between 5 and 20 degrees Fahrenheit compared to temperatures this week, according to AccuWeather.

The Chicago skyline is framed by icicles in Chicago, Illinois, January 8, 2014. REUTERS/Jim Young

It is unclear how far south the cold air will be felt, according to Pastelok.

Chicago, the largest city in the Midwest, is bracing for temperatures in the teens next week, according to an AccuWeather forecast, which showed a low of 17 Fahrenheit (minus 8 Celsius) for Wednesday and Thursday.

Further north in Minnesota, Minneapolis-St. Paul NBC affiliate KARE forecasted temperatures dropping to 10 degrees Fahrenheit (minus 12 Celsius) on Tuesday of next week, then 8 degrees (minus 13 Celsius) on Wednesday.

(Reporting by Timothy McLaughlin in Chicago; Editing by James Dalgleish)

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