(AP) — The plunging polar vortex brought subfreezing temperatures Tuesday to some of the southernmost points of the U.S., threatening to dump snow on parts of Texas and Oklahoma in coming days ...

Residents across the country from the Northern Plains to the tip of Maine are bracing for dangerously low temperatures ...

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Major winter storm brings heavy snow to East Coast as Arctic blast puts millions under warnings from Plains to Maine ...

Sub-zero wind chills are forecast to reach as far south as Oklahoma and the Tennessee ... this latest cold snap comes from a disruption in the polar vortex, the ring of cold air usually trapped ...

A strong polar vortex in the stratosphere has brought subzero temperatures to the Midwest, Mid-Atlantic and deep into the ...

It's like "bomb cyclone" or "firenado." It seems like the sort of phenomenon that would be responsible for the ...

When there are disturbances in which the Jet Stream weakens, it can become wobbly. This allows the cold air to plunge southwards. A disrupted polar vortex does not happen every year. Very much so what ...

A polar vortex dipping down from Siberia is bringing a cold front with frigid temperatures to millions Americans. See maps of ...