The polar vortex of ultra-cold air usually spins around the North Pole, but it sometimes ventures south into the U.S., Europe and Asia. Some experts say such cold air outbreaks are happening more frequently, paradoxically, because of a warming world.

An area stretching from Texas to Tennessee braced Wednesday for the expected arrival of freezing rain and snow, as some other parts of the country that already received an arctic blast this week prepared to go another round with the plunging polar vortex.

as some other parts of the country that already received an arctic blast this week prepared to go another round with the plunging polar vortex. Arkansas' capital, Little Rock, closed schools on ...

According to the NWS, the Arctic polar vortex is a powerful band of west-to-east winds that develops in the stratosphere, about 10 to 30 miles above the North Pole, during the winter season. It is always present near the poles, though it weakens during summer and intensifies in winter.

DENVER — A powerful arctic cold front arrived in Colorado on Friday and will keep the state very cold until Wednesday. The temperature could be below freezing for at least 114 consecutive hours ...

A new blast of Arctic air sweeping from north to south will bring bone-chilling temperatures to millions of Americans this weekend and next week.

things get a little chaotic. A weaker jet stream becomes wavy and unstable, like a loose rope in the wind. This instability allows cold Arctic air from the polar vortex to spill southward into ...

But during the winter, it is joined by a second atmospheric phenomenon dubbed the polar vortex. This swirl of frigid air, located more than 10 miles above Earth’s surface, strengthens each year ...

These outbreaks can happen when the polar vortex is in a weaker state, allowing cold air that is normally confined to the north to break off and move further south. Some experts say this is ...

A lobe of the polar vortex, a stormy ring that typically keeps ... Faster movement will cause the storm to form farther offshore and cause little impact, while slower movement will cause the ...

The polar vortex is responsible for next week’s cold, which will bring extreme cold as far as the deep south. The cold air will hang around Monday, Tuesday and Wednesday, bringing below-zero ...