NORFOLK, Va. — Have you ever wondered why some winters are mild while others bring freezing temperatures and snowstorms? One of the key players in these dramatic shifts is something called the polar ...

Don't be fooled by the string of uneventful weather — the polar vortex is rebooting and will take another swing, or several, at the greater Philadelphia region, leading to a turbulent weather pattern ...

It is now likely that the coldest period of sustained cold weather is behind us after gripping the Eastern U.S. for the first part of December. Warmer temperatures are expected for Christmas and into ...

The coldest air of the early winter season is blasting the eastern U.S. on Monday with single-digit temperatures with the wind chill, as the Polar Vortex unravels and, with it, brings dangerous arctic ...

The polar vortex has broken, and severe temperatures are set to dominate most of the country in the coming days. Temperatures in the 10s are forecast for much of the Northeast, and subzero ...

Add Yahoo as a preferred source to see more of our stories on Google. A map of the polar vortex that is bringing frigid temperatures to parts of the U.S. (AccuWeather) The first of three rounds of ...

A polar vortex will bring arctic air and subzero temperatures to parts of the U.S. through the middle of the month, according to AccuWeather. This first of three likely rounds will impact the U.S.

Frigid temperatures are expected to impact much of the central and eastern United States in the coming weeks. The first of three polar vortex systems is expected this month, according to AccuWeather.

The polar vortex is so back, and in some parts of the country, the weather system will bring with it up to a foot of snow. If “polar vortex” is giving you déjà vu, that’s because we’ve heard it before ...