A fresh blast of Arctic air is poised to spill across a wide swath of the United States, and the latest polar vortex map ...

Major cities across the Northeast and Midwest are facing temperatures 10-20 degrees below average, according to forecasters.

Tornadoes, winter storms and even hurricanes - chances are you've heard at least one of those phenomena mentioned in the same sentence with the jet stream. Here's a meteorology 101 rundown about what ...