Above: A Von Karman vortex street downwind of the Canary Island chain in the eastern Atlantic Ocean off the coast of Africa on Feb. 27, 2015. Image credit: NASA Worldview. Editor's note: Meteorologist ...

A massive winter storm is about to hit much of the United States, bringing snow, sleet, icy rain, and exceptionally low temperatures. Here’s how to protect yourself, especially if you have a medical ...