Colorful jet stream visualization over Earth's Western Hemisphere.

What is the Jet Stream?

The jet stream is a narrow band of strong winds in the upper levels of Earth’s atmosphere, and it blows from west to east and provides a corridor for storms to follow as they circumnavigate the globe. Jet streams form along the boundaries of warm and cold air, and the wiggles of the jet stream play a large part in the weather you experience.

sleet in a glove

What is Sleet?

In the average winter, most of us will have to deal with frozen precipitation, not just snow. One of these types is sleet, and we’ll explain how it forms and the difference between it and a hailstone.

polar vortex diagram

What is a Polar Vortex?

Winter 2020-21 didn’t turn out as many thought. Most long-range forecasters thought La Niña would lead to a mild and uneventful winter. My weather station read 62 on Christmas Day in Pennsylvania! Well, the polar vortex had other plans.