An outflow boundary is a meteorological term that refers to the boundary between two air masses created by a thunderstorm's downdraft. If you've ever stood outside during a thunderstorm and felt the cool rush of air preceding a storm, you've experienced an outflow boundary.
On March 21-23, 2022, a multi-day severe weather and tornado outbreak with 78 confirmed tornadoes struck portions of the Deep South. The most affected areas were Texas and the eastern New Orleans metropolitan area northward into Mississippi.
A squall line is a line of strong and severe thunderstorms common in the spring and summer and often produce strong winds, lightning, heavy rain, and hail. Squall lines often form ahead of cold fronts but can develop independently if several strong thunderstorms merge.
Friday, December 10, 2021, will be a day that residents of four US states will remember for a very long time. Spurred by a strong winter cold front pushing through the region, severe weather and tornadoes ripped through the Mississippi Valley and mid-South, including a long-track tornado referred to as the "Quad State Tornado."
Severe thunderstorms are common in the Southeast U.S and Midwest. However, they can happen almost anywhere (even in unusual places, like Alaska). If weather conditions are favorable for severe thunderstorms, the National Weather Service issues a severe thunderstorm watch.