Severe storms bringing potentially damaging winds were sweeping through the Chicago area late Friday night, as a fast-moving squall line raced through the state. The fast-moving line of storms was capable of producing destructive winds over 70 miles per hour and potential tornadoes,

After a day of near record-high temperatures and sunny skies, the Chicago area is bracing for possibly severe storms and dangerously high winds heading into Saturday. A severe thunderstorm watch is currently in effect for all Illinois counties of the Chicago area until 2 a.

As many as 150 million people in the U.S. face a potential severe weather outbreak in the coming days. Storms will likely reach the Tampa Bay area late Sunday, bringing a marginal risk of severe weather to part of the region.

A severe weather outbreak is expected on Saturday in Alabama, according to the National Weather Service. NOAA’s Storm Prediction Center has added -- and now expanded as of Thursday afternoon -- a rarely-used Level 4 out of 5 risk for parts of a large part of Alabama for Saturday.

Saturday’s setup is shaping up to be a particularly dangerous situation. Increased instability (how quickly the air rises) and wind shear (how the air changes in wind direction and speed with height) will lead to the risk of severe storms capable of producing tornadoes.