Widespread Damage Expected With Squall Line

Severe Weather Update from SPC:
5:00pm edt - Moderate risk dropped; high-end slight risk for much of the region.
Looking at dewpoints and satellite imagery, instability is strong, but not as strong as expected. Therefore, still looking at wind damage along the line, but perhaps not as widespread as anticipated. Let's hope that trend continues.
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Quick Update from SPC:
12:35pm edt - No graphical changes made. Updated discussion includes support for strong tornadoes across far west KY. Next update by around 4pm or so.
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One of my favorite harbingers of storms is the warm, humid air combined with the presence of cumulus clouds in the morning hours. Typically, those cumulus clouds become favored suspects for thunderstorm development during the afternoon.

Technically, though, a decent cap should keep the precipitation chances down during the daylight hours. Nevertheless, a cold front will approach the region later this afternoon and evening accompanied by a damaging squall line.

Obviously, the cap will not hold. The loss of instability will be gradual during the nighttime hours, especially between 8pm and midnight. Expect widespread damaging winds along that line for anyone impacted before midnight. By 1:00-2:00am, scattered reports of damage can still be expected. This may include areas just east, such as Shelbyville and Frankfort.

The SPC still has Louisville on the edge of a moderate risk for severe weather. Depending on the speed of the entire squall line, Louisville may be upgraded to a moderate risk, as we will be in that 'before midnight' sector. The farther west one goes, the higher the risk for not just damaging straight-line winds but possible tornadoes.

This squall line has the potential for causing extensive damage along it. Power outages, downed trees and lines, and possible roof damage can be expected (as winds may gust to hurricane force in places).

I will update the SPC outlook within the hour. Another one should come out later this afternoon.

MS