Severe weather across much of the Southeast US

By Scott Bachmeier • 4 May 2021

GOES-16 “Red” Visible (0.64 µm) images, with SPC Storm Reports plotted in red [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) include time-matched plots of SPC Storm Reports (predominantly widespread damaging winds, with some large hail and a few tornadoes) produced by a large and long-lived Mesoscale Convective System (MCS) that moved eastward across much of Mississippi and Alabama on 04 May 2021. The strong winds — with some gusts in excess of 70 mph — caused power outages which affected several hundred thousand residents (and persisted into the next day: MS | AL).

The corresponding 1-minute GOES-16 “Clean” Infrared Window (10.35 µm) images (below) showed numerous overshooting tops that exhibited infrared brightness temperatures in the -75 to -70ºC range (white pixels embedded within black areas). The MCS also produced heavy rainfall and flooding in parts of northern Alabama.

GOES-16 “Clean” Infrared Window (10.35 µm) images, with SPC Storm Reports plotted in cyan [click to play animation | MP4]

? It rained a little yesterday…

Rainfall totals of 5-7″ (locally higher) fell across parts of the Birmingham metro & much of Shelby Counties. This lead to significant flooding in many areas. Thankfully, there were no fatalities. #alwx pic.twitter.com/ko0TmYhNUo

— NWS Birmingham (@NWSBirmingham) May 5, 2021

Larger-scale views of 5-minute CONUS Sector GOES-16 Visible and Infrared images are shown below. Several additional MCSs produced a variety of severe weather across other parts of the Southeast US.