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Satellite
Imagery
 

Visible Satellite Imagery

 
The above image shows three discrete anvil shields associated with supercell thunderstorms. The northern-most storm was the one that spawned the Newcastle-Moore EF-5 tornado. The second likely produced the tornadoes near Marlow and Bray.
 
The satellite loop above shows how rapidly supercells formed during the afternoon of May 20th.
 
Satellite Loop from the NOAA Visualizations YouTube Channel