Amarillo, Texas, May 6, 2008—A supercell—the strongest and most severe type of thunderstorm—lights up the sky over Amarillo.

The supercell would eventually form a tornadic vortex signature, signaling a high probability of forming dangerous twisters.

The supercell was part of a line of storms that dumped torrential rain and large hail in parts of west Texas, but no major damage or injuries were reported.

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