North American Weather Center - Severe Weather Center

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The NEXRAD storm Table data includes the following criteria:

Mesocyclone (MESO)
The NEXRAD algorithms detect a three dimensional rotating section of a storm that is an indicator of severe weather.

Tornadic vortex signature (TVS)
Potential tornadic activity is detected by the NEXRAD algorithms within the mesocyclone.

Hail (HAIL)
The NEXRAD algorithms are detecting the probability of hail within the storm.

Hook Echo (HOOK)
The radar observation (ROBs) is detecting a hook echo, which is an indicator for potential tornadoes.

Watch Boxes
Thunderstorm and tornado watches issued by the Storm Prediction Center in Norman, OK.

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