Supercell in Salt Lake City

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On Twitter, we tracked a supercell thunderstorm in the Salt Lake City area this afternoon. 

As there was significant rotation, the NWS added a "tornado possible" tag to its severe thunderstorm warning. While I certainly agreed the tornado risk was worth the notice, I wish they would go ahead and issue a tornado warning in these cases. 

On radar, it looked like a classic Great Plains tornado-producing thunderstorm with a hook echo and (not shown) mild rotation. 
Salt Lake Terminal Doppler Weather Radar
Image from my Twitter storm coverage
Large hail fell (1.25") and there was an unconfirmed report of 60+mph winds. While other photos showed a well-defined wall cloud (often a precursor to a tornado), I've not seen any reports of tornado damage. 

In 1999, there was a fatal tornado in this same region that killed one person and injured 80. Damage was $310 million damage (!) in today's dollars. 

These situations can be difficult where tornadoes are geographically rare but I thought the Salt Lake City office of the NWS did a fine job.

Update: 4:20pm CDT

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