Tuesday, June 18, 2013

Stuttgart Funnel Cloud

What was that in Stuttgart Monday: cold air funnel, tropical funnel, funnel cloud, tornado?  Here's what I can tell you.  So far, there has been no reports of damage and MOST of the pictures indicate it never touched down.  That means it wasn't a tornado.  I have my doubts calling it a "cold air funnel".  There was not a true cold core low which typically produces these harmless spin ups high up in the sky.  Also, the pictures I have seen out of Stuttgart don't really have the cold air funnel look.  

Was it a tropical type of funnel cloud?   Basically, these funnels are caused by vertical stretching of some spin in the atmosphere.  These are usually not associated with supercell thunderstorms and develop in tropical environments.  We do know according to sounding data Monday, plus just stepping outside, the low level air mass was extremely moist.  

There was not a tornado warning in effect at the time.  Based on radar evidence, one would not have been issued.  The rotation was very weak.  If it was a cold air funnel, those are never warned by the NWS.  Even if it was a typical tropical like funnel, they usually do not last long and don't touch down often.
I have talked to several meteorologists at the National Weather Service and the debate continues exactly what to call this.  What I can tell you is that until we get any proof it touched down, this was NOT a tornado.  I'm leaning to the tropical funnel theory right now.  I'll keep you updated if I hear anything new.

This picture was obviously taken from a far distance. However, this does show it's possible for it to have briefly touched down.  It's very difficult to know for sure based on this picture.  It does look very close though!

This picture as well shows the funnel close to the ground
Another picture of it from Stuttgart.

All the reports indicate the funnel was on the north side of Stuttgart, however, based on radar data, it looks like the west side of the storm showed the highest potential for any rotation.  See that tiny hook west of town?

Looking at the velocity data, there was some weak rotation west-southwest of Stuttgart.  But this is NOT where all the reports came from which makes this a little more puzzling.  Where the reds and greens come together indicates where that rotation is located.  Based on this radar image, it's very, very weak and not enough for a tornado warning to be issued.

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