Alachua Co. EMWIN Project

Alachua Co. EMWIN Project
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Wednesday, June 30, 2010

Gust Front Funnel Cloud ('Gustnado')
June 29, 2010
Gainesville, FL

Date/Time: June 29, 2010, 5:44pm ET
Location: Gainesville, Alachua County, FL

[Image Copyright (C) Steven A. Robicsec 2009. All Rights Reserved.]

Photo by Dr. Steven A Robicsek, MD, PhD. Taken June 29, 2010 at 5:44pm, from atop the Seagle Building on W. University Avenue, looking west at the Ben Hill Griffith Stadium.

This is not actually a "tornado", but something more like a large dust devil. If you remember your spotter training, a true funnel cloud "hangs pendant from a wall cloud." Gustnadoes are actually not part of or connected to the cloud base. From the New World Encyclopedia...

"A gustnado (gust front tornado) is a small, vertical swirl associated with a gust front or downburst. Because they are technically not associated with the cloud base, there is some debate as to whether or not gustnadoes are actually tornadoes. They are formed when fast moving cold, dry outflow air from a thunderstorm is blown through a mass of stationary, warm, moist air near the outflow boundary, resulting in a "rolling" effect (often exemplified through a roll cloud). If low level wind shear is strong enough, the rotation can be turned horizontally (or diagonally) and make contact with the ground. The result is a gustnado. They usually cause small areas of heavier rotational wind damage among areas of straight-line wind damage. It is also worth noting that since they are absent of any Coriolis influence from a mesocyclone, they seem to be alternately cyclonic and anticyclonic without preference."

This is truly an amazing shot. It's difficult enough to catch any KIND of a funnel here in Alachua County; but to catch one placed perfectly right next to the stadium like this is sure to destine this particular photo for some small amount of fame in the least. Congratulations to Steve on nailing this one! This is a great shot!

I've talked to Bill Quinlan, TV-20 Meteorologist, and he advises that in talking with the NWS they thought they were seeing a convergence of two outflow boundaries in the vicinity. Bill said that he was looking at the radar when this was actually happening and he said that this funnel occured at the very outside edge of the storm, where the outflow/gust front was.

We're not exactly sure just WHERE the funnel is actually touching down...behind the O'Connell Center?...over Lake Alice? It is obviously picking up a lot of dust. We know that the point of photography is at the Seagle Building. And the funnel is located between the southern edge of the west wall of the stadium and the south end zone score board (the building with the antennas on top of it). This narrows things down a bit. But now we need someone at ground level from that area who actually saw it so that they can point to us a differrent specific direction and this will allow us to accurately pinpoint exactly where the event actually occured. So if there's anyone who lives in any of the dorms in that vicinity who actually saw this, please do contact us so that we can try to narrow this down more.

This photograph demonstrates perfectly how there are things out there which can LOOK like a funnel cloud or a tornado, but which actually are not. This is an excellent "look-a-like", and I've been hunting for these kinds of photographs for a while.

(This may well be the first-ever photograph of a gust front funnel ever taken in Alachua County.)

For more examples of severe related photography and videography, see the Alachua County Area Storm Spotter's Field Guide.

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