CENTRAL TEXAS TORNADO OUTBREAK
Shortly after the noon briefing revealed a rope cloud along the cold front in
central texas and extreme instability, an isolated supercell was developing
in McLennan county. After a visual inspection with the naked eye, it was
noted the environmental wind shear, dispite the models forecast, was actually
decent with the storm having a nice
overshooting top, well-defined back edge and anvil to the storm. A
sounding was taken around 3pm 30 miles east of the storm to obtain an environmental
account of the large-scale thermodynamic structure supporting the supercell development. The sounding revealed
very little cap and large cape values. The next attempt was made to get to the
southern end of the storm to launch into the updraft of the cell. By the time we
reached the meso, the wall cloud was getting wrapped up the rain curtain just west
of Granger. Since new additional towers kept backbuilding on the southwest side of the
storms, it made it impossible to get to a new updraft region. The M-CLASS returned
to B/CS to launch another sounding around 8pm to characterize the environment that
storms developing north of Brazos county were feeding off of.
Sounding taken at 20z east of supercell. (a or b)
Sounding taken at 02z at CLL. (a or b)
Both soundings overlaid with RUC 18z 3 hour forecast.
ADRAD radar loop of convection.
QuickTime movie of the Jarrell Tornado caught on tape by Texas A&M Grad Students
and created by Discovery Online.
Note: The images above are temporary while we work on producing better ones.
All images created are solely owned and copywrited by Texas A&M Universtiy.
The fact that made this situation so devastating was the constant back building
right along I-35. This was the position of the frontal boundary during the day. The
surface boundary convergence in combination with a short wave trough in a west/northwesterly flow
and a very unstable uncapped atmosphere lead to the inevitable.
Radar Loops from ADRAD and TOGA
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These movies are under construction. Check back for more and better stuff!
Jarrell Seminar
