Mission Summary 4/29


VORTEX intercepted an HP supercell that developed in the vicinity of Lake Texoma, and moved to Denison/Sherman TX, and then to SW of Sherman. This supercell had a velocity differential of nearly 80 kt in the mesocyclone. Low-level rotation was clearly discernible just east of a heavy rain core. Many teams observed hail of golfball to baseball size. None of the teams observed surface winds much stronger than 35 kt, despite operating quite close to the mesocyclone. A tornado was reported by law enforcement just west of Sherman. However, VORTEX teams were in position to observe a tornado if one had formed, so we await photographic evidence from any observer to convince us of this report.
Good data were obtained in all parts of the storm by the mobile mesonet. One good updraft sounding showing nearly undilute ascent was obtained. Forward-flank soundings were obtained by one team along the forward flank baroclinic region. The NOAA P-3 obtained a large number of pseudo-dual Doppler volume scans with very striking reflectivity features.

Erik Rasmussen
Jerry Straka

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