A multi-platform analysis of the Central Texas floods of May 13, 2004

Strong, deep convective storms developed during the early morning hours of May 13, 2004 over portions of central Texas southeast of Waco, northwest of Houston and east of Austin. A mesoscale convective complex evolved within hours and back-built along an intensifying mesoscale boundary that extended from Georgetown (north of Austin) to Conroe (north of Houston).

The gradient across this boundary was fed by intense (rain-cooled) outflow from the storms north of the boundary and a strong onshore flow of tropical air from the nearby Gulf of Mexico. In less than twelve hours, many areas of Milam and Robertson counties received 6 to 12 inches of precipitation, with some areas receiving 15 inches of rain. Widespread dangerous flooding resulted, particularly across eastern Milam and western Robertson counties.

In this presentation, the authors utilize a multi-platform approach to analyzing this unusual event. the analysis utilizes data from several nearby WSR88D radars, surface and upper air rawinsonde observations, model output from the NCEP suite of models, and profiler data from the NOAA Profiler Network. The latter source is of particular significance because the NOAA profiler at Ledbetter, TX was strategically located in the inflow region of the developing and maturing MCS.