981
AWUS01 KWNH 031951
FFGMPD
LAZ000-TXZ000-032250-

Mesoscale Precipitation Discussion 0216
NWS Weather Prediction Center College Park MD
351 PM EDT Fri May 03 2024

Areas affected...southeastern TX

Concerning...Heavy rainfall...Flash flooding likely

Valid 031949Z - 032250Z

Summary...Areas of flash flooding are likely to continue in the
short term over southeastern TX but with decreasing coverage and
possible downward trend in flash flood potential through 22Z.

Discussion...1930Z radar and visible/infrared satellite imagery
showed continued thunderstorms, scattered over southeastern TX
with repeating and training, such as recently observed over
southeastern Montgomery County where MRMS-derived rainfall rates
were 1 to 2+ in/hr. A number of outflow boundaries were present,
with overrunning of low level flow supporting the regeneration of
convective activity. Two of these outflow boundaries were observed
on visible imagery and extended from SE to NW across I-10. There
has been a trend of warming cloud tops overall for the region over
the past 2-3 hours, but locally heavy rain falling atop saturated
soils was still leading to lingering flash flood concerns.

RAP analysis soundings within the cold pool indicate convection is
rooted in the 850-700 mb layer. Sizable elevated CAPE of 1000 to
2000 J/kg was estimated across the region along with
unidirectional SW flow above the LFC via RAP analysis and SPC
mesoanalysis data, with little to no CIN. Short term trends in
observations and select short term hires model guidance that have
at least a halfway decent handle on the ongoing activity suggest
that at least a short term flash flood threat will continue over
portions of southeastern TX over the next 2-3 hours. Recent runs
of the HRRR may be ending the flash flood threat too quickly.
Current thinking is for a localized but likely threat for training
cells to continue from near a Houston to College Station line with
subsequent development backbuilding toward the SW with time. The
good news is that soil moisture decreases with southwestward
extent which when combined with an anticipated decrease in the
coverage of cells, should help to limit the areal extent of
impacts.

Otto

...Please see www.wpc.ncep.noaa.gov for graphic product...

ATTN...WFO...EWX...FWD...HGX...LCH...

ATTN...RFC...LMRFC...WGRFC...NWC...

LAT...LON   30999592 30799511 30589473 30419439 29989381
            29689374 29539417 29119499 29189557 29349668
            29769697 30289700 30779669