AWUS01 KWNH 261057
FFGMPD
LAZ000-TXZ000-261655-

Mesoscale Precipitation Discussion 0732
NWS Weather Prediction Center College Park MD
656 AM EDT Fri Jul 26 2024

Areas affected...Portions of Eastern TX into West-Central and
Southwest LA

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

Valid 261055Z - 261655Z

SUMMARY...Additional areas of heavy rainfall should tend to
continue this morning across areas of eastern TX and west-central
to southwest LA. Flash flooding will remain likely including
continued concerns for locally considerable urban flash flooding.

DISCUSSION...The early-morning GOES-E IR satellite imagery shows a
rather impressive cold-topped convective wedge (with tops to -60
to -65 C) near the upper TX coast and generally advancing east of
Galveston Bay to the immediate offshore waters, However, radar
imagery does show some of the heavier showers and thunderstorms
with this still impacting some inland areas of southeast TX, with
the activity also encroaching on southwest LA.

An elongated axis of vort energy is noted along much of the middle
and upper TX coast and up across interior areas of eastern TX
around the eastern flank of a broader mid-level trough over the
southern Plains. This energy is interacting with a very deep
tropical airmass and axis of stronger instability that is pooled
up across the northwest Gulf of Mexico and inland to some extent
over far southeast TX and far southwest LA. In fact, MLCAPE values
of 1500 to 2500 J/kg are noted across these areas with PWs of 2.0
to 2.25 inches.

The ongoing convection is likely to continue going through the
morning hours given the set-up which is also being facilitated by
favorable right-entrance region upper-level jet dynamics and a
convergent southerly low-level jet of 20 to 30 kts that is nosed
up along to the TX/LA border.

Generally the focus for the heaviest rainfall totals in near-term
going through at least mid-morning should continue to be over
areas of far southeast TX which over the next 1 to 3 hours will
likely include portions of the Beaumont-Port Arthur vicinity, but
this convection is expected to advance into some areas of
southwest LA, and eventually the Lake Charles vicinity may come
under impacts from this convection. Some of the rainfall rates
with these cells are likely to reach 2 to 3 inches/hour. Galveston
Airport in the last hour (4AM to 5AM CDT) alone reported 2.38
inches as these storms crossed through.

Additional areas of heavy rain are also noted farther north away
from the coast across parts of eastern TX and into west-central LA
where antecedent conditions are already quite wet and locally
saturated from recent heavy rainfall. High streamflows are noted
more regionally also via the latest USGS gauge data.

Therefore, with the potential for an additional 3 to 5+ inches of
rain locally this morning, and the sensitive ground conditions,
additional areas of flash flooding are likely.

Orrison

ATTN...WFO...HGX...LCH...SHV...

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

LAT...LON   32019350 31809281 31189243 30399238 29679263 
            29599344 29339437 28809551 28989604 29549595 
            30159575 30819518 31689421 
--- SBBSecho 3.20-Linux
 * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (618:250/1)