Subj : Heavy Rain - Deep So TX - flooding likely
To   : All
From : Mike Powell
Date : Wed May 27 2026 08:15:42

AWUS01 KWNH 271200
FFGMPD
TXZ000-271459-

Mesoscale Precipitation Discussion 0256
NWS Weather Prediction Center College Park MD
759 AM EDT Wed May 27 2026

Areas affected...portions of Deep South Texas

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

Valid 271159Z - 271459Z

Summary...Flash flood potential continues as a convective complex
spreads 1-2.5 inch/hr rain rates across the region this morning.

Discussion...An intense convective complex continues to migrate
across Deep South Texas this morning.  The northern portion of the
complex (extending from near Karnes City to near Corpus Christi)
was fairly progressive, with only isolated mergers noted that were
boosting local rain rates above 2 inches/hr.  FFGs are low in
these areas from prior rainfall, and FFG exceedences were noted.=20
Flash flood potential will likely exist for the next couple hours
as this part of the complex reaches the middle Texas coast through 14Z.

Of somewhat greater concern is focused, training convection on the
southwestern side of this complex.  Convection in that area was
oriented more parallel to steering flow aloft while remaining
closer to steep mid-level lapse rates aloft, supporting
backbuilding.  A mid-level wave was evident per objective analyses
along the Rio Grande Valley near Cotulla.  That wave should
continue to make slow northeastward progress through south Texas
this morning, prompting continued, upstream updraft development.=20
The temporal extent of this backbuilding is a bit uncertain -
though it appears that at least two more hours of backbuilding
convection (and rates approaching 3 inches/hr) are possible.=20
Flash flooding is expected - especially if these downpours can
begin to affect more populated areas.

Cook

ATTN...WFO...BRO...CRP...EWX...HGX...

ATTN...RFC...FWR...NWC...

LAT...LON   30179711 29969549 28899531 27739645 26719708=20
            26109729 26199856 26939979 27940007 28519909=20
            28739834 29989832=20

$$
--- MultiMail/DOS
 * Origin: ILink: Project Scorpio TEST (454:1/105.6)

.