Flood Threat TX Interior
From
Mike Powell@618:250/10 to
All on Wed Jul 15 13:33:00 2026
AWUS01 KWNH 151001
FFGMPD
TXZ000-151600-
Mesoscale Precipitation Discussion 0725
NWS Weather Prediction Center College Park MD
600 AM EDT Wed Jul 15 2026
Areas affected...Texas Hill Country...South-Central Texas
Concerning...Heavy rainfall...Flash flooding likely
Valid 151000Z - 151600Z
SUMMARY...Slow-moving and concentrated bands of showers and
thunderstorms with extreme rainfall rates will continue this
morning across the TX Hill Country and some adjacent areas of
south-central TX. Areas of dangerous and life-threatening flash
flooding are expected, with the potential for locally catastrophic
impacts.
DISCUSSION...The latest GOES-E Proxy Visible satellite imagery
continues to show a well-defined mid-level trough axis that
extends from northern Mexico up across the TX Hill Country and
extending eastward all the way into the Lower MS Valley. However,
there is a strong embedded vort center drifting near the Rio
Grande River in close proximity to Del Rio, and this energy will
help focus a very moist and unstable airmass courtesy of a
persistent low-level jet into the TX Hill Country and adjacent
areas of south-central TX this morning.
The result is expected to be multiple slow-moving clusters and
bands of concentrated showers and thunderstorms with extreme
rainfall rates. PWs of 2.0 to 2.25 inches along with early morning
MLCAPE values already of 1500 to 2000+ J/kg will be supporting
rainfall rates of up to 2 to 3+ inches/hour.
As mentioned in the previous MPD, one other key contributor to
this will be the rather strong and persistent low to mid-level
convergence around the eastern flank of the vort center over the
TX Hill Country. This moisture convergence coupled with strongly
favorable upwind propagation Corfidi vectors for backbuilding and
cell-training will support not only enhanced hourly rainfall
rates, but also the persistence of them within these
semi-organized convective clusters and bands.
The latest 06Z HREF/REFS guidance and earlier runs of the
experimental WoFS suggest an expansion of convection this morning
now only across the TX Hill Country, but also some adjacent areas
of south-central TX off to the east. This will be connected to the aforementioned low-level jet and vort energy, but also interaction
with a weak stationary front that is in close proximity.
Additional rainfall totals this morning of 3 to 6 inches are
likely, with some spotty 8+ inch amounts possible just through
this morning. These additional rains will promote areas of
dangerous and life-threatening flash flooding, and especially
given already sensitive soil conditions. Potential will exist for
locally catastrophic flash flooding impacts.
Orrison
ATTN...WFO...CRP...EWX...FWD...MAF...SJT...
ATTN...RFC...FWR...NWC...
LAT...LON 31999999 31469873 30729775 29799716 28809745
28539842 28759993 29370113 30240214 31120221
31700178 31980113
$$
--- Scorpio BBS
* Origin: capitolcityonlinet.net * KY, USA (618:250/10)