151
AWUS01 KWNH 080626
FFGMPD
TXZ000-081130-

Mesoscale Precipitation Discussion 0589
NWS Weather Prediction Center College Park MD
224 AM EDT Mon Jul 08 2024

Areas affected...Southeast TX

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

Valid 080625Z - 081130Z

SUMMARY...Hurricane Beryl continues to approach the middle Texas
coast as heavy rainbands move onshore. Very heavy rainfall rates
associated these rainbands and the gradual arrival of Beryl`s
inner core/central convection will support increasing coverage of
flash flooding which will eventually become significant toward
dawn.

DISCUSSION...Hurricane Beryl as of 06Z (1AM CDT) was positioned
near 28.2N 95.9W or about 30 miles miles south-southeast of
Matagorda, TX and is moving north-northwest at 10 mph. GOES-E
satellite imagery has been showing better convective organization
over the last few hours, with occasional brief hints of an eye
showing up in both IR and Proxy Visible satellite images. Cold
convective tops in particular are noted around the northern
semicircle of the cyclone, and this will set the stage for very
heavy rainfall to wrap northwestward and inland across southeast
TX over the next several hours as Beryl prepares for landfall.

Already there have been heavy outer rainbands ahead of Beryl
moving inland across portions of Matagorda and Brazoria counties
where increasingly strong and convergent low-level flow coupled
with enhanced moisture and instability transport has been yielding
an increasingly organized character to the convective banding.

MLCAPE values of near 1500 J/kg have noted with the stronger
bands, and there has been a notable increase in 0-3 km shear
profiles which will encourage there being stronger and more
organized updrafts including some supercell/mesocyclone structures
that will be conducive to enhanced rainfall rates.

Given the extremely moist environment and improving thermodynamic
and kinematic profiles, the rainfall rates within the stronger and
more organized convective bands will easily reach 2 to 3
inches/hour, and this is very strongly supported by the 00Z HREF
guidance. The latest satellite and radar trends coupled with the
00Z HREF guidance supports the idea of heavy convective bands in
particular impacting Matagorda and Brazoria counties over the next
few hours along with gradual arrival of central core convection
leading up to dawn. Meanwhile, impacts will be on the increase
farther up the coast into Galveston County, and inland across
Harris, Fort Bend and Wharton counties.

As Beryl`s inner core/eyewall convection arrives toward dawn,
extreme rainfall impacts should ensue, and given the expectation
of as much 4 to 6+ inches of rain by dawn (especially over
Matagorda and Brazoria counties), numerous to widespread areas of
flash flooding should commence, with considerable/severe impacts
likely to be underway or soon beginning.

Orrison

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

ATTN...WFO...CRP...HGX...

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

LAT...LON   30069576 29919494 29449456 28899520 28709560
            28489623 29019666 29799637