FOUS30 KWBC 240013 CCA
QPFERD

Excessive Rainfall Discussion...CORRECTED
NWS Weather Prediction Center College Park MD
713 PM EST Fri Jan 23 2026

Day 1
Valid 01Z Sat Jan 24 2026 - 12Z Sat Jan 24 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL IN AND NEAR THE
TEXAS HILL COUNTRY...

South-Central TX/TX Hill Country...
Maintained the low-end Marginal Risk area for a conditional flash=20
flood risk across the Hill Country later tonight. Overrunning=20
showers developed north of a front across South- Central TX
earlier today and continued to grow in areal coverage during the
afternoon. The 12Z HREF showed at least some potential for convective development later tonight (generally after 24/04Z) when models
generate a pool of 500-1000 J/kg of MU CAPE broadens across South=20
TX and 850 mb inflow strengthens. Differences remain between the
HREF and REFS but there was enough agreement for repeating/training
of cells to warrant a Marginal Risk area...especially in parts of=20
the area that has have minimal topsoil. That would allow heavy=20
rainfall to more readily run off.

Bann


Day 2
Valid 12Z Sat Jan 24 2026 - 12Z Sun Jan 25 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS THE
IMMEDIATE NORTHWEST GULF COAST...

Guidance trends in the 12z cycle led to further suppression of the
Marginal Risk to the immediate Middle and Upper TX coasts as well
as the southwest LA coast around to the mouth of the Atchafalaya
Basin of south-central LA. Precipitable water values, instability,
and the effective bulk shear forecast still support the idea of
heavy rainfall, but there's an increasing risk that it could occur
offshore. Hourly amounts to 2" with local totals to 4" remain
possible. Should the south to southeast model trend continue, the
Marginal Risk area could be dropped on later cycles.

Roth


Day 3
Valid 12Z Sun Jan 25 2026 - 12Z Mon Jan 26 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS THE
INTERIOR SOUTHEAST...

Models are in pretty good agreement concerning heavy rainfall
across interior portions of the Southeast. Precipitable water
values of ~1.25" exist within a cool atmosphere, high enough for
saturation to occur. Low-level inflow/effective bulk shear is
sufficient for convective organization. The biggest question is in
regards to MU CAPE, with NAM guidance advertising 250-500 J/kg
occurring upstream of the heavy rainfall. This should be enough to
sustain 1"+ hourly rainfall amounts, at times. A check of model
soundings indicate the areas of the southernmost Appalachians are
expected to be above freezing/as mild as the 40sF due to northward
guidance trends in the winter weather system moving by to the
north, which led to an extension of the Marginal Risk area across
northernmost Georgia into far western/southwestern NC. These areas
have significant relief and should be less sensitive to any recent
dryness. The extension into the southernmost Appalachians was agreeable/coordinated with the GSP/Greer SC forecast office.

Roth

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_wlhHmXtehQTOA05NH_gl1pwRwr5RdWM84AH1ORRLAtc= DXjsokVs_nR3MEOFEFpjvrBxC5fDc6o9KE7EmkY-XpQhEEE$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_wlhHmXtehQTOA05NH_gl1pwRwr5RdWM84AH1ORRLAtc= DXjsokVs_nR3MEOFEFpjvrBxC5fDc6o9KE7EmkY-q9lZ9JE$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_wlhHmXtehQTOA05NH_gl1pwRwr5RdWM84AH1ORRLAtc= DXjsokVs_nR3MEOFEFpjvrBxC5fDc6o9KE7EmkY-ZUXO-1g$=20

=3D =3D =3D
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