SPC May 26, 2025 0600 UTC Day 1 Convective Outlook

SPC 1200Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1232 AM CDT Mon May 26 2025

Valid 261200Z - 271200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM WEST CENTRAL
TEXAS TO THE LOWER MISSISSIPPI VALLEY...

...SUMMARY...
Severe storms are expected from west-central Texas eastward into the
lower Mississippi Valley. Areas of large hail will be possible with
the primary risk becoming damaging winds. Marginally severe storms
will also be possible outside the Slight Risk area from the southern
Plains into the Southeast.

...Texas to the lower Mississippi Valley...

Large-scale height field will gradually be suppressed across the
southern Plains during the day1 period as upper troughing over the
southwestern U.S. advances east. This subtle change should allow the
primary synoptic front to gradually sag southeast, along with the
focus for organized severe.

Early this morning, an elongated corridor of scattered strong-severe
thunderstorms extended from AL, arcing into the Arklatex, then west
into the southern Plains. The western edge of this activity is
expected to gradually expand in areal coverage as an MCS evolves and
propagates across north central TX by sunrise. The MCS, or some
rejuvenated variant, will spread across the lower MS Valley during
the day as modest southwesterly 500mb flow translates across LA into
MS. While some weakening is likely after sunrise, boundary-layer
heating may contribute to robust development along the leading
convective outflow. Damaging winds, and perhaps some hail, are
possible with this activity.

Upstream, potentially stronger updrafts are expected with convection
that develops along the northeastern edge of a steep low-level lapse
rate plume. Models insist strong surface heating will occur across
far West TX into the Edwards Plateau. Convective temperatures should
easily be breached along/south of the synoptic front that will be
draped across this region. Supercells should be the initial storm
mode, and very large hail will likely be generated as seasonally
strong buoyancy will exist across this region. Forecast sounding for
SJT at 27/00z exhibits 3000 J/kg MLCAPE with 40kt 0-6km shear, and
PW values around 1.5 inch. Convection that develops across this
region should propagate southeast, possibly evolving into an MCS
during the evening. Probabilities may need to be increased across
this portion of TX in subsequent outlooks.

..Darrow/Thornton.. 05/26/2025

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