915
ACUS01 KWNS 261947
SWODY1
SPC AC 261946

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0246 PM CDT Sat Apr 26 2025

Valid 262000Z - 271200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR EASTERN NEW
MEXICO AND THE PERMIAN BASIN AND PARTS OF THE TEXARKANA REGION...

...SUMMARY...
Scattered severe thunderstorms are possible over eastern New Mexico
into parts of west Texas this afternoon through the evening.  A
threat for very large hail and possibly a couple of tornadoes are
the primary risks.  Scattered damaging gusts are possible this
afternoon for parts of the Red River Valley.

...20z Update...
The previous forecast largely remains on track with the only notable
change being an eastward shift/expansion of 15% wind probabilities
(Slight risk) across portions of southeast OK, northeast TX, and
into far southwest AR. As of 19 UTC, regional radar mosaics show
deepening thunderstorms along a residual outflow boundary/effective
warm front ahead of a decaying MCS. Along this boundary,
temperatures have warmed into the low 80s with upper 60s/low 70s
dewpoints, resulting in MLCAPE exceeding 2000 J/kg. A recent ACARS
sounding from DFW sampled 30-35 knot mid-level flow over the region,
which should be sufficient for some storm organization/longevity
with an attendant threat for all hazards. Storm interactions should
favor clustering through late afternoon and may support a focused
corridor of wind damage/gust potential downstream of the developing
storms. See the previous discussion below and MCDs #568 and #569 for
additional details.

..Moore.. 04/26/2025

.PREV DISCUSSION... /ISSUED 1143 AM CDT Sat Apr 26 2025/

...NM into the Southern Plains and ArkLaTex...
Visible satellite-radar composite shows a front/outflow pushing
south across South Plains and Caprock over portions of west TX and
westward into parts of eastern NM.  This boundary will likely stall
later this afternoon while moist upslope flow is maintained from the
Permian Basin northwestward into southeast/eastern NM.  Surface
observations show a reservoir of lower to mid 60s dewpoints over
southeast NM and west TX south of the boundary.  Moderately strong
west-southwesterly mid to high-level flow will extend east from the
base of a West Coast trough into the southern Great Plains today.

Strong heating over eastern NM will aid in moderate destabilization
(1000-2500 J/kg MLCAPE) from parts of northeast NM southward into
the Eastern Plains/Permian Basin where buoyancy will be greatest.
Models shows gradual erosion of convective inhibition later this
afternoon with isolated to scattered storms developing in the
vicinity of the dryline/composite front.  Steep 700-500 mb lapse
rates sampled on the 12z Midland, TX raob atop a deep/moist boundary
layer will support supercell development in conjunction with a
veering and gradually strengthening wind profile.  Large to very
large hail will be possible with a few of these stronger storms.  A
tornado risk may develop during the late afternoon/early evening.
Some of this activity may grow upscale into a small cluster this
evening posing a hail/wind threat is moves east-southeast into parts
of west TX.

Farther east, an MCS will continue east across OK this afternoon.
Moist low levels in the vicinity of the Red River may enable a
re-invigoration of storms this afternoon.  Damaging gusts appear to
be the primary risk with these storms.

...Northeast/Mid Atlantic/Carolinas...
A shortwave trough will continue moving through southern Ontario and
the adjacent Lower Great Lakes. A cold front will progress eastward,
moving through the northern Mid-Atlantic by this evening and the
remainder of the Mid-Atlantic States by tonight. A relatively moist
airmass is already in place ahead of this front, and thunderstorm
development appears likely along the front as it moves eastward
throughout the period. Highest coverage is anticipated from the
Hudson Valley/NYC vicinity southward across the Delmarva to the
Chesapeake Bay.

Gradually strengthening midlevel flow and deep-layer shear could
support a few stronger cells/clusters during the afternoon and
evening. Diurnal heating will be tempered by cloud cover, limiting
the overall buoyancy and updraft magnitude. Even so, some locally
damaging wind and small to near-severe hail could accompany
the strongest storms. Best overlap between the buoyancy and shear is
expected from NJ into the Delmarva vicinity from 18Z to 21Z.

$$