274
ACUS01 KWNS 190557
SWODY1
SPC AC 190555

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1155 PM CST Tue Nov 18 2025

Valid 191200Z - 201200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
SOUTHERN PLAINS INTO WESTERN PARTS OF THE OZARKS...

...SUMMARY...
Isolated severe storms are possible across the southern Plains into
western parts of the Ozarks, mainly late this afternoon into
tonight.

...Synopsis...
A deep upper-level trough will move slowly eastward across the
Southwest later today into tonight. Downstream of this system, weak
lee troughing will become established across the southern/central
High Plains. A surface boundary initially draped from north TX into
the ArkLaTex will move northward as a warm front, with rich
boundary-layer moisture spreading into parts of southern/central
OK/AR during the afternoon and evening.

...Southern Plains into western parts of the Ozarks...
A broad region of at least isolated severe potential remains evident
across the southern Plains. Within this region, one or more areas of
locally greater hail potential may evolve, but confidence in the
details is low at this time.

Relatively steep midlevel lapse rates atop dewpoints in the 60s to
near 70 F will result in moderate destabilization along/south of the
warm front by late afternoon. Large-scale ascent appears rather
nebulous into early evening, but isolated storm development cannot
be ruled out by late afternoon, especially in the vicinity of the
warm front. Storm coverage will increase through the evening into
late tonight from southwest into northwest TX and southern OK, as
ascent related to the approaching trough begins to overspread the
region.

Deep-layer shear will be sufficient for at least occasional storm
organization, with isolated supercells possible. Hail is expected to
be the most common hazard, though isolated strong/damaging gusts may
also occur. Regarding tornado potential, a secondary low-level
moisture surge (with dewpoints approaching 70 F) could result in a
brief tornado threat with any evening supercells across southwest
TX. Elsewhere, a nonzero tornado threat could also evolve with any
persistent supercells near the warm front, but this scenario remains
uncertain due to generally modest low-level flow/shear.

A separate area of primarily elevated storm development will be
possible late tonight from southeast KS/northeast OK into
central/southern MO. MUCAPE increasing to near 1000 J/kg and
sufficient effective shear could support an isolated hail threat
with the strongest storms in this regime.

...Southeast AZ into southwest NM...
Widespread convection is expected later today from southeast AZ into
southwest/south-central NM, in response to the eastward-moving upper
trough/low. Buoyancy will likely remain weak due to limited heating,
which may tend to suppress the organized severe threat, but strong
deep-layer shear could support occasional storm organization.
Confidence is too low to include probabilities at this time, but
stronger heating/destabilization than currently expected could
result in some severe potential.

..Dean/Moore.. 11/19/2025

$$