Severe Storm Outlook Narrative (AC)
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298
ACUS02 KWNS 120519
SWODY2
SPC AC 120517

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1217 AM CDT Mon Oct 12 2026

Valid 131200Z - 141200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS INTO THE LOWER MISSOURI VALLEY...

...SUMMARY...
Widely scattered severe storms capable of large hail and damaging
winds appear possible over portions of the central and southern
Plains into the lower Missouri Valley Tuesday afternoon into night.
More isolated severe weather may occur from southwest Texas into the
mid Mississippi Valley, and in parts of New York.

...Synopsis...

An upper low will progress through the Great Basin toward the
central Rockies/Four Corners with a downstream belt of enhanced
mid/upper-level winds stretching from the southern Rockies through
the Great Lakes into the Northeast. Within that airstream, a
short-wave trough will progress from the Great Lakes into the
Northeast, while a more subtle impulse translates from the southern
Rockies into the Upper Midwest.

At the surface, an area of low pressure will develop from the Great
Lakes into the Northeast with a trailing front stretching through
the southern Great Lakes and southern IA into central or southwest
KS, where it will link with a secondary surface low. Dryline will
extend south from the KS low to along the TX-NM border by late
afternoon or early evening.


...Central and Southern Plains into the Mid-Mississippi Valley...

Level-2/Slight Risk wind and hail probabilities have been extended
to the St. Joseph and Kansas City, MO vicinities in this forecast
update to account for greater severe storm potential in a favorable
CAPE-shear parameter space.

Southerly low-level winds will maintain a moist boundary layer
within the warm sector with dewpoints in the mid 60s to low-mid 70s
F. While midlevel lapse rates will not be particularly steep, the
moist environment coupled with daytime heating will contribute to a
moderately unstable air mass by afternoon with MLCAPE of 1000-2000
J/kg. Slight height falls aloft combined with daytime heating and
convergence along the surface boundaries are expected to eliminate
remaining capping, yielding thunderstorm development by mid
afternoon initially from the TX and OK Panhandles into central KS.
Subsequent storm development is anticipated by late afternoon into
evening farther northeast along the front into the lower-MO Valley.
A more isolated wind and hail threat could spread into portions of
southern IA and IL Tuesday evening and night. Finally, a separate
round of strong to severe storms appears possible Tuesday night into
early Wednesday over portions of southwest TX and the Permian Basin.

Within the level-2/Slight Risk area, vertically veering wind
profiles with 40-50 kt of deep-layer shear will favor supercells as
the initial storm mode with large hail being the primary hazard,
both along and to the north of the front. There is some model signal
that the KS segment of the front may tend to surge south during the
afternoon into evening, which would suggest the potential for a
relatively quick transition to a more outflow-dominant storm mode
and an associated damaging wind threat. Tornado potential will be
conditional on supercell storm modes persisting into evening when
the low-level jet and associated near-ground shear increase.


...New York...

Showers and thunderstorms may be ongoing at 12Z Tuesday within a
zone of low-level warm advection and moisture transport preceding
the short-wave trough and surface low. Lingering clouds and areas of
precipitation are likely to inhibit air mass destabilization,
especially with eastward extent into the Hudson Valley. However,
where cloud breaks can occur, the presence of boundary-layer
dewpoints in the low-mid 60s will contribute to modest MLCAPE up to
500-750 J/kg by afternoon. On the condition that surface-based
storms can develop and become sustained, the existence of a strongly
sheared kinematic environment (particularly in the low levels) would
favor supercells capable of a tornado or two and damaging winds.
This forecast update will maintain level-1/Marginal Risk
probabilities due to uncertainties in the extent of air mass
destabilization.

..Mead.. 10/12/2026

$$