Severe Storm Outlook Narrative (AC)
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14
000
ACUS02 KWNS 231730
SWODY2
SPC AC 231729

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1229 PM CDT Sat Mar 23 2024

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM
NORTHWEST/NORTH-CENTRAL OK INTO WESTERN AND CENTRAL KS...

...SUMMARY...
Isolated to scattered severe thunderstorms should develop Sunday
afternoon and persist through Sunday night across parts of the
southern/central Plains. Large hail and a few tornadoes should be
the main threats, but occasional severe winds may also occur.

...Synopsis...
A low-amplitude, southern-stream shortwave trough is forecast to
move quickly from its initial position over the Lower CO River
Valley/western AZ eastward across the Southwest and then more
northeastward, reaching the central/southern High Plains by the
early afternoon. A northeastward progression will continue
thereafter, with the wave moving into the Lower MO Valley during the
evening and Mid MS Valley overnight. Strong mid-level flow will
accompany this shortwave, with 70-80 kt of 500-mb flow spreading
across the southern Plains throughout the day and across the Lower
MO Valley and Mid MS Valley overnight.

Progression of this shortwave will help induce deep surface
cyclogenesis across the central High Plains. By Sunday afternoon, a
sub-985 mb low will likely be over the southern CO/KS border
vicinity, with a dryline arcing southeastward from this low across
the OK Panhandle and then southward across western OK and into
southwest TX. This low is then forecast to move eastward across KS,
with the an attendant dryline only making minor eastward progress
until after midnight when more eastward push is anticipated again.

...Central/Southern Plains...
General consensus within the guidance places low 50s dewpoints over
western OK early Sunday morning, with higher dewpoints still south
of the Red River. Low to mid 60s dewpoints will likely still be
along the Lower TX Coast. A robust mass response is anticipated,
with strong low-level flow contributing to notable moisture return.
Even so, dewpoints will likely still be in the low to mid 50s across
western OK as the dryline moves into the region during the
afternoon. Additionally, early period precipitation and widespread
cloud cover will temper heating, especially from central portions of
KS and OK eastward/northeastward. As a result, while the overall
upper pattern and resulting wind fields match a typical
southern/central Plains severe event, the lack of better low-level
moisture will act as a major limiting factor.

Initiation appears most probable across southwest KS during the late
afternoon (around 21Z) near the surface low. Slightly deeper
boundary-layer mixing is possible in this area, and dewpoints are
only expected to be in the 40s. However, cold mid-level temperatures
and strong ascent (both from the approaching shortwave trough and
more mesoscale near the low and dryline) should be sufficient for
storm development. Vertical wind profiles in this area support storm
organization and an initially discrete supercell mode is
anticipated. Initiation farther south across western OK and
northwest TX is more uncertain, owing to the persistence of warm low
to mid-level temperatures and weaker large-scale ascent. As such, a
more conditional potential exists in these areas with favorable wind
profiles supporting updraft organization with any updrafts that are
able to mature.

Hail will be the primary severe risk with the initial development,
although strong downdrafts are possible as well. There is some
potential for upscale growth into one or more bowing segments as the
storms move eastward during the evening, but the narrowness of the
warm sector will likely lead to a more elevated storm character
while also contributing to decreasing updraft intensity. Even so,
the low-level jet is expected to strengthen as these storms move
eastward into south-central KS/north-central OK. Consequently, there
could be a short duration where surface-based storms interact with
this strengthening low-level flow, resulting in a low-probability
tornado risk.

As mentioned in the synopsis, the eastward progression dryline will
likely slow (or maybe even stall) during the late afternoon into the
evening. It is then expected to continue eastward/southeastward
overnight as its parent low moves eastward. Additional storm
development is anticipated along this boundary from south-central OK
into the TX Hill Country once it begins to move eastward again
(03Z-06Z) . A few stronger storms are possible, particularly in TX
Hill Country where buoyancy will be greatest, with an attendant
threat for large hail and/or damaging gusts. Thereafter,
undercutting nature of the dryline will result in a largely
anafrontal storm character and limited severe risk.

..Mosier.. 03/23/2024

$$


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.