Severe Storm Outlook Narrative (AC)
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058
ACUS02 KWNS 210515
SWODY2
SPC AC 210513

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1213 AM CDT Sat Sep 21 2024

Valid 221200Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM WEST TEXAS
INTO CENTRAL/SOUTHERN MISSOURI...

...SUMMARY...
Isolated severe thunderstorms are possible on Sunday from west Texas
to central/southern Missouri.

...Southern Plains to Mid-MS Valley...

Forecast guidance has trended somewhat southward with severe
potential on Sunday, and the Marginal risk (level 1 of 5) has been
adjusted to reflect latest model trends.

An upper shortwave trough over the central/southern Rockies Sunday
morning will eject east to the mid-MS Valley by Monday morning. This
will bring a belt of 40-50 kt mid/upper southwesterly flow over the
region. At the surface, a cold front will develop southeast from
near Lake Michigan to northwest Texas at midday to the Ohio Valley
and central Texas by 12z Monday. A seasonally moist airmass will be
in place ahead of the front, with surface dewpoints in the mid to
upper 60s F forecast. Some uncertainty remains in where the corridor
of greater strong/severe storm potential will develop, mainly driven
by ongoing convection across parts of the region Sunday morning.
Nevertheless, where pockets of greater heating occur, favorable
vertical shear and increasing forcing from both the surface front
and the ejecting midlevel wave, will support organized storm
development. Damaging gusts will be the main hazard with
thunderstorm clusters and line segments. However, vertical shear may
be suitable for a few supercells, especially across west Texas.
Isolated large hail will be possible with any more discrete cells
that develop and can be maintained ahead of the front.

..Leitman.. 09/21/2024

$$