918
ACUS02 KWNS 180615
SWODY2
SPC AC 180613

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1213 AM CST Tue Nov 18 2025

Valid 191200Z - 201200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF WEST-CENTRAL TEXAS INTO SOUTH-CENTRAL OKLAHOMA...

...SUMMARY...
Isolated severe storms are possible across parts of the southern
Plains on Wednesday evening into early Thursday.

...Southern Plains...

Southerly low-level flow beneath an upper ridge centered over the
central U.S. will transport Gulf moisture northward across TX and
OK. To the west, an upper low/trough over southern CA and northern
Baja Wednesday morning will develop eastward through the period,
with the system forecast to be over AZ and northwest Mexico by
Thursday morning. Southwesterly deep-layer flow will increase across
the southern Plains as the western upper trough ejects eastward.

However, more substantial height falls are not expected across the
Plains until after 00z, with some guidance maintaining neutral
height tendencies until closer to 06z. Furthermore, warmer midlevel
temperatures around 700 mb may maintain capping for much of the
diurnal period. Forecast soundings across multiple models show quite
a bit of spread with regards to surface-based evolution. While
large-scale ascent will likely remain muted until late in the
period, persistent warm advection and increasing vertical shear may
support isolated to scattered storm development near the stationary
surface boundary from west-central TX toward the Red River during
the evening into the overnight. Modest instability and shear may be
sufficient for isolated strong to severe storms, mainly capable of
producing hail.

...Southeast AZ/southwest NM...

Cooling aloft closer to the upper low/trough will support steep
midlevel lapse rates amid increasing midlevel moisture. This will
result in weak instability amid 40+ kt effective shear magnitudes. A
couple of stronger storms could produce small hail or gusty winds,
but overall severe potential appears limited at this time given a
relatively cool boundary-layer and weak buoyancy.

..Leitman.. 11/18/2025

$$