ACUS01 KWNS 191952
SWODY1
SPC AC 191950

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0250 PM CDT Fri Apr 19 2024

Valid 192000Z - 201200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
THE SOUTHEAST...

...SUMMARY...
Sporadic strong to marginally severe storms are possible over parts
of the Southeast this afternoon into the early evening.

Little change made to the outlook at 20Z.

...Southeast...
Strong heating continues well ahead of the cold front, beneath
modest west/northwest flow aloft. Midlevel lapse rates are poor, but
sufficient instability coupled with the heated boundary layer and
sufficient flow should support a few storms capable of damaging
gusts or marginal hail with the more robust cells. Convergence near
a weak low and a zone of mid 60s F dewpoints over central NC/eastern
SC may yield the strongest cells.

See mesoscale discussion 494 for more details.

..Jewell.. 04/19/2024

.PREV DISCUSSION... /ISSUED 1126 AM CDT Fri Apr 19 2024/

...Southeast this afternoon/evening...
Late morning water-vapor imagery shows a mid-level shortwave trough
moving east across the southern Appalachians.  This feature will
reach the VA/NC coast early tonight.  Farther northwest, a closed
midlevel low will evolve into an open wave as it moves eastward over
the Great Lakes and OH Valley.  An associated surface cold front
will continue to move slowly southeastward from TX to the southern
Appalachians.  Isolated to widely scattered thunderstorms will be
possible with the disturbance over the Carolinas this afternoon. 
Other than the front pushing into portions of AL/GA, little
larger-scale forcing for ascent is expected farther southwest. 
Additional storm development will be associated with the front and
orographic lift along the spine of the Appalachians.  Overall
weak-moderate buoyancy, modest deep-layer shear and steepening
low-level lapse rates will support some potential semi-organized
storms capable of producing isolated wind damage and marginally
severe hail for a few hours this afternoon/evening.

...TX through tonight...
--No change needed to previous forecast discussion--
Weak upslope flow along a slow moving cold front will favor
thunderstorm development over the east slopes of the Sierra Madre
Oriental/Sierra del Burro this afternoon, with the potential for a
couple of supercells.  However, it is not clear that storm motions
will bring the convection across the Rio Grande, and lingering
convective inhibition suggests storms will likely weaken if they
manage to cross the border.  Later tonight in northwest TX, elevated
convection will likely develop atop the frontal surface, in a warm
advection regime downstream from a weak shortwave trough over AZ/NM.
Some small hail may occur given lingering steep midlevel lapse rates
and modest cloud-layer shear, but the potential for severe hail
appears too low to warrant an outlook area.

$$