SPC AC 131947

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0247 PM CDT Mon May 13 2024

   Valid 132000Z - 141200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF
   SOUTHEASTERN TEXAS INTO SOUTHERN LOUISIANA...

   ...SUMMARY...
   Severe thunderstorms are expected through tonight from south central
   and southeast Texas across southern Louisiana, as well as the
   Florida Panhandle. The potential exists for multiple corridors of
   significant wind gusts, very large hail, and a few tornadoes.

   No major changes to the existing outlook at 20Z. 

   Scattered severe storms are currently threatening parts of the FL
   Panhandle, and over much of south-central into southeastern TX. A
   general west-east corridor of severe potential will remain from TX
   eastward along the northern Gulf Coast through tomorrow morning,
   with episodes of severe wind, hail, and a few tornadoes. Existing
   outflows have stabilized parts of the region, but some air mass
   recovery is possible overnight ahead of progressive storm clusters
   or MCSs.

   For more information see mesoscale discussion 768.

   ..Jewell.. 05/13/2024

   .PREV DISCUSSION... /ISSUED 1128 AM CDT Mon May 13 2024/

   ...Northeast Gulf coast today...
   An MCS with embedded bowing segments is ongoing across the western
   FL Panhandle, with a history of measured severe gusts in the 54-71
   kt range this morning.  This convective system will likely persist
   while moving east-southeastward through the afternoon, along and
   immediately north of a surface warm front near the coast.  Damaging
   winds will be the main threat, though embedded circulations could
   produce a couple of tornadoes.

   ...South central TX to southern LA through tonight...
   A cluster of supercells formed this morning and is approaching areas
   near and south of San Antonio as of 16z.  Extreme buoyancy (MUCAPE
   of 4000-6000 J/kg), steep midlevel lapse rates and strong deep-layer
   vertical shear/long hodographs will favor very large hail near 3
   inches in diameter as the primary threat through early afternoon. 
   Some upscale growth in this convection is likely through the
   afternoon, as the storms spread generally eastward along a stalled
   front across Houston and Lake Charles, with a continued large hail
   threat and an increase in the potential for damaging winds of 60-80
   mph.  The storms could persist into the overnight hours while moving
   across southern LA, along the outflow-reinforced boundary in the
   wake of the ongoing storms over the FL Panhandle.  Areas northeast
   of this outflow boundary have been largely overturned into MS/AL,
   with limited potential for destabilization prior to arrival of the
   storms from the west.

   ...Northeast TX/northern LA to AR/MO through early tonight...
   The primary midlevel trough will move eastward from KS/OK to MO/AR
   through this evening.  Lingering moisture/lapse rates to the north
   of the Gulf coast convection will be sufficient for at least a
   low-end hail/wind threat with convection this afternoon/evening
   along/east of a weak cold front and in the zone of ascent preceding
   the midlevel trough.  The eastward extent of any severe threat
   tonight will depend on recovery to the north of ongoing/expected
   convection near the Gulf coast, which is low confidence.

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