SPC AC 051943

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0243 PM CDT Wed Apr 05 2023

   Valid 052000Z - 061200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM WESTERN
   TENNESSEE INTO THE OHIO RIVER VALLEY...

   ...SUMMARY...
   Severe thunderstorm winds, large hail and a few tornadoes are
   expected today from the Great Lakes to parts of east Texas and
   Louisiana.

   ...Mid-MS River Valley to the Great Lakes region...
   Broken convective line segments continue to migrate east/northeast
   from western TN into the greater OH River Valley region. Damaging
   winds continue to be noted with the stronger segments of the line
   and/or embedded cells, and broken cloud cover ahead of the line
   coupled with low 60s dewpoints continues to support MLCAPE values
   near 1000 J/kg. Regional VWPs are also sampling 50+ flow within the
   lowest 1-2 km, north of the OH River, which suggests that damaging
   winds will remain possible with more organized segments. 

   ...Lower MS River Valley...
   Further south, an uptick in convective intensity is noted as the
   broken line along/ahead of the cold front impinges on a more
   unstable air mass (MLCAPE near 2000-2500 J/kg). The threat for
   severe wind/hail, and perhaps a tornado, will continue through the
   evening hours - see MCD #488 for additional details.

   ..Moore/Gleason.. 04/05/2023

   .PREV DISCUSSION... /ISSUED 1121 AM CDT Wed Apr 05 2023/

   ...Great Lakes into Lower MS Valley today...
   A long band of broken convection extends along/ahead of a cold front
   from southern Lower MI into parts of IN/IL/MO/AR/TX.  This line will
   progress eastward today across much of the OH/TN Valleys.  Ample low
   level moisture and strong winds aloft will maintain a risk of bowing
   structures and associated risk of damaging wind gusts across the
   region.  A few cells along or ahead of the line could also organize
   into supercells, posing a risk of tornadoes.  Considerable clouds,
   lessening midlevel lapse rates, and shorter-term convective trends
   are decreasing the confidence of a more widespread damaging wind
   event, but there is sufficient concern of re-intensification this
   afternoon to maintain the ENH risk and associated 30% severe wind
   probabilities in some areas.  

   ...TX/LA/MS/TN/AL tonight...
   Several weak shortwave troughs are rotating through the base of the
   upper trough, resulting in increasing large scale forcing for ascent
   by evening over parts of east TX/LA.  This will result in scattered
   thunderstorms that spread eastward into northern MS, west TN, and
   northwest AL.  Low-level winds will not be particularly strong in
   this area, and many of the storms will be on the north side of the
   stalled front.  Nevertheless, a few of the storms may pose a risk of
   large hail and gusty winds.

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