Storm Prediction Center Mesoscale Discussion 2298

   Mesoscale Discussion 2298
   NWS Storm Prediction Center Norman OK
   0933 AM CST Sat Dec 28 2024

   Areas affected...portions of eastern Texas into Louisiana and
   southwestern Mississippi

   Concerning...Tornado Watch 718...

   Valid 281533Z - 281730Z

   The severe weather threat for Tornado Watch 718 continues.

   SUMMARY...The severe threat continues across Tornado Watch 718.
   Damaging gusts, large hail, and a couple of tornadoes may occur
   through the remainder of the morning.

   DISCUSSION...Recent MRMS mosaic radar imagery depicts a decreasing
   trend in convective coverage and intensity across portions of the
   Lower MS Valley along the warm front, possibly due to localized
   subsidence preceding a rapidly approaching mid-level trough/speed
   max. Even so, the boundary layer continues to further destabilize
   with the onset of diurnal heating. South of the warm front,
   temperatures are rising over 70 F amid 68-70 F dewpoints over some
   locales, contributing to 1500-2000 J/kg MLCAPE per 15Z mesoanalysis.
   The low-level jet axis and upper-level speed maxima are still
   located over portions of eastern TX, contributing to modest
   warm-sector hodographs. When factoring in potential large-scale
   subsidence, the severe threat may remain on the more isolated end of
   the spectrum over the next few hours.

   However, the mid-level trough should rapidly translate eastward,
   resulting in increased forcing for ascent, as well as a further
   increase in both deep-layer and low-level shear past late morning.
   The increase in forcing and shear will coincide with an optimally
   buoyant boundary layer to support a more concentrated severe threat
   by afternoon, including the potential for strong tornadoes.
   Currently, a confluence band resides across the easternmost counties
   of Texas, which may serve as the impetus for potential supercell
   development later this afternoon. Any supercells that can mature and
   sustain themselves within this band will have the best chance for
   strong tornadoes. Otherwise, all severe hazards may accompany an
   approaching QLCS that is in the process of developing across central
   TX.

   ..Squitieri.. 12/28/2024

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...JAN...LIX...LCH...SHV...HGX...FWD...

   LAT...LON   32289491 32499254 32369033 31598953 30848935 30268968
               30099113 30119270 30089370 30269451 30539503 30919553
               31289554 31949539 32289491