Mesoscale Discussion 1813
   NWS Storm Prediction Center Norman OK
   0747 AM CST Wed Nov 25 2020

   Areas affected...Louisiana...Southwest Mississippi

   Concerning...Severe potential...Watch unlikely 

   Valid 251347Z - 251545Z

   Probability of Watch Issuance...20 percent

   SUMMARY...A marginal wind damage and tornado threat will exist this
   morning across the lower Mississippi Valley. The threat is expected
   to be too isolated to warrant weather watch issuance.

   DISCUSSION...The latest mosaic radar imagery shows a line of
   thunderstorms from just west of Jackson, Mississippi extending
   southwestward into central and southwestern Louisiana. This line of
   storms is located along an axis of low-level moisture where surface
   dewpoints are in the mid to upper 60s F. Despite the low-level
   moisture, the RAP is only showing MLCAPE in the 500 to 800 J/kg
   range ahead of the line. On water vapor imagery, an upper-level
   trough is located in the Arklatex with a lead shortwave trough over
   the lower Mississippi Valley. A band of strong large-scale ascent
   associated with this feature will help sustain the line of storm
   this morning. In addition, the observed sounding at Jackson,
   Mississippi has veering winds with height in the low to mid-levels
   with strong speed shear in the boundary layer. This profile combined
   with the weak instability will be sufficient for a marginal severe
   threat this morning. Strong wind gusts will be possible along the
   more organized parts of the line. The low-level shear profile should
   also support a marginal tornado threat.

   ..Broyles/Guyer.. 11/25/2020

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

   ATTN...WFO...JAN...LIX...LCH...

   LAT...LON   31359119 30799211 29979301 29579335 29369331 29309284
               29229232 29139165 29649075 30648999 31668989 31929032
               31359119