Storm Prediction Center Mesoscale Discussion 255

   Mesoscale Discussion 0255
   NWS Storm Prediction Center Norman OK
   0445 PM CDT Sun Mar 23 2025

   Areas affected...portions of the lower MS Valley into northwest AL

   Concerning...Severe potential...Watch likely 

   Valid 232145Z - 232245Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Scattered thunderstorms capable of hail and damaging gusts
   are becoming more likely this afternoon/evening. A few supercells
   may also favor some tornado a risk. A WW is likely needed.

   DISCUSSION...As of 2140 UTC, regional visible and radar imagery
   showed initial convective updrafts were steadily deepening over
   parts of the lower MS Valley ahead of a slow moving cold front.
   Ongoing within a broad and weakly forced warm air advection regime,
   scattered thunderstorm development appears likely over the next
   couple of hours. Surface temperatures in the low 80s and dewpoints
   in the low to middle 60s F are supporting 2000-2500 J/kg of MLCAPE
   with relatively steep low and mid-level lapse rates. Deep-layer
   shear around 35-40 kt will gradually strengthen along with the
   low-level jet this evening. This will favor a mixed convective mode
   with bowing segments and few supercells likely. 

   Large hail and damaging winds appear to be the most relevant threats
   initially given the steep lapse rates and fairly large buoyancy.
   Some tornado risk may evolve if more dominant supercells or bowing
   segments emerge with slightly stronger low-level shear this evening.
   Storms may eventually merge with additional connection developing
   closer to the front, as indicated by some hi-res guidance. This
   would favor a greater risk for damaging winds or a brief tornado as
   a loose line or cluster develops with eastward extent. Given the
   steady increase in convection and the potential for severe wind and
   hail, a watch appears likely soon.

   ..Lyons/Gleason.. 03/23/2025

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

   ATTN...WFO...BMX...HUN...MEG...JAN...

   LAT...LON   31619018 31759128 32209182 32599187 33029183 33759079
               34208919 34728777 34608751 33108801 32028922 31768985
               31619018