Mesoscale Discussion 0183
   NWS Storm Prediction Center Norman OK
   0254 AM CDT Tue Mar 16 2021

   Areas affected...Portions of AL into southern middle TN

   Concerning...Severe potential...Watch unlikely 

   Valid 160754Z - 161030Z

   Probability of Watch Issuance...20 percent

   SUMMARY...A rather isolated severe threat may continue early this
   morning. Watch issuance remains unlikely.

   DISCUSSION...Ascent associated with a weak perturbation embedded
   within mid-level southwesterly flow has encouraged an uptick in
   convective coverage across AL and southern middle TN over the past
   hour or two. A weak surface boundary is present across northern AL,
   separating mid 60s dewpoints from upper 50s farther north into
   southern middle TN. Any storms that form or persist to the north of
   this boundary will likely remain elevated, with mainly an isolated
   hail risk. Farther south into central AL along/south of the
   boundary, there should be a better potential for near-surface-based
   storms, as MLCAPE around 250-750 J/kg is likely present. Recent VWPs
   from KBMX show a veering and strengthening wind profile through
   mid-levels, although there is some weakness in the flow in roughly
   the 2-3 km AGL layer. Effective SRH in the 100-150 m2/s2 range could
   potentially support occasional low-level rotation, and a brief
   tornado cannot be ruled out. A strong wind gust and marginally
   severe hail may also occur with any vigorous updraft given 40-50 kt
   of deep-layer shear. Still, the modest large-scale forcing and weak
   instability will likely keep the overall severe threat rather
   isolated/marginal through the early morning hours as storms develop
   eastward. Therefore, watch issuance continues to appear unlikely at
   this time.

   ..Gleason/Thompson.. 03/16/2021

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

   ATTN...WFO...MRX...OHX...BMX...HUN...MOB...

   LAT...LON   32118840 34118801 34968780 35368725 35488613 35198569
               34808559 33558540 32688625 31958739 31928808 32118840