Storm Prediction Center Mesoscale Discussion 833


   Mesoscale Discussion 0833
   NWS Storm Prediction Center Norman OK
   0218 AM CDT Sat May 17 2025

   Areas affected...northern Georgia northeast into southern Virginia

   Concerning...Severe potential...Watch possible 

   Valid 170718Z - 170845Z

   Probability of Watch Issuance...60 percent

   SUMMARY...A long-lived thunderstorm complex continues to move south
   and east this morning. Strong thunderstorm winds, hail, and a
   tornado or two remain possible with the strongest thunderstorm
   cores. A new watch or watches may be needed downstream from existing
   watches.

   DISCUSSION...A long-lived linear MCS continues to move south and
   east this morning across the region with more isolated/cellular
   convection develop ahead of the line. This line has a history of
   producing wind damage across portions of east Tennessee.

   The portion of the line across Tennessee, Virginia, and North
   Carolina appears to be moving through a minimum in favorability for
   severe thunderstorms. Here MUCAPE is only about 1000 J/KG, although
   deep-layer shear remains more than sufficient at greater than 50
   knots. Ahead of this portion of the line, the environment actually
   improves to the east as MUCAPE increases to nearly 2500 J/kg across
   central Virginia.

   Given the increasingly favorable-for-severe environment downstream
   of the existing line, a new watch may become necessary across
   western North Carolina and southern Virginia.

   Farther southwest, more uncertainty for severe potential exists.
   Convective cells have become oriented more parallel to the
   large-scale shear vectors. This has resulted in less downward
   momentum transfer and slowed the advancement of the line. As the
   multitude of individual cells within the linear MCS continue to
   interfere with one another, robust thunderstorm updrafts capable of
   producing large hail and damaging winds has been limited. Despite
   this, the overall large-scale environment will remain conducive for
   episodic severe potential and thus the area will also be monitored
   for watch potential.

   ..Marsh/Bunting.. 05/17/2025

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

   ATTN...WFO...RNK...GSP...MRX...FFC...

   LAT...LON   37268118 37147926 36238050 34918282 34318520 35528546
               36368286 37268118 

   MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN

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