Storm Prediction Center Mesoscale Discussion 481

   Mesoscale Discussion 0481
   NWS Storm Prediction Center Norman OK
   0526 AM CDT Sat Apr 19 2025

   Areas affected...Southeast Missouri...Southern Illinois...Southwest
   Indiana

   Concerning...Severe potential...Watch possible 

   Valid 191026Z - 191300Z

   Probability of Watch Issuance...60 percent

   SUMMARY...A threat for severe wind gusts will likely continue across
   parts of southeast Missouri, and may affect parts of southern
   Illinois and southwest Indiana later this morning. New watch
   issuance may be needed.

   DISCUSSION...The latest high-resolution radar imagery from St. Louis
   shows a short bowing line segment moving through southeast Missouri.
   The line segment is located near a boundary along the western edge
   of a moist airmass, where the RAP has MUCAPE around 1000 J/kg. The
   line is also located near the entrance region of an 80 to 90 knot
   mid-level speed max. This feature is contributing to lift and strong
   deep-layer shear. RAP forecast soundings in southeast Missouri have
   0-6 km shear near 70 knots, with 40 knots of flow about 700 meters
   above ground level. This, combined with a forward speed of about 50
   knots, suggest the bowing line segment will be associated with
   severe gusts. As the line moves northeastward across southeast
   Missouri and into southern Illinois, wind gusts exceeding 70 mph
   will be possible. If the line can intensify, then watch issuance
   would become necessary.

   ..Broyles/Gleason.. 04/19/2025

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

   ATTN...WFO...LMK...IND...PAH...ILX...LSX...SGF...

   LAT...LON   37949095 37639118 37409116 37199101 37089068 37109040
               37378927 38038745 38338678 38798646 39268665 39568690
               39668714 39648768 39488818 39208875 38419026 37949095 

   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN