Mesoscale Discussion 1456
   NWS Storm Prediction Center Norman OK
   0228 PM CDT Mon Aug 10 2020

   Areas affected...Portions of southern Lower MI into northern/central
   IN and far northwestern OH

   Concerning...Severe potential...Severe Thunderstorm Watch likely 

   Valid 101928Z - 102100Z

   Probability of Watch Issuance...95 percent

   SUMMARY...A substantial severe wind threat will likely increase this
   afternoon across parts of southern Lower Michigan and into
   northern/central Indiana with a line of storms moving quickly
   eastward. A Severe Thunderstorm Watch will be needed.

   DISCUSSION...A bow echo will continue moving rapidly eastward across
   northern IL and far southern WI this afternoon while producing
   widespread damaging winds of 70-100 mph. The airmass across southern
   Lower MI and northern/central IN continues to destabilize this
   afternoon, with surface temperatures having warmed into the mid to
   upper 80s, and surface dewpoints in the low to mid 70s. Steeper
   mid-level lapse rates observed on the 18Z ILX sounding have likely
   spread over at least the western portions of southwestern MI and
   western IN. Resultant MLCAPE of 2000-3500 J/kg and around 25-30 kt
   of effective bulk shear will likely support the maintenance of the
   severe bow echo as it moved eastward across these areas this
   afternoon and early evening. Severe wind gusts, some 75+ mph, will
   likely produce numerous to widespread damaging winds, and a tornado
   or two cannot be ruled out with circulations embedded within the
   line. This substantial severe wind risk is expected to increase
   within the next couple of hours, and a Severe Thunderstorm Watch
   will be issued to address this threat.

   ..Gleason/Grams.. 08/10/2020

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

   ATTN...WFO...IWX...GRR...IND...

   LAT...LON   40418705 40928687 41818688 43008706 43078441 41688442
               40748484 40138526 40138679 40418705