Mesoscale Discussion 1617
   NWS Storm Prediction Center Norman OK
   0324 PM CDT Fri Aug 28 2020

   Areas affected...Eastern Michigan

   Concerning...Severe potential...Watch unlikely 

   Valid 282024Z - 282200Z

   Probability of Watch Issuance...20 percent

   SUMMARY...A couple supercells are expected to persist into early
   evening.

   DISCUSSION...Two low-topped supercells have developed along the warm
   front in Gratiot and Saginaw counties this afternoon with moderate
   to strong mid-level rotation. The environment downstream has
   destabilized for at least a county or two which should support these
   supercells continuing. MLCAPE is only around 1000 J/kg in this area
   and mid-level lapse rates are around 6 C/km. While this typically
   would not support a hail threat, the strongly rotating nature of the
   updraft may be sufficient for some large hail. Otherwise, damaging
   winds will be the primary threat. A tornado cannot be ruled out
   given these storms are riding along the warm frontal boundary, but
   the VWP from KGRR and KDTX show weak winds in the lowest 1km which
   should mitigate the overall tornado threat. In addition, thus far,
   0.5 degree base velocity data from KGRR hasn't shown much low-level
   rotation.

   ..Bentley/Grams.. 08/28/2020

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

   ATTN...WFO...DTX...APX...GRR...

   LAT...LON   42778413 43158486 43378492 43718467 43918391 43988305
               43388219 43048239 42848317 42778413