Mesoscale Discussion 1684
   NWS Storm Prediction Center Norman OK
   0714 PM CDT Mon Sep 07 2020

   Areas affected...Northern Missouri...Southern Iowa...Central IL

   Concerning...Severe potential...Watch unlikely 

   Valid 080014Z - 080215Z

   Probability of Watch Issuance...5 percent

   SUMMARY...Thunderstorms are expected to develop and spread east
   across northern Missouri/southern Iowa into central Illinois over
   the next few hours. Hail may be noted in the strongest cores.

   DISCUSSION...Weak mid-level height falls are spreading across the
   central Plains this evening ahead of a deeper trough that is digging
   south across the Rockies. While any appreciable mid-level
   disturbance is not forecast to eject across the mid MS Valley
   tonight, LLJ will increase across KS into northeast MO over the next
   few hours. Latest surface analysis suggests a well-defined surface
   front remains draped across central IL/northern MO and this boundary
   should move little through the night. However, sustained low-level
   warm advection will become increasingly favorable for elevated
   convection north of the wind shift. Forecast RAP soundings suggest
   LFCs will be between 750-800mb with ample buoyancy for robust
   updrafts. Latest satellite/radar imagery suggest scattered showers
   are now deepening along the MO/IA border and lightning will increase
   with this activity soon. Hail is the primary risk, some of which
   could exceed one inch. However, confidence is not high that hail
   sizes will warrant a severe thunderstorm watch. Will continue to
   monitor this region.

   ..Darrow/Edwards.. 09/08/2020

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

   ATTN...WFO...ILX...LSX...DVN...DMX...EAX...

   LAT...LON   41209382 41179068 40289003 40239392 41209382