Mesoscale Discussion 0933
   NWS Storm Prediction Center Norman OK
   0339 PM CDT Thu Jun 18 2020

   Areas affected...northwest IA...southern MN

   Concerning...Severe potential...Watch possible 

   Valid 182039Z - 182215Z

   Probability of Watch Issuance...40 percent

   SUMMARY...A couple of strong to locally severe gusts are possible
   this afternoon into the early evening.  Marginally severe hail
   (diameter around 1 inch) is possible with the stronger storms.  A
   severe thunderstorm watch will probably not be needed but convective
   trends will be monitored in the short-term.

   DISCUSSION...Visible-satellite imagery shows thunderstorms develop
   across southwest MN as they move east into a destabilizing airmass
   over southern MN.  Temperatures have warmed into the lower 80s deg F
   with dewpoints in the mid 60s.  KMPX VAD shows around 25-kt 0-6km
   shear with weaker flow observed farther south at the KDMX VAD.  As a
   result of the magnitude of flow within a marginal/moderately
   unstable boundary layer, the preferred storm mode will be multicells
   within bands or propagating on outflow where the flow is weaker
   (i.e., western/north-central IA).  A couple of strong to locally
   severe downbursts will be capable of gusts in the 50-60 mph range.

   ..Smith/Guyer.. 06/18/2020

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

   ATTN...WFO...MPX...DMX...FSD...OAX...

   LAT...LON   42129621 43579574 44779458 45179331 44709288 42269437
               41779502 42129621