Mesoscale Discussion 0700
   NWS Storm Prediction Center Norman OK
   0413 AM CDT Sun May 24 2020

   Areas affected...far southern MN...western and central IA...far
   northern MO

   Concerning...Severe potential...Watch possible 

   Valid 240913Z - 241015Z

   Probability of Watch Issuance...60 percent

   SUMMARY...A severe thunderstorm watch will be considered for much of
   western and central IA based on observational trends over the next
   hour or so.

   DISCUSSION...Radar mosaic shows a strong to locally severe squall
   line extending from far southeast SD southward into southeast NE.  A
   warm front is located from the southeast corner of IA west-northwest
   to near the SD/IA/NE border.  A 50-kt central Plains LLJ has been
   well sampled by KTWX and KOAX VAD overnight with low-level
   warm/moist advection occurring across the MO Valley.  The airmass
   south of the warm front is gradually destabilizing with surface
   dewpoints rising into the mid 60s in southwest IA.  

   An associated MCV and larger-scale shortwave trough will continue to
   progress east-northeast across portions of the mid MO Valley over
   the next several hours.  The preferential motion of the MCS will
   likely move east and bisect the warm frontal zone across western and
   central IA during the early morning.  It remains unclear whether
   severe gusts will continue into central IA to the east of severe
   thunderstorm watch 215.  The need for an additional severe
   thunderstorm watch will likely be dictated by both radar/surface
   observational trends over the next hour as the squall line
   approaches the eastern portion of the ongoing watch.  It seems the
   greatest coverage of potential severe will be mainly in IA but some
   risk could extend into adjacent parts of MN and MO.

   ..Smith.. 05/24/2020

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

   ATTN...WFO...DVN...ARX...MPX...DMX...EAX...FSD...OAX...

   LAT...LON   43539573 43839451 43449291 42339221 41269234 39979318
               40509638 41879570 43539573