Mesoscale Discussion 0868
   NWS Storm Prediction Center Norman OK
   0929 AM CDT Tue May 21 2024

   Areas affected...Central/Eastern IA...Far Southwest WI...Far
   Northwest IL

   Concerning...Severe Thunderstorm Watch 275...

   Valid 211429Z - 211600Z

   The severe weather threat for Severe Thunderstorm Watch 275
   continues.

   SUMMARY...Threat for damaging gusts will continue across central and
   eastern IA for the next few hours.

   DISCUSSION...A convective line continues over central IA, with
   recent storm motion estimated to be northeastward at 40-45 kt. This
   motion takes the line into more of eastern IA between 15Z and 16Z.
   Recent surface analysis places a warm front from far southwest IA
   northeastward to south of CID and then eastward into northern IL.
   The ongoing convective line is currently north of this boundary,
   with the elevated character to this line likely contributing to the
   lack of measured surface gusts. The southwest-to-northeast
   orientation of the warm front and its somewhat slow motion north
   coupled with the predominantly northeastward motion of the line
   casts some doubt to whether or not this line will be able to evolve
   towards a more surface-based character with eastern extent. If it
   does, some trend towards stronger and more frequent gusts is
   possible. Even if the line remains elevated, the overall environment
   is expected to improve as it moves downstream, with damaging gusts
   remaining possible. 

   Additionally, given the improving environmental conditions
   anticipated, overall convective trends will be monitored for
   potential downstream watch issuance into northwest IL and southwest
   WI.

   ..Mosier.. 05/21/2024

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

   ATTN...WFO...MKX...DVN...ARX...DMX...

   LAT...LON   41669404 42109334 42329230 42679031 41559005 41009096
               40769245 40729362 41669404