Storm Prediction Center Mesoscale Discussion 1552

   Mesoscale Discussion 1552
   NWS Storm Prediction Center Norman OK
   0915 PM CDT Wed Jul 08 2026

   Areas affected...Central to northeast Iowa

   Concerning...Severe Thunderstorm Watch 471...473...

   Valid 090215Z - 090415Z

   The severe weather threat for Severe Thunderstorm Watch 471, 473
   continues.

   SUMMARY...A threat for isolated hail will likely continue across
   portions of central to northeast Iowa for the next couple of hours.
   Downstream watch issuance is not expected.

   DISCUSSION...Over the past couple of hours, the cold pool associated
   with a weak convective band has continued to expand
   south/southwestward. New updrafts developing on the southern and
   western flanks of the cold pool have been quickly displaced into the
   cooler/more stable air due to the westerly mid-level flow regime.
   However, a few of these updrafts have shown periodic upticks in
   intensification up to near severe limits based on MRMS MESH and
   vertical ice data. Further southwest, new convective development is
   also noted along the outflow of an upstream decaying thunderstorm
   band. 

   In general, this activity resides within an axis of relatively
   higher MUCAPE and continues to experience the influence of weak
   frontal ascent (plus more localized ascent along the outflows) and
   broad-scale lift from a low-amplitude upper wave traversing the
   Plains. Because of these factors, continued updraft development
   appears possible over the next 1-2 hours and may continue to pose a
   threat for sporadic large hail and perhaps isolated strong/severe
   wind gusts.

   Beyond the next couple of hours, continued nocturnal stabilization
   and diminishing buoyancy with southeastward extent will likely act
   to modulate updraft intensities. The net result should be a gradual
   decline in thunderstorm intensity and further reduction of the
   severe threat. While some severe threat may linger in the near-term
   on the periphery of WW 471 and 473, downstream watch issuance is not
   expected.

   ..Moore.. 07/09/2026

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

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

   LAT...LON   42899251 42679183 42519161 42309136 42039134 41819145
               41689172 41639206 41659235 41709265 41859295 42049321
               42199349 42399396 42689408 42919398 43049362 43069317
               42899251 

   MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
   MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN