Mesoscale Discussion 1848
   NWS Storm Prediction Center Norman OK
   0502 PM CDT Sat Aug 05 2023

   Areas affected...Northwestern Iowa into adjacent areas of South
   Dakota and Nebraska

   Concerning...Tornado Watch 589...

   Valid 052202Z - 060000Z

   The severe weather threat for Tornado Watch 589 continues.

   SUMMARY...The threat for a tornado or two continues across
   northwestern Iowa into adjacent areas of southeast South Dakota and
   northwest Nebraska.

   DISCUSSION...Thunderstorm activity over the mid-Missouri River
   Valley continues to be focused along a surface warm front noted in
   recent surface analysis. By most metrics, this convective intensity
   has been muted with modest reflectivity values, transient lightning
   pulses, and somewhat warm cloud top temperatures. However, cells
   continue to take on supercellular characteristics early on in their
   life cycle, and weak low to mid-level rotation is noted in KFSD
   velocity data. KFSD VWP observations well north of the warm front
   show 0-1 km SRH values near 200 m2/s2 where surface winds are
   easterly. This is likely an overestimate for the what cells are
   experiencing along the warm front (where winds are out of the
   southeast). But taken in context of the velocity trends suggests
   that SRH is likely sufficient to maintain a tornado threat for more
   robust cells that can become established prior to moving into a more
   stable air mass north/northeast of the warm front.

   ..Moore.. 08/05/2023

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

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

   LAT...LON   41489551 41949588 42389633 42729702 43049721 43339697
               43289606 42879521 42589469 42119433 41599426 41289444
               41189467 41159502 41239529 41489551