Mesoscale Discussion 1742
   NWS Storm Prediction Center Norman OK
   0650 PM CDT Sun Oct 11 2020

   Areas affected...the east central and northern Plains into the upper
   Midwest

   Concerning...Severe Thunderstorm Watch 500...

   Valid 112350Z - 120145Z

   The severe weather threat for Severe Thunderstorm Watch 500
   continues.

   SUMMARY...The threat for severe wind and hail will continue across
   WW 500 for the next 1-2 hours, especially across southeast South
   Dakota, eastern Nebraska, and adjacent areas of Iowa and Minnesota.
   A transition to primarily a wind threat is expected heading into the
   late evening.

   DISCUSSION...Thunderstorm coverage continues to increase from
   northwest MN southward into eastern NE as an east/southeast surging
   cold front begins to overtake the leading surface trough that has
   acted as the focus for initial convection. Deep layer flow
   orientated along this boundary has lead to largely broken line
   segments and transient discrete modes across the eastern Dakotas and
   west/southwest MN. Storm interactions and a narrow axis of
   instability has largely limited the severe potential thus far, and
   will likely continue to do so into the late evening hours. However,
   a brief severe wind, and perhaps severe hail, threat will remain
   possible with any stronger convection that can remain organized as
   storms moves into central MN where effective bulk shear is slightly
   stronger due to backed low-level flow in the vicinity of a diffuse
   surface warm front.

   Further south into the SD/NE/IA/MN region, a stronger zonal
   component to upper-level winds has allowed for more persistent
   discrete modes. Effective bulk shear values on the order of 30-40
   knots will continue to favor supercellular characteristics and
   support the potential for severe hail and strong winds in the near
   term. Eventual upscale growth into linear modes (and an associated
   increase in severe wind potential) is still expected as the cold
   front catches up with the primary convective line through the
   evening.

   ..Moore/Dial.. 10/11/2020

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

   ATTN...WFO...MPX...DMX...FGF...FSD...OAX...ABR...GID...

   LAT...LON   46239670 46549611 46359541 45309477 44469478 43149499
               41929540 41249584 41029672 40979727 41059772 41299779
               41959748 42919708 43649691 44229682 45069677 46239670