Mesoscale Discussion 1504
   NWS Storm Prediction Center Norman OK
   0329 PM CDT Wed Jul 17 2019

   Areas affected...far eastern ND into northwest MN and far northeast
   SD

   Concerning...Severe potential...Watch possible 

   Valid 172029Z - 172230Z

   Probability of Watch Issuance...60 percent

   SUMMARY...Strong to severe thunderstorms are expected to increase in
   coverage late this afternoon and evening. A watch may be needed for
   portions of northwest MN into far eastern ND and northeast SD.

   DISCUSSION...A CU field across the MCD area has progressively become
   more agitated this afternoon as strong heating has resulted in
   1500-2000 J/kg MLCAPE to the south and west of a northward advancing
   warm front. A 19z RAOB from ABR indicated some subsidence may have
   been impacting the region on the back side of a shortwave
   impulse/MCV that tracked across the region early this morning. Based
   on latest water vapor imagery, moisture appears to be moving back
   toward the region ahead of the next shortwave impulse. As ascent
   increases over the MCD area by early evening, additional
   thunderstorm development is expected. This development could occur
   in the vicinity of the warm front across northern MN and/or in a
   zone of low level convergence along a surface trough extending
   across western MN to a weak surface low over eastern SD. Any storms
   that form in this area will have a moderately unstable environment
   and effective shear of 35-45 kt to work with, allowing for organized
   storms clusters capable of damaging wind and hail. Additionally,
   backed low level easterly winds in the vicinity of the warm front
   and the surface trough are enhancing low level SRH to around 150-250
   m2/s2 across portions of the region. This could result in a tornado
   threat with any stronger, more discrete cells that can develop.
   Trends will be monitored and a watch may be needed for portions of
   the MCD area in the next 1-2 hours.

   ..Leitman/Guyer.. 07/17/2019

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

   ATTN...WFO...DLH...MPX...FGF...ABR...BIS...

   LAT...LON   49389469 48449382 47449335 45879445 44959572 44909683
               45139767 45649814 47049813 48899757 49149627 49149533
               49419532 49389469