Mesoscale Discussion 0484
   NWS Storm Prediction Center Norman OK
   0155 PM CDT Tue Apr 28 2020

   Areas affected...southeast Kansas...eastern Oklahoma...southwest
   Missouri...northwest Arkansas

   Concerning...Severe potential...Watch likely 

   Valid 281855Z - 282130Z

   Probability of Watch Issuance...95 percent

   SUMMARY...Storms will develop by 21Z along and ahead of a cold
   front, and quickly become severe. Damaging hail, wind, and a few
   tornadoes are all possible.

   DISCUSSION...A surface trough extends from western OK northeastward
   across IA, with a low over northwest OK at 19Z. Meanwhile, a
   stronger cold front was surging across central KS, and across the
   Panhandles.

   Strong instability has developed near the surface trough, beneath
   very steep lapse rates aloft. Early and midday soundings show
   700-500 mb lapse rates to around 9 C/km, beneath modest northwest
   flow aloft. Meanwhile, southery surface winds are maintaining mid
   60s F dewpoints south of the cold front, resulting in strong
   instability. 

   Storms are likely to develop along and ahead of the surging front
   over KS, and become severe as they encounter the stronger
   instability. Large hail is likely initially, transitioning to
   damaging winds. Initial cellular activity may produce a brief
   tornado. As the storms move southward across eastern OK, access to
   greater low-level SRH may yield a few tornadoes, perhaps with cells
   in the line or brief QLCS.

   Farther west, steep low-level lapse rates exist over western OK and
   northwest TX, and this may help to eventually break the cap as the
   wind shift moves south toward I-40 later today. While a capping
   inversion does exist, the western fringe of the frontal storms will
   likely be severe, producing damaging hail and wind.

   ..Jewell/Thompson.. 04/28/2020

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

   ATTN...WFO...LZK...SGF...EAX...TSA...ICT...OUN...

   LAT...LON   34899807 35029818 35569852 36199843 36579797 37519640
               37729591 38009512 38179438 38019374 37639339 36849321
               36039348 35249418 35049464 34679579 34539696 34709788
               34899807