Mesoscale Discussion 0759
   NWS Storm Prediction Center Norman OK
   0216 PM CDT Thu May 18 2017

   Areas affected...Portions of eastern KS and western MO

   Concerning...Severe potential...Tornado Watch likely 

   Valid 181916Z - 182115Z

   Probability of Watch Issuance...80 percent

   SUMMARY...An increasing threat for all severe hazards, including
   isolated tornadoes, will likely warrant tornado watch issuance over
   the next several hours.

   DISCUSSION...Satellite trends show building cumulus along a warm
   front extending across KS into western MO as of 1915Z. The airmass
   along and south of the front is strongly unstable, with MLCAPE in
   the 2000-3500 J/kg range. As a 50+ kt southwesterly mid-level jet
   approaches this region, large-scale forcing for ascent will
   gradually increase. Low-level convergence along the front in tandem
   with the increasing large-scale ascent should be sufficient for
   convective initiation over the next several hours. Recent short-term
   model guidance is generally consistent in developing convection
   along the warm front by 21Z. Strengthening mid-level winds will
   support effective bulk shear values of 40-50 kt, and supercells
   structures appear likely.

   Although low-level flow is not forecast to be quite as strong as
   locations farther west (mainly western/central KS), backed
   easterly/northeasterly winds in the 0-1 km layer along the front
   will enhance effective SRH through the afternoon and early evening,
   and isolated tornadoes will be possible. Low-level winds are
   forecast to increase across this region by this evening as a
   low-level jet strengthens across the central/southern Plains. If
   initially discrete supercells remain the dominant storm mode into
   this evening, then the tornado threat would increase in the 00-03Z
   time frame. In addition to the isolated tornado threat, the very
   favorable thermodynamic environment and steep mid-level lapse rates
   present across this region will likely support large to very large
   hail with any supercell. Isolated damaging winds may also occur.

   ..Gleason/Goss.. 05/18/2017

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

   ATTN...WFO...EAX...TOP...ICT...

   LAT...LON   38209640 38479707 38879647 39159556 39419420 39299335
               39059292 38719326 38379414 38019602 38209640