Storm Prediction Center Mesoscale Discussion 758

   Mesoscale Discussion 0758
   NWS Storm Prediction Center Norman OK
   0519 PM CDT Sun May 17 2026

   Areas affected...extreme eastern Texas Panhandle...northwest
   Oklahoma into south-central Kansas

   Concerning...Severe potential...Watch likely 

   Valid 172219Z - 180045Z

   Probability of Watch Issuance...80 percent

   SUMMARY...At least isolated supercells are possible later this
   afternoon and into the early evening. The conditional risk of very
   large damaging hail is high, along with a risk of a couple
   tornadoes. The area is being monitored for initial deep convection.

   DISCUSSION...High based convection currently exists within the
   low-level lapse rates plume west of the dryline from the TX
   Panhandle into far southwest KS where temperatures have reached 100
   F. Meanwhile, mid 90s F extend into much of northwest OK, where
   little convective inhibition remains.

   Low-level moisture is in the process of increasing from the
   southeast. GPS PWAT values around 1.25" are moving across central
   OK, while values near 1.60" are noted near the Red River. This
   suggests higher-quality boundary layer moisture will eventually
   spread northwestward into the strongly heated zone from the TX
   Panhandle into northwest OK later this afternoon into the early
   evening.

   Modified 18Z OUN sounding indicates low to mid 90s F temperatures
   are needed to remove inhibition. This will become more likely as the
   moisture spreads northwestward. Steep midlevel lapse rates over 8.0
   C/km along with about 40 kt deep-layer shear oriented west-east
   across the dryline suggest supercells with very large hail potential
   will be possible. A tornado, even strong, cannot be ruled out with
   any longer tracked supercell.

   ..Jewell/Smith.. 05/17/2026

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

   ATTN...WFO...ICT...OUN...DDC...AMA...

   LAT...LON   35080050 37289965 37879947 38379918 38419879 38259828
               37589777 37099758 36739758 36469772 36229829 35929900
               35179961 34860000 34930048 35080050 

   MOST PROBABLE PEAK TORNADO INTENSITY...100-125 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.75-4.25 IN