Mesoscale Discussion 0639
   NWS Storm Prediction Center Norman OK
   1128 AM CDT Wed May 04 2022

   Areas affected...Parts of southwestern/central Oklahoma into the
   Texas Big Country

   Concerning...Severe potential...Watch likely 

   Valid 041628Z - 041900Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Increasing thunderstorm development, including a few
   supercells, appears possible as early as 1-4 PM CDT.  These will
   pose a risk for large hail, and perhaps a couple of tornadoes.

   DISCUSSION...Preceding the large-scale mid-level troughing within
   the mid-latitude westerlies across the Rockies, a much more subtle
   short wave impulse of subtropical eastern Pacific origin is evident
   satellite imagery  progressing across the Texas South Plains into
   Big Country vicinity.  It appears that increasingly divergent upper
   flow to the north and east of this feature will contribute to
   strengthening large-scale ascent, aided by lower/mid tropospheric
   warm advection.  This may generally focus along a 30 kt southerly
   850 mb jet, along which substantive low-level moistening is
   underway, beneath steep mid-level lapse rates associated with
   elevated mixed-layer air.

   The northern edge of the plume of warmer air aloft is currently near
   the Red River, but latest Rapid Refresh suggest that large-scale
   ascent and boundary-layer warming will erode inhibition across the
   Texas Big Country, as far south as the Brownwood vicinity.  Across
   northwest Texas into the Interstate 44 through I-35 corridors of
   southwestern Oklahoma, the boundary-layer remains potentially cool
   and stable, with low cloud cover slowing insolation to the north of
   the Red River.

   The extent of boundary-layer destabilization possible across
   southwest Oklahoma prior to the onset of thunderstorm initiation
   remains unclear.  However, moisture return above the surface-based
   layer appears sufficient for most unstable CAPE in excess of 2000
   J/kg.  Given at least elevated destabilization, it seems probable
   that the large-scale forcing for ascent will contribute to
   increasing thunderstorm development as early as the 18-21Z time
   frame.  As this occurs, low-level and deep-layer shear are expected
   to become increasing conducive to supercells conducive to large
   hail.  Where the boundary-layer is able to destabilize (most likely
   across parts of northwest Texas into south central Oklahoma) a
   couple of tornadoes are possible.

   ..Kerr/Smith.. 05/04/2022

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

   ATTN...WFO...FWD...OUN...SJT...

   LAT...LON   34309946 35299895 35529725 34439696 32979760 31159915
               31770007 33129964 34309946