Storm Prediction Center Mesoscale Discussion 306

   Mesoscale Discussion 0306
   NWS Storm Prediction Center Norman OK
   0306 PM CDT Sun Mar 30 2025

   Areas affected...North Texas into southeast Oklahoma and southwest
   Arkansas

   Concerning...Severe potential...Watch likely 

   Valid 302006Z - 302200Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Thunderstorm development is expected along the cold front
   draped from western Arkansas into southeast Oklahoma and
   north/northeast Texas in the coming hours. The convective
   environment will likely support supercells with a large hail and
   severe wind risk. Watch issuance is expected as convective
   initiation becomes imminent.

   DISCUSSION...Forcing along the surface cold front is evident in
   visible imagery  as a narrow band of agitated cumulus draped from
   western AR into southeast OK and into northern TX. GOES day cloud
   phase imagery suggests that convective initiation is not immediately
   imminent, though temperatures warming into the low 80s with an
   influx of mid-60s dewpoints has been slowly eroding inhibition per
   recent RAP mesoanalyses. The warm/moist low-level conditions,
   coupled with 7-7.5 C/km mid-level lapse rates, are supporting MLCAPE
   values upwards of 2500 J/kg. While the strongest mid-level winds
   associated with the passing upper wave are beginning to move beyond
   the greater Texarkana region, 35-45 knot flow aloft is still
   sufficient for 40-45 knot effective bulk shear. Southwesterly winds
   in the lowest kilometer are limiting low-level helicity across TX
   and southeast OK, but is favoring somewhat straight hodographs that
   will promote splitting supercells with an attendant risk for severe
   winds and very large (2.0 to 3.0 inch) hail. Into southwest AR, more
   southerly flow within a residual cold pool from morning convection
   may allow for locally higher SRH and a somewhat higher tornado
   threat. 

   The timing of convective initiation and storm coverage remain
   uncertain. Latest high-res guidance suggests storm coverage will be
   limited to parts of northern/central TX, but surface temperatures
   are currently 2-4 F warmer than forecast by guidance, suggesting
   that modeled inhibition may be erroneously strong. Regardless, given
   the aforementioned convective environment, a severe threat will
   likely materialize if/when thunderstorms begin to develop late this
   afternoon/evening. Trends will continue to be monitored and watch
   issuance is likely as the threat becomes more imminent.

   ..Moore/Smith.. 03/30/2025

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

   ATTN...WFO...LZK...SHV...TSA...FWD...OUN...

   LAT...LON   32539536 32389595 32309638 32259680 32259711 32299735
               32379754 32469763 32629760 32859742 33149691 33609627
               34599480 34799439 34839407 34839339 34729301 34429277
               33969309 33369377 32939438 32719487 32539536 

   MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN