ZCZC SPCSWOMCD ALL ACUS11 KWNS 211958 SPC MCD 211958 OKZ000-TXZ000-212200- Mesoscale Discussion 2169 NWS Storm Prediction Center Norman OK 0258 PM CDT Thu Sep 21 2023 Areas affected...portions of southern Oklahoma and adjacent North Texas Concerning...Severe potential...Watch possible Valid 211958Z - 212200Z Probability of Watch Issuance...40 percent SUMMARY...Thunderstorms are forecast to increase in coverage over the next few hours, with local/limited severe threat potentially evolving. WW issuance may need to be considered in the next 1 to 2 hours. DISCUSSION...Filtered heating of a moist low-level airmass over the Oklahoma/Texas vicinity has supported afternoon destabilization, with 1000 to 2000 J/kg mixed-layer CAPE now observed. As a weak disturbance at mid levels progresses eastward across the Red River Valley area this afternoon, a cluster of thunderstorms has developed, and is currently centered over south central Oklahoma. Additional storm development is expected across this area over the next few hours. While low-level flow remains relatively weak, a belt of enhanced (around 40 kt) westerly mid-level flow associated with the aforementioned disturbance will continue to spread across this region. This will contribute to shear sufficient for organized storms, and associated potential for marginal hail/wind risk with stronger storms. Some CAMs have hinted at potential for upscale/linear growth later on, which could increase the wind potential into this evening. While storms have been slow to organize/strengthen, some recent intensification is noted over the Murray County OK vicinity. We will continue to monitor evolution of severe-weather potential across this area, along with any need for WW issuance. ..Goss/Hart.. 09/21/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SHV...TSA...FWD...OUN... LAT...LON 33489872 33919829 34499790 34819751 35129603 34739509 33889489 32889543 33039726 33489872 NNNN