ZCZC SPCSWOMCD ALL ACUS11 KWNS 231933 SPC MCD 231933 OKZ000-TXZ000-232130- Mesoscale Discussion 0227 NWS Storm Prediction Center Norman OK 0233 PM CDT Sat Mar 23 2019 Areas affected...Oklahoma into north Texas Concerning...Severe potential...Watch possible Valid 231933Z - 232130Z Probability of Watch Issuance...40 percent SUMMARY...Isolated thunderstorms may develop this afternoon across portions of Oklahoma and north Texas. These thunderstorms would be capable of gusty winds and large hail, although a brief tornado or two cannot be ruled out. DISCUSSION...Skies have mostly cleared across Oklahoma in the wake of earlier convection. Additionally, south-southeasterly winds have contributed to modest low-level moisture return as indicated by surface dewpoints in the low-to-mid 50Fs. The combination of increasing insolation, steep midlevel-lapse rates, and modest surface moisture has resulted in between 500-1000 J/kg of mixed-layer CAPE. Recent trends in the cumulus field indicates the presence of a stable layer across the region. RAP forecast soundings, and HRRR model reflectivity trends, indicate the combination of surface temperatures approaching 70F and large-scale lift will be enough to erode this stable layer during the afternoon. The result should be an increasing threat of thunderstorms capable of producing large hail and gusty winds during the late afternoon into the evening. Wind fields veer with height and would generally be supportive of updraft rotation. However, generally poor low-level moisture and weak low-level wind fields should preclude a greater tornado threat. At this time, confidence in thunderstorm coverage remains fairly low and the need for a watch is uncertain. However, trends will continue to be monitored. ..Marsh/Hart.. 03/23/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TSA...FWD...OUN... LAT...LON 32439833 36359810 36079553 32629616 32439833 NNNN