ZCZC SPCSWOMCD ALL ACUS11 KWNS 262131 SPC MCD 262131 SDZ000-NDZ000-NEZ000-262300- Mesoscale Discussion 1731 NWS Storm Prediction Center Norman OK 0431 PM CDT Wed Jul 26 2023 Areas affected...portions of central North Dakota...South Dakota...and Nebraska Concerning...Severe potential...Watch unlikely Valid 262131Z - 262300Z Probability of Watch Issuance...20 percent SUMMARY...A risk for isolated severe gusts/hail exists this afternoon with the stronger storms that can sustain themselves. A WW issuance is not currently anticipated. DISCUSSION...Strong boundary-layer heating and broad surface lee troughing is supporting the development of isolated, high-based supercells across the northern Plains. 100 F surface temperatures amid low 50s-60s F dewpoints (40-50 F T/Td spreads) preceding the supercells are contributing to 9+ C/km boundary-layer lapse rates. While 7-8 C/km mid-level lapse rates and 40+ kts of effective bulk shear (driven by elongated hodographs) suggest that mid-level updraft rotation and hail potential exists, the deep and hot boundary layer may promote sufficient melting of hail as well as evaporation of rain to support a severe gust threat through the remainder of the afternoon. Given the isolated nature of the storms and their severe threat, a Severe Thunderstorm Watch issuance is not currently expected. ..Squitieri/Grams.. 07/26/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FSD...ABR...GID...BIS...LBF...UNR... LAT...LON 40540075 44300160 46410163 47560055 47700001 47279933 46529886 45329848 43919845 42499860 41539886 40889919 40429954 40540075 NNNN