ACUS11 KWNS 072001 SWOMCD SPC MCD 071959 SDZ000-NEZ000-072200- Mesoscale Discussion 1534 NWS Storm Prediction Center Norman OK 0259 PM CDT Tue Jul 07 2026 Areas affected...Portions of western and central South Dakota...parts of far northern Nebraska Concerning...Severe potential...Watch likely Valid 071959Z - 072200Z Probability of Watch Issuance...80 percent SUMMARY...Large hail and severe winds are possible as storms develop by late afternoon/early evening. A watch will likely be needed this afternoon. DISCUSSION...Water vapor imagery shows a weak shortwave trough moving into eastern Wyoming. Lift associated with this feature is has promoted storm initiation near Chadron, NE, along the stationary boundary. Additional cumulus development has also been noted on visible satellite in central South Dakota. As surface heating continues to erode MLCIN, additional storm development is probable. Timing of development is not certain. Given current trends, greater coverage is expected by late afternoon and certainly early evening as the low-level jet increases. Mid-level lapse rates from the 18Z observed UNR sounding were 8.3 C/km decreasing to 6.7 C/km in ABR. With around 40-45 kt of effective shear, supercell structures capable of large hail (up to 2.5 in.) and severe winds will be possible. Some upscale growth could occur as the low-level jet increases during the evening. This could lead to a greater severe wind threat as convection moves east along the surface boundary. ..Wendt/Hart.. 07/07/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FSD...ABR...LBF...UNR...CYS... LAT...LON 42770087 42550258 42650316 42830328 43200338 43660372 44100389 44380365 44460283 44960012 44999941 44789854 44069855 43259981 42770087 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN