Subj : MESO: Mesoscale Discussion 1786 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Jul 30 2023 19:25:36 ACUS11 KWNS 301925 SWOMCD SPC MCD 301925=20 SDZ000-NEZ000-WYZ000-302130- Mesoscale Discussion 1786 NWS Storm Prediction Center Norman OK 0225 PM CDT Sun Jul 30 2023 Areas affected...Black Hills Vicinity into southern South Dakota and far northern Nebraska Concerning...Severe potential...Severe Thunderstorm Watch likely=20 Valid 301925Z - 302130Z Probability of Watch Issuance...80 percent SUMMARY...Supercells capable of large/very large hail and severe wind gusts are expected in the Black Hills vicinity. Some upscale growth could occur later this afternoon with a greater risk of severe winds accompanying it. A watch is likely this afternoon for this activity. DISCUSSION...Outflow from an elevated cluster of storms in north-central/eastern South Dakota appears to have contributed to the development of a modest mesohigh. This is helped to foster increased convergence within the Black Hills. An updraft has continued to deepen over the last hour and storm initiation has recently occurred per NLDN data. With the downstream environment warming into the upper 80s to low 90s F, it appears that MLCIN has mostly eroded using a modified, observed 12Z Rapid City sounding. Steep mid-level lapse rates and 40-50 kts of effective shear will promote supercells capable of large/very large hail and severe wind gusts. Storm coverage may initially be isolated, but additional development later this afternoon is possible. Further, some upscale growth may occur as storms progress southeastward along a modest baroclinic zone. A watch is likely this afternoon for this activity. ...Wendt/Thompson.. 07/30/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!8IIxpR-foPwZRTqopj_LGOmDm1kCorXpFOwWkEDjhrcHRO9eghfiwE2N-1BFzjhIyUCCLn-UG= hh1CvUiui8W47rIlhY$ for graphic product... ATTN...WFO...FSD...ABR...LBF...UNR...CYS... LAT...LON 43640416 43790458 44150544 44560547 44830515 44850416 44430219 43929984 43599933 43129930 42869982 42670112 42890248 43080335 43400391 43640416=20 =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .