SPC MD 933

MD 0933 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF SOUTHEASTERN MISSOURI....SOUTHERN ILLINOIS AND ADJACENT SOUTHWESTERN INDIANA...WESTERN KENTUCKY AND ADJACENT NORTHWESTERN TENNESSEE Mesoscale Discussion 0933 NWS Storm Prediction Center Norman OK 0601 AM CDT Mon Jun 01 2026 Areas affected...parts of southeastern Missouri....southern Illinois and adjacent southwestern Indiana...western Kentucky and adjacent northwestern Tennessee Concerning...Severe potential...Watch unlikely Valid 011101Z - 011330Z Probability of Watch Issuance...20 percent SUMMARY...Thunderstorm development probably will be maintained southeastward across areas near and northeast of the Mississippi/Ohio River confluence through 8-10 AM CDT, but with more limited potential for severe wind and hail. While a new watch is not currently anticipated in the near term, trends will continue to be monitored. DISCUSSION...Vigorous thunderstorm development persists with a bit further upscale growth. It has not yet become particularly organized, but a meso beta scale convective vortex may be developing near/west-northwest of St. Louis. Coupled with continuing broad lower/mid-tropospheric warm advection, this may maintain southeastward development of convection across the lower Ohio Valley, near and northeast of its confluence with the Mississippi River, through 14-15Z. As this occurs, it does appear that moist inflow on its western flank will become at least a bit more stable. Furthermore, downstream of convection, the boundary layer is, at least initially, a bit cooler/drier and more stable across southeastern Missouri into the lower Ohio Valley, which seems likely to limit the strength of associated surface gusts in descending convective outflow. ..Kerr/Hart.. 06/01/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OHX...PAH...MEG...LSX... LAT...LON 38279027 38878986 38278813 37158697 36168872 36818983 37869136 38279027 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH Read more