ZCZC SPCSWOMCD ALL ACUS11 KWNS 052209 SPC MCD 052209 ILZ000-WIZ000-IAZ000-MNZ000-052315- Mesoscale Discussion 1830 NWS Storm Prediction Center Norman OK 0509 PM CDT Mon Aug 05 2024 Areas affected...eastern Iowa...northern Illinois...southern Wisconsin Concerning...Severe potential...Watch possible Valid 052209Z - 052315Z Probability of Watch Issuance...60 percent SUMMARY...Severe threat to increase this evening. Damaging winds, large hail, and a tornado are possible. DISCUSSION...Surface analysis shows a front extending across the upper Ohio River Valley into portions of the Midwest. Visible satellite shows cu development along this boundary in eastern Iowa and northern Illinois, with a few cells now on radar south of Chicago and north of Davenport. The environment in this region is characterized by MLCAPE around 2000-2500 J/kg and deep layer shear along and north of the boundary around 40-45 kts. The 19z sounding profile from DVN further supports this, with around 2300 J/kg MLCAPE. Shear profiles are somewhat weak in the low-levels, with around 25-50 m2/s2 0-1km SRH in surface objective analysis. However, low level shear should increase through time to around 100-200 m2/s2 per RAP forecasts. CAM guidance suggests a few supercells could develop, with potential for large hail, damaging wind, and perhaps a tornado. A watch may be needed to cover this threat for portions of this area in the next 1-2 hours. ..Thornton/Smith.. 08/05/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LOT...MKX...DVN...ARX...DMX... LAT...LON 43429220 43519112 43619009 43618941 43258800 42978748 42628719 42228731 41728765 41408790 41248838 41328934 41599001 41999155 42199232 42899275 43429220 NNNN