ZCZC SPCSWOMCD ALL ACUS11 KWNS 041925 SPC MCD 041925 INZ000-ILZ000-WIZ000-IAZ000-MOZ000-042130- Mesoscale Discussion 0189 NWS Storm Prediction Center Norman OK 0125 PM CST Mon Mar 04 2024 Areas affected...Northeast Missouri to northern Illinois and southern Wisconsin Concerning...Severe potential...Watch unlikely Valid 041925Z - 042130Z Probability of Watch Issuance...20 percent SUMMARY...Additional thunderstorm development is expected along and just ahead of cold front from southern Wisconsin into eastern Iowa, northwest Illinois, and northeast Missouri in the next 1-3 hours. Thunderstorms will primarily pose a damaging wind and severe hail risk. DISCUSSION...Gradual destabilization is ongoing across portions of MO/IA/IL as temperatures climb into the low to mid 70s amid broken cloud cover and continued northward moisture return. Recent temperature/dewpoint observations are higher than anticipated by recent guidance by as much as a few degrees, suggesting that MLCIN is likely eroding slightly faster than depicted by guidance and/or mesoanalyses. Satellite imagery bears this out with slowly deepening cumulus developing from northeast MO to western IL and a recent intensification of previously anemic convection along the IA/IL border. High-res guidance suggests additional convection is likely in the next couple of hours along and ahead of the cold front, but the aforementioned observed trends hint at the potential for earlier initiation. Regardless of precise timing, initially semi-discrete cells should undergo upscale growth owing to strengthening forcing for ascent and undercutting nature of the front, as well as mean storm motion and deep-layer shear vectors oriented northeast along the boundary. Consequently, an initial hail threat should transition to a damaging wind threat threat heading into the late afternoon hours and with eastward extent. Poor boundary-normal deep-layer shear should limit overall storm organization/intensity. A low-end tornado threat may materialize across northern IL where backed low-level flow in the vicinity of the warm front may locally enhance effective SRH. However, this may be conditional on realizing at least a semi-discrete storm mode. Additionally, the northward extent of the warm sector into southern WI is uncertain given extensive cloud cover and falling temperatures north of the surface warm front. Given these concerns, watch issuance is not anticipated. ..Moore/Hart.. 03/04/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LOT...ILX...MKX...LSX...DVN...ARX...DMX...EAX... LAT...LON 41818741 41548752 41368794 40249048 40019105 39789180 39709265 39829310 40159337 40459329 40749300 40959236 41109211 41439171 43298995 43498966 43478876 42918777 42418756 41818741 NNNN