Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Oct 24 2024 19:48:40 ACUS01 KWNS 241948 SWODY1 SPC AC 241946 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Thu Oct 24 2024 Valid 242000Z - 251200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF EASTERN KANSAS INTO NORTHERN MISSOURI AND IOWA... ....SUMMARY... Isolated large hail (up to 1-1.75 inch diameter) and strong wind gusts (around 50-60 mph) will be possible from eastern Kansas into northern Missouri and parts of Iowa this evening into early tonight. ....20Z Update... ....Eastern Kansas into Missouri and Iowa... Recent surface analysis places the primary low over southeast SD, with a cold front extending southwestward from this low across central NE and into western KS. Additional surface cyclogenesis is still anticipated over central KS later this evening, at the intersection of the aforementioned cold front and a warm front that arcs from north-central KS eastward to MCI and even more southeastward through southwest MO. This warm front is expected to continue slowly progress northeastward, with warm and modest moist conditions advecting into eastern KS and adjacent far western MO. Thunderstorms are still expected as the cold front interacts with a modestly buoyant airmass across eastern KS and western MO. Some cellular activity is possible initially, with 35 to 45 kt of effective bulk shear supporting the potential for large hail (1 to 1.75" in diameter). Given the strong forcing along the front, any development should trend towards a linear mode quickly. The opportunity for severe will be limited by both the fast-moving front and narrow corridor of buoyancy, with severe coverage expected to remain isolated. A few isolated gusts from 50 to 60 mph are anticipated as well. Isolated hail also remains possible across southern IA, where warm-air advection should result in elevated thunderstorms amid cold mid-level temperatures and moderate vertical shear. In both of these areas, the overall severe coverage is still forecast to remain isolated, precluding the need to increase severe probabilities with this update. ...Mosier.. 10/24/2024 ..PREV DISCUSSION... /ISSUED 1124 AM CDT Thu Oct 24 2024/ ....Eastern Kansas into Missouri and Iowa... A shortwave trough over WY/CO will continue eastward across the central Plains through this evening, eventually reaching the mid MS Valley by early Friday morning. Related cyclogenesis across the central High Plains will lead to a consolidated surface low over the mid MO Valley this evening, with a cold front extending southwestward from the low across KS. A warm front should also be located over northern MO. Shallow low-level moisture, characterized by generally upper 50s to low 60s dewpoints, will be present across the warm sector from eastern KS into MO by late this afternoon. With the late arrival of large-scale ascent associated with the shortwave trough, most guidance continues to show convective initiation occurring around 00Z, beginning in eastern KS and vicinity. Up to 750-1250 J/kg of MLCAPE should be present across this area, with robust daytime heating aiding in the development of steep low-level lapse rates. Initial development may be briefly supercellular, as 30-40 kt of deep-layer shear supports updraft organization. Severe hail up to 1-1.75 inches in diameter will be possible with this initial activity, before a quick mode transition to more linear structures occurs along the cold front through the evening. Isolated strong to severe gusts (around 50-60 mph) may occur so long as thunderstorms remain surface based, before convection tends to become elevated with eastward extent into MO later this evening. Isolated hail may also occur this evening into the early overnight hours across parts of IA and northern MO, along/north of the warm front in a low-level warm advection regime. Sufficient MUCAPE and deep-layer shear should be present for robust updrafts, although it remains unclear whether supercells will be able to maintained for more than an hour or two. Given continued uncertainty in the number and longevity of surface-based supercells across eastern KS into northwest MO this evening, have opted to maintain the Marginal Risk with this update. $$ = = = 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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .