Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Jun 28 2023 06:00:41 ACUS01 KWNS 280600 SWODY1 SPC AC 280559 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Wed Jun 28 2023 Valid 281200Z - 291200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE UPPER MISSISSIPPI VALLEY AREA... ....SUMMARY... A relative concentration of severe risk may evolve across portions of central and northwestern Wisconsin, and adjacent portions of southeastern Minnesota and northeastern Iowa. A broader area of isolated severe storm potential is evident across much of the central/north-central portion of the country. ....Synopsis... Upper-level troughing is forecast across the western and eastern U.S. today, with these features flanking a flat ridge centered over the south-central states. At the surface, weak features are forecast to prevail, with the most pronounced feature being a baroclinic zone/warm front extending westward across Kansas and then northwestward across the central High Plains region during the afternoon. ....Portions of Wisconsin, southeastern Minnesota, and far northeastern Iowa... Models forecast afternoon development of thunderstorms across the southwestern Minnesota/western Wisconsin vicinity, within a zone of warm advection ahead of a very weak surface low progged to be crossing southern Minnesota during the afternoon. Given the belt of enhanced mid-level westerlies, atop low-level southerly flow, shear favorable for organized storms is expected. As such, a few stronger storms will likely evolve with time, along with attendant risks for severe-caliber wind/hail locally. ....Portions of the northern and central Plains into the Midwest... Multiple small-scale disturbances will move westward across the northern and central U.S., with an enhanced belt of flow between the Canadian Prairie mid-level trough, and the central and southern Plains ridge. As daytime heating results in widespread destabilization from the central and northern High Plains eastward to the Upper and Middle Mississippi Valley area, isolated thunderstorms are expected to develop across a broad area. A weak cold front crossing the Dakotas will likely be a focus for development of isolated storms, a few of which could produce hail and locally strong wind gusts during the afternoon and early evening, before diminishing. A few storms are also expected to develop within upslope flow across southeastern Wyoming, and over the higher terrain of southeastern Colorado/northeastern Oklahoma. Some potential for hail/wind would exist with storms developing in either of these areas, with some increase in storm coverage expected overnight as a southerly low-level jet develops across the southern High Plains/western Kansas. Some CAM runs suggest upscale growth into one or more clusters, some of which sustain convection through the overnight hours, shifting the storms as far east as the Mid Mississippi Valley by the end of the period. However, these scenarios remain quite uncertain, hence the broad, low-probability/MRGL risk area. ...Goss.. 06/28/2023 $$ = = = 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) .