Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Oct 03 2024 12:38:34 ACUS01 KWNS 031238 SWODY1 SPC AC 031236 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Thu Oct 03 2024 Valid 031300Z - 041200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... Severe thunderstorms are not expected through tonight. ....Synopsis/Discussion... In mid/upper levels, a nearly zonal northern-stream pattern will prevail either side of the Canadian border, from the Pacific Coast across the Great Lakes to New England. The main feature perturbing that belt for this period will be a strongly positively tilted trough, currently over south-central parts of SK/MB northwestward to north-central AB. This trough will amplify and pivot southeastward/ eastward across northern ON, northern MN and Lake Superior into tonight. By 12Z, the trailing part of this feature should be moving across the western U.P of MI, northern WI and central MN. A weak shortwave trough -- evident in moisture-channel imagery over eastern OR and southwestern ID -- may reach the Quad Cities area of IA/IL by 12Z tomorrow and phase with the larger trough. At the surface, 11Z analysis showed a frontal wave low over northwestern KS, with warm front eastward to west-central/ northwestern MO, and cold front across east-central CO. The low should migrate eastward through the period, reaching north-central/ northwestern MO by 12Z, with cold front trailing across southern KS, western OK and the TX South Plains, and warm front extending to east-central MO and southern IL. ....Mid/upper Mississippi Valley... Capping and meager boundary-layer moisture will inhibit convective potential today along/ahead of the front and low. However, an area of isolated to scattered elevated thunderstorms is possible overnight northeast of the low, supported by large-scale DCVA/lift ahead of the ejecting shortwave trough, and warm advection/ isentropic lift to LFC of increasingly moist parcels above the surface. Activity should be rooted in the 700-800-mb layer, amidst MUCAPE roughly 500-800 J/kg, and around 35-40 kt effective-shear magnitudes. This may support small hail, especially early in the convective cycle when cells are still at least somewhat discrete. Modes should become messier and precip more expansive fairly quickly, as inflow-layer moisture and MUCAPE only slowly increase in the immediate upstream airmass to the southwest. The overall severe threat appears too limited and conditional for an outlook at this time. ...Edwards/Dean.. 10/03/2024 $$ = = = 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) .