Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Oct 24 2023 19:59:37 ACUS01 KWNS 241959 SWODY1 SPC AC 241958 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Tue Oct 24 2023 Valid 242000Z - 251200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHWEST AND SOUTHERN HIGH PLAINS AS WELL AS THE UPPER MIDWEST... ....SUMMARY... Isolated severe thunderstorms capable of hail and/or wind are possible through tonight across parts of the Southwest into the southern High Plains, and over portions of the Upper Midwest. ....20z Update... Across the upper Midwest and western Great Lakes, a band of elevated supercells has produced intermittent severe hail along and north of a well defined quasi-stationary front. While storms have remained fairly strong with 500-1000 J/kg of MUCAPE and 40 kt of effective shear, the environment downstream appears less favorable for a sustained severe risk with time. Cooler conditions and multiple rounds of convection should gradually overturn the air mass weakening available buoyancy. Additional storm development along the warm advection zone to the west, and south into the warm sector across northern IA and southern WI is expected this evening. Isolated hail and damaging gusts will remain possible into tonight, especially with any sustained supercells. Across the southern High Plains and Southwest, cloud breaks ahead of the southern stream shortwave trough have allowed the unseasonably moist air mass to destabilize across parts of eastern AZ, NM and West TX. Visible imagery showed several updrafts developing off of the higher terrain of the Mexican High Plateau and Davis Mountains. Recent CAM guidance and RAP soundings suggest an environment favorable for isolated severe storms including a few supercells. Additional storm development should continue into the evening hours as the main trough and associated ascent shifts eastward. Increasingly meridional flow will favor upscale growth into one or more linear clusters. Damaging wind gusts and isolated hail will be possible with the strongest storms. Storm should persist with an isolated severe threat across West TX and the southern TX Panhandle late tonight. ...Lyons.. 10/24/2023 ..PREV DISCUSSION... /ISSUED 1129 AM CDT Tue Oct 24 2023/ ....Southeast Arizona/southern New Mexico to west Texas... Within the southern stream of a split flow regime, an upper low near Baja will continue to shift eastward over northwest Mexico through tonight. Increasing forcing for ascent and differential heating over higher terrain will influence a further increase in thunderstorms this afternoon across southeast Arizona, southern New Mexico, and far west Texas. Upwards of 500-1300 J/kg MLCAPE and ample effective shear, aided by strengthening/diffluent south-southwesterly winds aloft, will support isolated severe storms capable of hail and gusty winds. Storms are likely to further increase/linearly organize this evening as they progress east-northeastward across southeast New Mexico into west Texas, with a continued risk for locally severe wind gusts and marginally severe hail potentially continuing into the overnight. ....Upper Midwest... Bands of thunderstorms, including some strong/severe across Wisconsin, are ongoing from southern Minnesota to central Wisconsin and Lake Michigan vicinity at midday. This regime is occurring to the west of an MCV across northern Lower Michigan, and to the north of a front across the upper Mississippi Valley. Convection will continue to increase and move east-northeastward through the afternoon. This majority of this convection will be at least slightly elevated, with seemingly limited/uncertain potential for surface-based storms near/southeast of the surface front and surface low. Thus, the primary risk should be sporadic/isolated severe hail regionally, with some possibility for strong wind gusts, particularly with any storms evolving in closer proximity to the surface front. $$ = = = 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) .