Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Aug 18 2024 20:02:25 ACUS01 KWNS 182002 SWODY1 SPC AC 182000 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Aug 18 2024 Valid 182000Z - 191200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ALONG AN AXIS FROM SOUTHEAST KANSAS INTO ARKANSAS/MISSISSIPPI...THEN EXTENDING ACROSS THE SOUTHEAST STATES INTO THE CAROLINAS AND MID ATLANTIC REGION... ....SUMMARY... Clusters of severe thunderstorms with strong/damaging winds are possible today along an axis from eastern Kansas into Arkansas/Mississippi, then extending across the southeast states into the Carolinas and Mid Atlantic region. ....20Z Update... The forecast generally remains on track, and very minor changes were made with this update. In particular, the Slight Risk was trimmed across much of northeast/eastern KS -- behind a remnant MCS now tracking southeastward across southeast KS. Large uncertainty remains regarding the evolution of these storms through the afternoon, though strong diurnal heating/increasing instability and favorable deep-layer shear could still favor an eventual increase in intensity. From the Southeast into the Mid-Atlantic, clusters of storms continue to intensify and track southeastward and east-northeastward respectively, posing a risk of damaging winds and isolated severe hail. For details, reference MCDs 1945, 1946, 1947, and Severe Thunderstorm Watches 634, 635, and 636. Farther west, thunderstorms will continue spreading northward across parts of the Great Basin, posing a risk of damaging winds. Reference MCD 1944 for more details. ...Weinman.. 08/18/2024 ..PREV DISCUSSION... /ISSUED 1121 AM CDT Sun Aug 18 2024/ ....Eastern States... A broad upper trough persists over the eastern US today, with the main baroclinic zone extending from eastern NY/PA southward into the Mid Atlantic region and western Carolinas. Pockets of strong heating and a very moist surface air mass will result in widespread moderate CAPE values ahead of the front this afternoon, where scattered thunderstorms are forecast to develop. Cyclonic flow aloft around the upper trough will be sufficient to help organize storms into multicell clusters capable of damaging wind gusts and some hail. This activity will slowly move eastward through the early evening with a continued severe threat. ....Southern States... Clear skies are present today across the southern tier of states, with dewpoints in the mid 70s yielding afternoon CAPE of 2500+ J/kg. Widely scattered thunderstorms will develop by mid-late afternoon along the western extent of the aforementioned baroclinic zone that will stretch from central GA/AL/MS then northwestward across AR. Moderately strong mid-level winds, and considerable dry air aloft will help to promote downburst winds in the strongest cores throughout this corridor. ....Eastern KS... A nocturnal MCS persists this morning over southeast NE. Most 12z CAM guidance suggests this cluster of storms diminishes, however given the mesoscale organization of the MCS, it could persist through the morning diurnal min. If that scenario occurs, conditions favor a potentially damaging wind event across parts of eastern KS through the afternoon and evening. ....UT/ID/MT... Several weak mid-level shortwave troughs are evident this morning across the northern Great Basin. These features and associated pockets of mid-level moisture will aid in the development of scattered thunderstorm development from southern UT northward into the mountains of western MT. Favorably strong southerly winds aloft will support a risk of gusty/damaging wind in the strongest cells. $$ = = = 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) .