Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Aug 17 2024 17:31:41 ACUS02 KWNS 171731 SWODY2 SPC AC 171729 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE DEEP SOUTH TO THE MID-ATLANTIC STATES... ....SUMMARY... Scattered wind damage will be possible from the Mid-Atlantic States to the Deep South from mid-afternoon to early evening on Sunday. ....Deep South to the Mid-Atlantic States... A persistent, slow-moving mid/upper trough from the eastern Great Lakes to the southern Appalachians should amplify slightly as a mid/upper jetlet digs into the basal portion of the trough. This will result in the belt of enhanced northwesterly to west-southwesterly mid-level flow becoming centered across the Southeast by Sunday afternoon. Occluded surface cyclone should drift east across southern ON into western NY. An arcing cold front will largely extend south across the Mid-Atlantic to Southeast before trailing westward over the Deep South to Lower MS Valley. Hot temperatures from 95-103 F are expected at peak heating along the trailing portion of the front west of the Carolinas. This should yield moderate to large buoyancy amid moderate northwesterly deep-layer shear. Isolated to scattered thunderstorm development is anticipated towards late afternoon along the weakly convergent front. While severe hail is possible, the rather warm thermodynamic profile should largely support a primary threat of scattered damaging winds from strong to severe wind gusts. Confidence is below average in where south-southeast moving clusters should develop, so have maintained a broad level 2-SLGT risk despite some embedded areas likely not having thunder occur. Convective coverage may become widespread across parts of the Lower Mid-Atlantic States where larger-scale ascent with stronger low-level convergence is expected. Although deep-layer shear should be comparatively weaker along with poor mid-level lapse rates, rich boundary-layer moisture and adequate heating should be sufficient for a scattered wind damage threat. Strong to localized severe gusts with slow, eastward-moving multicell clusters will be possible, and the level 2-SLGT risk has been expanded north. ....Central Plains and the Black Hills... A mid/upper ridge will remain anchored across the High Plains between the trough over the East and a trough along the Pacific Northwest coast. A plume of rich boundary-layer moisture will persist from the Ozarks into the central High Plains within a modest northwesterly mid-level flow regime. At least isolated elevated convection, driven by low-level warm theta-e advection, should be ongoing at 12Z Sunday across central parts of NE/SD. There's a low probability that this activity could strengthen during the day with a primary threat of isolated severe hail as it gradually sinks southward, or additional isolated surface-based storms may form within the lingering differential heating zone later in the afternoon. Isolated high-based storms may also develop from the Black Hills to eastern CO and spread east-southeast. Localized severe wind/hail will be possible through about dusk. ....Eastern Great Basin to central MT... Isolated to scattered afternoon thunderstorms are expected along the western periphery of the buoyancy plume across the Intermountain West and Rockies. Mid-level southwesterlies will be modestly greater across the eastern Great Basin with peripheral influence of the northward-moving shortwave trough along the Pacific Northwest coast. This should yield moderate storm motions and a threat for sporadic severe gusts with high-based convection. A similar steep lapse rate environment will extend farther north into central MT. However, closer proximity to the mid-level ridge should yield weak deep-layer shear. More pulse-type thunderstorms are expected here, but a threat for dry microbursts capable of strong gusts will be possible. ...Grams.. 08/17/2024 $$ = = = 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) .