Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Jul 28 2024 07:31:54 ACUS03 KWNS 280731 SWODY3 SPC AC 280730 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Sun Jul 28 2024 Valid 301200Z - 311200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN PLAINS TO THE MIDWEST...OHIO VALLEY...AND TENNESSEE VALLEY... ....SUMMARY... Scattered strong to severe storms will be possible across a broad region from the northern Plains to the Midwest, Ohio Valley, and Tennessee Valley. ....Synopsis... Tuesday morning, a low-amplitude mid-level ridge will be centered across the central CONUS with a trough across the western and eastern CONUS. This pattern will shift east through the day Tuesday and into Tuesday night. Beneath the ridge, a very moist airmass will be present with mid 70s to near 80 dewpoints extending from the Gulf of Mexico to the Upper Midwest. This will result in a large region of strong instability along and south of a stationary front which will extend from the Dakotas to the Midwest. This front may serve as a focus for multiple rounds of severe storms on Tuesday. ....Northern Plains... As the upper-level ridge shifts east on Tuesday, the surface lee trough will strengthen across the Plains. Some height falls/embedded shortwave troughs are expected to overspread the Dakotas on Tuesday afternoon. This may be sufficient forcing for scattered thunderstorm development Tuesday afternoon/evening. Mid-level westerly flow around 25 to 30 knots combined with southerly/southeasterly flow will provide ample shear for storm organization including the potential for supercells. Eventual upscale growth into an MCS is possible as the low-level jet strengthens across the northern Plains after sunset. Instability may be somewhat lacking during the day given the well mixed airmass and better low-level moisture farther east. However, low level moisture is expected to increase through the day and storms may move into this more moist and unstable airmass during the evening. ....Midwest into the Ohio and Tennessee Valleys... On Tuesday, a favorable MCS pattern will set up across the Corn Belt and into the Tennessee Valley. A very moist airmass will be in place (surface dewpoints near 80F) along a frontal zone, with moderate (35-40 knot) mid-level flow parallel to this front. Details remain uncertain at this time and storm coverage remains conditional given height rises across the region. Mesoscale details may warrant higher probabilities in later outlooks, but uncertainty is too high at this time for more than a Marginal (1/5) Risk. ...Bentley.. 07/28/2024 $$ = = = 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) .