Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat May 06 2023 06:01:26 ACUS02 KWNS 060601 SWODY2 SPC AC 060559 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Sat May 06 2023 Valid 071200Z - 081200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSOURI VALLEY... ....SUMMARY... Severe storms with large hail and wind damage will be possible across parts of the Mid Missouri Valley on Sunday. Marginally severe storms will also be possible in parts of the southern and central Plains, and across parts of the southern Great Lakes and Ohio Valley. ....Mid Missouri Valley... An upper-level ridge is forecast to remain across the western Great Lakes on Sunday as southwest mid-level flow continues across much of the central U.S. At the surface, a cold front is forecast to advance southward into the central Plains and mid Missouri Valley. To the south of the front, surface dewpoints in the 60s F will likely contribute to moderate instability by afternoon. As surface heating takes place and low-level convergence increases along the front, scattered thunderstorm development appears likely from late afternoon into the evening. Although the models still show some variance among solutions, a consensus suggests that a cluster of storms could initiate in south-central Nebraska during the afternoon, moving eastward across southeast Nebraska into southwest Iowa and northwest Missouri by early evening. Forecast soundings ahead of the front in the mid Missouri Valley at 00Z/Monday generally show strong instability (MLCAPE from 3000 to 4000 J/kg), moderate deep-layer shear (0-6 km shear of 40 to 50 knots), and steep mid-level lapse rates near or above 8.0 C/km. This environment would be favorable for supercells with large hail and wind damage. The larger and more dominant supercells could produce hailstones greater than 2 inches in diameter. Although a severe threat appears likely across parts of the mid Missouri Valley on Sunday, there is some uncertainty concerning the timing of the front and distribution of instability. The slight has been placed where confidence is greatest for strong destabilization near or just ahead of the expected position of the front by late afternoon. ....Texas/Oklahoma/Kansas... West-southwesterly mid-level flow is forecast across much of the southwestern and south-central U.S. on Sunday. At the surface, a moist airmass will be located from east and central Texas northward into eastern Kansas. A dryline is expected to be in place on the western edge of this moist airmass by afternoon. To the east of the dryline, strong destabilization appears probable in many areas. A few thunderstorms could develop to the east of the dryline during the mid to late afternoon. The strong instability combined with steep mid-level lapse rates and 0-6 km shear from 30 to 40 knots, should be favorable for an isolated severe threat with supercells possible. However, the severe threat is expected to remain isolated due to the weak forcing, with a localized threat in areas where cells can overcome the cap. ....Ohio Valley/Southern Great Lakes... An upper-level ridge will remain in place across the Great Lakes on Sunday. At the surface, a pocket of maximized low-level moisture is forecast across the Ohio Valley, where surface dewpoints are expected to be in the 60s F. As moderate instability develops during the day, isolated to scattered thunderstorms will be possible within this moist airmass. Forecast soundings in the Ohio Valley during the afternoon suggest that 0-6 km shear should generally remain less than 35 knots. This combined with the negative influence of the upper-level ridge should keep any severe threat isolated and marginal. ...Broyles.. 05/06/2023 $$ = = = 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) .