Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Jun 05 2023 07:31:33 ACUS03 KWNS 050731 SWODY3 SPC AC 050730 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Mon Jun 05 2023 Valid 071200Z - 081200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE INTERIOR PACIFIC NORTHWEST...SOUTHERN HIGH PLAINS...AND SOUTH CAROLINA VICINITY... ....SUMMARY... Isolated strong to severe thunderstorms appear possible Wednesday across parts of the interior Pacific Northwest, southern High Plains, and South Carolina vicinity. ....Synopsis... A quasi-omega blocking pattern will continue over the CONUS on Wednesday, with a weak upper low over CA and the western Great Basin, upper ridging over much of the Plains, and another upper trough/low persisting over parts of the eastern states. ....Northern California into Oregon/Idaho/Western Montana... Similar to Day 2/Tuesday, thunderstorms should initially develop over the higher terrain of northern CA due to orographic influences and weak ascent on the northern periphery of an upper low. With seasonably cool temperatures aloft and modest deep-layer shear forecast, some of these thunderstorms could produce marginally severe hail. Additional convective development should occur farther east into OR/ID and parts of western MT. While low-level moisture is forecast to remain rather limited, sufficient instability to support high-based thunderstorms is still forecast. 20-30 kt of effective bulk shear should also provide modest updraft organization. Isolated severe wind gusts should be the main threat with convective clusters as they spread generally west-northwestward with time. Some hail could also occur with initial development. ....Southern High Plains... Thunderstorms should once again develop across the higher terrain of central/eastern NM and west TX Wednesday afternoon. Although weak upper ridging will persist, modestly enhanced mid/upper-level westerly winds are forecast with southward extent across this region in association with a sub-tropical jet. Deep-layer shear should generally range around 20-30 kt, perhaps slightly weaker towards CO/KS. Loosely organized thunderstorm clusters spreading eastward Wednesday afternoon/evening may be capable of producing isolated severe gusts as low-level lapse rates steepen through the day. Occasional large hail also appears possible, especially across parts of west TX where effective bulk shear may be slightly stronger. ....South Carolina Vicinity... A weak surface trough/front should be draped across parts of the Southeast. A seasonably moist low-level airmass will likely be in place along/south of this boundary. Moderate instability should develop in a narrow corridor across parts of GA into SC and far southern/coastal NC by Wednesday afternoon. Stronger mid-level westerly flow associated with an upper trough/low should gradually overspread the warm sector through the day. Sufficient deep-layer shear to support organized convection should be present, but weak low-level convergence along the boundary casts some uncertainty regarding thunderstorm coverage. Still, have opted to include low severe probabilities where most guidance suggests robust convection will develop. ...Gleason.. 06/05/2023 $$ = = = 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) .