Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Jan 10 2023 05:56:36 ACUS01 KWNS 100556 SWODY1 SPC AC 100555 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1155 PM CST Mon Jan 09 2023 Valid 101200Z - 111200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF CENTRAL/SOUTHERN CA...PARTS OF SOUTHEAST NV...NORTHWEST AZ...SOUTHWEST UT... ....SUMMARY... Isolated strong to severe thunderstorms capable of producing damaging winds and perhaps a brief tornado may occur today across parts of southern/central California. Thunderstorms capable of isolated severe gusts will also be possible across parts of southeast Nevada, northwest Arizona, and southwest Utah. ....California Coast into the Sacramento/San Joaquin Valleys... A strongly forced convective line is expected to move onshore across parts of the central/northern CA coast just before the start of the forecast period (12Z this morning), in conjunction with an intense deep-layer cyclone over the eastern Pacific. Despite meager instability, strong low-level and deep-layer flow/shear will support a threat of locally damaging gusts and perhaps a brief tornado as this line moves onshore and eventually spreads into portions of the Sacramento and San Joaquin Valleys. Some weakening of this convective line is expected with time as the primary cyclone begins to occlude, but cooling temperatures aloft and steepening midlevel lapse rates may support a few stronger cells or line segments within a post-frontal regime through the day, with enough residual flow/shear to support a continued threat of locally strong/damaging gusts. The stronger post-frontal convection may also produce small hail, but buoyancy appears too limited to support a severe-hail risk at this time. ....Parts of the Southern Great Basin... As the occluding cyclone lifts northward near the OR/northern CA coast, the southern portion of the primary mid/upper-level shortwave trough will continue to progress eastward across southern CA and eventually into the southern Great Basin by late afternoon. A weak surface low may develop in the lee of the Sierras in association with this shortwave trough and attendant cold front. Modest diurnal heating will support some weak destabilization along/ahead of the front across portions of the Great Basin, with redevelopment of a convective frontal band possible during the afternoon. While storm intensity will generally be limited by weak buoyancy, rather strong low/midlevel flow and modest steepening of low-level lapse rates will support some threat of locally severe gusts as convection spreads from southeast NV into northwest AZ and southwest UT. ...Dean/Supinie/Squitieri.. 01/10/2023 $$ = = = 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) .