Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Aug 22 2024 17:29:50 ACUS02 KWNS 221729 SWODY2 SPC AC 221728 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Thu Aug 22 2024 Valid 231200Z - 241200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM UTAH AND WESTERN COLORADO NORTHWARD INTO EASTERN IDAHO AND SOUTHWEST MONTANA...AND OVER PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ....SUMMARY... Isolated to perhaps scattered severe storms with strong to severe gusts will be possible on Friday across parts of the parts of the Intermountain West and central Rockies, and over a narrow portion of the central and northern High Plains. ....Synopsis... On Friday, an upper high will remain centered over the southern Plains, while a large trough develops across the West. The primary midlevel wave will eject northeastward across the Great Basin and into ID and MT through 00Z, providing substantial cooling aloft. Lift with this feature will be focused from northern NV and UT into MT. Overnight, a secondary lobe of vorticity will swing east across much of northern CA and OR. At the surface, low pressure will deepen throughout the day ahead of a cold front which will extend from the Bitterroots southwestward into central NV by 21Z. Farther east, another trough will extend from the low in western MT southeastward into the northern and central High Plains. Midlevel moisture already in place across the Four Corners states will spread north across UT and into MT, which will combine with daytime heating and cooling aloft to result in marginal instability. Farther east, backed/southeasterly surface winds will maintain a plume of lower 60s F dewpoints as far west as far eastern MT to northeast CO. ....Great Basin into eastern ID/western WY... A large area of moderate southwest flow aloft will spread east across the region as the negative-tilt wave passes through NV/UT relatively early in the day. While this wave is timed more favorable farther north, instability may be less favorable than points south. Given the moisture in place, storms will form over a large area beginning mid/late morning over UT and expending into eastern ID/western WY by midday. This is not timed particularly well in terms of diurnal heating, but strengthening wind fields may aid gust potential. Additional diurnally driven cells are then expected along and east of the Wasatch, with marginal hail or wind threat as this activity spreads northeast. The western fringe of the Marginal Risk may be a bit generous over ID given uncertainties with how quickly drying will occur from the west. ....Northern and central High Plains... Daytime heating will lead to an unstable and uncapped air mass over the High Plains, with storms expected to form roughly near a Billings to Cheyenne line by late afternoon. Further development is possible into eastern/northeastern CO as well. Given that these areas are well east of the cyclonic flow regime aloft, any severe is expected to be relatively isolated or in sparse clusters. However, both localized damaging gusts or hail will be possible, though wind profiles will generally favor disorganized storms. ...Jewell.. 08/22/2024 $$ = = = 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) .