Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Sep 08 2024 19:44:11 ACUS01 KWNS 081944 SWODY1 SPC AC 081942 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sun Sep 08 2024 Valid 082000Z - 091200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... Organized severe thunderstorms appear unlikely through tonight. ....20Z Update... The forecast remains on track, and no changes/additions were needed to the outlook with this update. In addition to the low-end/ localized convective concerns described below, a couple dry microbursts could accompany high-based thunderstorms developing over the higher terrain in portions of Southern CA this afternoon. While weak deep-layer flow/shear will limit thunderstorm organization/longevity here, a hot/deeply mixed boundary layer (temperatures around 100 F), and lower/middle 50s F dewpoints will still favor a few robust (albeit short-lived) storms capable of locally strong gusts. ...Weinman.. 09/08/2024 ..PREV DISCUSSION... /ISSUED 1116 AM CDT Sun Sep 08 2024/ ....Synopsis and Discussion... Recent surface observations show a nearly stalled front over north FL. Daytime heating of a moist low-level airmass south of this boundary will likely encourage the development of scattered to numerous thunderstorms this afternoon over the northern and central FL Peninsula. While occasional strong/gusty winds may occur with any downdrafts, the presence of poor mid-level lapse rates should hinder updraft acceleration and overall convective intensity. Even with upper ridging remaining prominent over much of the West, high-based convection may develop this afternoon over the southern/central Rockies, and perhaps into the adjacent High Plains along/near a weak lee surface trough. Limited low-level moisture and generally weak effective bulk shear over these regions will likely preclude an organized severe threat, although strong winds may occur with any convection that can be sustained. Water vapor satellite imagery shows a mid-level shortwave trough over the Pacific Northwest this morning. This feature will move generally east-northeastward towards the northern Rockies through the period. Isolated thunderstorms may occur across interior portions of the Northwest this afternoon ahead of the shortwave trough. But, rather modest low-level moisture (surface dewpoints generally in the 30s/40s F) should hinder the development of any more than weak instability. Along with only modestly enhanced mid-level flow, the limited instability is expected to keep any severe wind threat with convective downdrafts across eastern WA/OR into ID and northern NV/UT quite sparse. $$ = = = 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) .