Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Aug 03 2023 19:52:42 ACUS01 KWNS 031952 SWODY1 SPC AC 031951 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Aug 03 2023 Valid 032000Z - 041200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE CENTRAL PLAINS... ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE TN VALLEY AND NORTHWEST NY... ....SUMMARY... The most concentrated threat for severe gusts and large hail will be later this afternoon into early tonight across parts of the central Plains. ....Discussion... The only appreciable change made to the previous convective outlook was to adjust severe probabilities across parts of TN/AL/GA based on the evolution of the broken band of storms this afternoon over AL/GA. ...Smith.. 08/03/2023 ..PREV DISCUSSION... /ISSUED 1127 AM CDT Thu Aug 03 2023/ ....Central High Plains later this afternoon into tonight... A midlevel shortwave trough over northwest CO/southwest WY will begin to turn more eastward this afternoon/evening, with a belt of modestly enhanced midlevel flow expected to overspread the central High Plains this afternoon into early tonight. Residual boundary-layer dewpoints at or above 60 F in the post-frontal environment, along with daytime heating in cloud breaks, will drive moderate buoyancy this afternoon/evening from northeast CO eastward into northern KS. Diurnal convection is expected to first form by mid afternoon near or just east of the Front Range, and storms will subsequently spread eastward across east/northeast CO and southwest NE while gradually growing upscale through storm interactions. Isolated large hail will be possible the more discrete/initial storms that could have some supercell structures given modest hodograph length and effective bulk shear near 35 kt and midlevel lapse rates greater than 7 C/km. Damaging winds will become the primary threat this evening into early tonight, with a few swaths of 60-75+ mph winds possible. ....TN Valley this afternoon/evening... The remnants of an overnight MCS in MO has now progressed into southern middle TN and extreme northern AL, with a general weakening trend over the past few hours. Diurnal destabilization is ongoing to the south-southwest of the weakening storms from northeast MS across northern/central AL into northwest GA, but there is uncertainty regarding the future evolution of the ongoing storms. One possibility is for some intensification along the leading outflow as the convection moves toward northwest GA/northeast AL through early-mid afternoon, though the storms/outflow are not phased particularly well with the more unstable warm sector. Also, the stronger midlevel flow tends to lag the initial convection, and these concerns keep confidence low in the evolution of the afternoon storms (and any resultant wind damage threat). Aside from diurnal intensification, there will be the potential for late evening/early overnight storm formation in another west-northwest/east-southeast oriented band from TN into northern AL. Given the inherent uncertainty in the forecast and at least two possible storm scenarios, will only make minor changes to the ongoing outlook. ....NY to eastern Lower MI this afternoon into tonight... An embedded speed max is rotating east-southeastward over southern ON and will reach the Saint Lawrence Valley by late evening/early tonight. Some convection is ongoing in association with this shortwave trough and a surface cold front, and some low-level warming/moistening will occur ahead of the front from ON into northwest NY through this evening. The primary convective threat will likely to spread into northwest NY near or after sunset, but there will still be some potential for isolated damaging winds, especially if an storms evolve into an organized band prior to crossing into NY late this evening into tonight. Farther west into Lower MI, thunderstorm coverage is more in question, given that the stronger forcing for ascent will pass to the north of this area. Lapse rates/buoyancy and some modest enhancement to deep-layer vertical shear will conditionally favor the potential for isolated wind damage or some hail, but storm coverage is likely to remain rather isolated. $$ = = = 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) .