Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Jul 15 2023 20:02:26 ACUS01 KWNS 152002 SWODY1 SPC AC 152000 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sat Jul 15 2023 Valid 152000Z - 161200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHERN HIGH PLAINS... ....SUMMARY... Severe thunderstorms are expected across the High Plains of eastern New Mexico into the Texas South Plains today, where isolated very large hail and significant damaging wind gusts will be possible. Isolated strong to severe storms may also be noted from the Tennessee and Ohio Valley region to the mid-Atlantic and northeast states. ....ArklaTex into northern TX... A plume of deep moisture with PWAT over 2.00" remains across the area, and visible imagery shows signs of convection developing from southeast OK into southwest AR. Given strong instability, locally strong downbursts or marginal hail will be possible, and the Marginal Risk has been expanded into southwest AR. Farther west into northern TX, strong heating south of the area of cloudiness is leading to increasing CU fields, and isolated downbursts will be possible with any storms that form in this area as well. For more information see forthcoming mesoscale discussion 1566. ...Jewell.. 07/15/2023 ..PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 15 2023/ ....Eastern NM/West TX... An outflow boundary resulting from overnight storms extended from northeast NM into the southern TX Panhandle this morning, and was continuing to move west towards the higher terrain of northeast NM. Clearing/heating of a moist air mass to the north of this boundary, in combination with mid-level lapse rates of around 8 deg C/km, will result in MLCAPE of 1500 to 2000 J/kg by afternoon. Large scale forcing is subtle, but thunderstorm development is expected over the mountains of northeast NM, with storms spreading southeastward toward the TX Panhandle this evening. Northwesterly mid-level flow will result in ample shear for supercells capable of large to very large hail initially, with damaging winds becoming increasingly likely as storms congeal into a southeast-moving MCS with time. A small significant hail area has been introduced where initial supercell development is most probable, and a significant wind area has been introduced based on the 12z HREF CAM guidance and where higher confidence exists in 65 kt/75 mph gusts occurring. ....Ohio Valley/Appalachians to Northeast... Broadly cyclonic upper-level flow will persist over much of the eastern U.S. today. Thunderstorms are expected to develop, or diurnally intensify, along and ahead of a cold front as it moves steadily east this afternoon. In addition, somewhat greater coverage is expected in association with a mid-level impulse moving east through KY/TN. A rather broad area will exist of at least moderate MLCAPE and sufficient mid-level flow for some degree of storm organization, and the Marginal Risk has been expanded east across portions the mid-Atlantic and northeast states. Where pockets of greater heating can occur, locally higher MLCAPE and steep low-level lapse rates will support a risk for damaging wind gusts. ....Central Nebraska... Thunderstorms may develop in the 10z-12z time frame Sunday morning within a low-level warm/moist advection regime over central NE. Although some potential for strong storms will exist, have opted not to introduce a Marginal Risk area with this outlook due to concerns regarding the degree of elevated instability. $$ = = = 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) .