Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Aug 09 2024 19:55:33 ACUS01 KWNS 091955 SWODY1 SPC AC 091953 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ....SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ....20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ...Mosier.. 08/09/2024 ..PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ....Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ....Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ....Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. $$ = = = 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) .