Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Jun 14 2023 19:49:33 ACUS01 KWNS 141949 SWODY1 SPC AC 141948 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0248 PM CDT Wed Jun 14 2023 Valid 142000Z - 151200Z ....THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM THE ARKLAMISS ACROSS AL INTO SOUTHWEST GA... ....SUMMARY... Significant severe thunderstorms capable of producing all severe hazards, including very large hail, swaths of intense wind gusts/damage, and tornadoes, are expected from the ArkLaTex into the Southeast this afternoon into tonight. ....20Z Update... ....Arklatex into GA... Recent surface analysis places a residual outflow boundary from the MLU (in northeast LA) vicinity eastward to near MGM (in central AL) and then more southeast to north of TLH (in the eastern FL Panhandle). Most of the ongoing storms are just north of this boundary, including the few tornadic supercells over southeast GA. This area was addressed in recently issued MCD 1043, which mentions that a corridor of greater tornado potential may be evolving across portions of southern GA. Longer-lived supercells will likely continue with a risk for large hail and tornadoes (possibly strong) for the next couple of hours. Development farther west across northern LA has shown a trend towards more linear organization/upscale growth, with the outflow boundary potentially providing a favorable corridor for a significant severe-wind threat into central MS. Severe Thunderstorm Watch #293, which contains Particularly Dangerous Situation wording, was recently issued to cover this threat. Several bowing segments and supercells are ongoing between these two areas (i.e. across central MS and central AL), with very large hail and strong gusts possible with these storms as well. Given the robust vertical shear and strong/extreme buoyancy, the severe threat is expected to continue across these areas throughout the evening as well. ....North/Central TX... Warm and very moist conditions are in place across the region, with the recent 18Z FWD sampling almost 5000 J/kg of MLCAPE. An outflow boundary extends from just southwest of PRX southwestward through the Metroplex and SEP to about 50 miles south of ABI. This boundary could be the focus for additional storm development this afternoon. Even so, any development will be battling significant dry air entrainment, which leads to some uncertainty regarding storm coverage. Regardless, any storms that do persist should be accompanied by very large hail (3+" in diameter) and strong downdrafts. ...Mosier.. 06/14/2023 ..PREV DISCUSSION... /ISSUED 1126 AM CDT Wed Jun 14 2023/ ....ArkLaTex to GA through tonight... The unusually strong flow pattern continues from the southern Plains eastward to the Southeast, with 50+ kt midlevel flow across the corridor, coincident with steep midlevel lapse rates and strong buoyancy. Embedded speed maxima will move generally eastward through this corridor, around the southern periphery of the midlevel closed low over the lower Great Lakes. The primary severe threat will continue through the afternoon and into tonight from the ArkLaTex across MS/AL into southern GA. Multiple clusters of severe storms are ongoing, including both supercells and line segments. The cluster in northern MS will likely persist through the afternoon while moving east-southeastward across central AL, where additional supercell development is expected within the warm sector ahead of the cluster. The environment of large buoyancy (MLCAPE 3000-4000 K/kg) and effective bulk shear in excess of 60 kt is quite unusual for mid June into the I-20 corridor, and this will support an unusually high threat for severe storms (including significant severe events). Supercells will be capable of producing isolated very large hail to near 3 inches in diameter with the supercells forming in northeast TX, and with supercells farther east into AL. A complex storm evolution is expected from MS across AL into GA along the buoyancy gradient, as the ongoing clusters and new storms interact and potentially support upscale growth into larger clusters. Swaths of wind damage, some up to 80 mph, can be expected with the MS/AL clusters this afternoon and into GA along the residual outflow boundary. This boundary will locally enhance low-level shear, with the potential for a few tornadoes (a couple of which could be strong), from southwest GA into southeast/central AL with both the isolated supercells and with embedded circulations in any larger clusters. Another cluster could evolve from the northeast TX supercells, and this convection will have a corridor of strong instability to support its maintenance across northern LA into central MS and eventually AL later this afternoon into early tonight. The initial supercells could produce very large hail, while upscale growth will favor swaths of damaging winds (some significant), as well as a few tornadoes. ....Central TX this afternoon/evening... Strong-extreme buoyancy is expected again across central TX, but forcing for ascent will be weak. If sufficient heating/mixing can occur, an isolated storm may form this afternoon along the surface front into central TX. The environment conditionally favors splitting supercells with very large hail, though storm formation/coverage is uncertain. ....Northern Mid-Atlantic/southern New England this afternoon... Pockets of surface heating will drive weak buoyancy to the east of the low across southern New England, where isolated strong-severe storms may occur (see MD #1037 for additional information). $$ = = = 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) .