Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Jun 15 2023 05:00:09 ACUS02 KWNS 150500 SWODY2 SPC AC 150458 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1158 PM CDT Wed Jun 14 2023 Valid 161200Z - 171200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FRIDAY INTO FRIDAY NIGHT ACROSS MUCH OF CENTRAL AND SOUTHERN ARKANSAS...NORTHEASTERN LOUISIANA...MUCH OF MISSISSIPPI...SOUTHERN ALABAMA...SOUTHWESTERN GEORGIA...THE WESTERN FLORIDA PANHANDLE...PARTS OF SOUTHEASTERN COLORADO...SOUTHWESTERN KANSAS...AND THE OKLAHOMA/TEXAS PANHANDLES... ....SUMMARY... Scattered strong to severe thunderstorms, including organizing clusters, are possible Friday through Friday night in a corridor across the central Great Plains through the lower Mississippi Valley and parts of the Southeast. ....Synopsis... Within the prevailing split mid/upper flow, it appears that another mid-level low will evolve across parts of the northern Mid Atlantic and southern New England during this period, accompanied by modest surface cyclogenesis east of the Blue Ridge into areas off the northern Mid Atlantic coast by late Friday night. This low is forecast to form within persistent larger-scale troughing, which likely will remain in phase with troughing in a separate branch of westerlies across the Southeast while slowly beginning to shift across the Atlantic Seaboard. Farther west, a prominent subtropical high will remain centered near the lower Rio Grande Valley. However, models have been varying concerning the northward extension of the stronger mid-level ridging to its north, across the southern Great Plains, as a series of short wave perturbations continue to emerge from lingering weak larger-scale troughing across the interior West through subtropical eastern Pacific, and progress around its northern periphery. Currently it appears probable that one notable, convectively augmented subtropical perturbation will be in the process of migrating north of the southern Great Plains Red River early in the period, before continuing eastward and southeastward through the lower Mississippi Valley. Another notable subtropical perturbation is forecast to follow, across the southern Rockies into the central Great Plains, ahead of slow moving mid-latitude perturbation across the Great Basin. With seasonably high moisture content and instability remaining confined beneath the southern Great Plains ridging, and along/south of a lingering surface front/convective outflow into the eastern Gulf Coast vicinity, stronger thunderstorm potential will remain focused around the northern periphery of the ridging into the base of the Southeastern mid-level troughing. ....Lower Mississippi Valley into eastern Gulf Coast... Convective potential through this period will largely depend on sub-synoptic and mesoscale features with relatively low predictability even in the Day 2 period. One or two clusters of storms may be ongoing at the outset of the period, possibly including one associated with the lead subtropical perturbation. This convectively enhanced feature, and associated seasonably strong mid-level wind fields, seems likely to provide support for intensifying convection as the boundary-layer destabilizes across Arkansas into Mississippi and Alabama during the day. The environment may become characterized by large mixed-layer CAPE, beneath relatively steep mid-level lapse rates, and supportive of initially discrete supercell structures before evolving into growing clusters. This activity may be accompanied by the risk for large, damaging hail and severe wind while progressing east-southeastward through Friday evening. ....Central Great Plains... In the wake of the lead subtropical perturbation, models indicate more uncertain destabilization ahead of the following impulse. However, by late afternoon, strengthening shear and forcing for ascent probably will support a risk for a few supercells near/north and east of the Raton Mesa vicinity. It is possible that this activity could evolve into an organizing cluster while spreading eastward into the adjacent Great Plains, and pose a continuing risk for severe wind before weakening Friday evening. ....Mid Atlantic... Thermodynamic profiles characterized by steepening low-level lapse rates associated with daytime heating, beneath relatively cool temperatures associated with the developing mid-level low, may become sufficient for vigorous thunderstorm development Friday. This activity may initiate near the Blue Ridge, before intensifying Friday afternoon while propagating into deepening surface troughing. Aided by seasonably strong deep-layer shear, organized convection, perhaps including isolated supercell structures, may pose at least some risk for severe hail and wind. ...Kerr.. 06/15/2023 $$ = = = 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) .