Subj : DAY2SVR: Marginal Risk To : All From : Mike Powell Date : Thu Aug 24 2023 07:46:00 ACUS02 KWNS 240443 SWODY2 SPC AC 240441 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1141 PM CDT Wed Aug 23 2023 Valid 251200Z - 261200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FRIDAY INTO FRIDAY NIGHT ACROSS PARTS OF THE MID ATLANTIC...LOWER OHIO VALLEY...LOWER MISSOURI VALLEY...AND CENTRAL GREAT PLAINS... ....SUMMARY... Scattered strong thunderstorms may impact a corridor from the Mid Atlantic and lower Ohio Valley through the lower Missouri Valley and central Great Plains Friday afternoon into Friday night, accompanied by at least some risk for damaging wind gusts. ....Synopsis... Models indicate that large-scale troughing at mid/upper levels will begin to evolve across the Upper Midwest into the northern Atlantic Seaboard during this period. However, the most substantive amplification may not occur until Friday night east of the lower Great Lakes region, in response to a short wave trough digging southeast of the upper Great Lakes vicinity. This perturbation likely will be preceded by a more modest impulse, which may be in the process of turning eastward offshore of the Mid Atlantic coast by early Friday. Otherwise, mid-level ridging is forecast to remain prominent either side of an axis extending from a high over the Texas Panhandle vicinity into the Southeast. Broad amplified ridging is also likely to persist north-northwest of the high, through the northern Rockies, downstream of a broad evolving low, increasing cut off from the westerlies, offshore of the Pacific coast. Around the periphery of the high, the weakened remnants of Harold may slowly translate across and east of the Colorado Rockies, while another easterly wave passes to the south of the lower Texas coast. In lower-levels, it still appears that notable low-level cooling and drying will continue to advance south of the Canadian/U.S. border to the east of the Rockies. While an initial cold front may reach the Mid Atlantic region by early Friday, it now appears that it may not advance into the lower Ohio River vicinity until Friday afternoon and the lower Missouri River vicinity until late Friday evening. Another surge of cooler may nose south of the Wyoming/Colorado Rockies during the day Friday, with more notable cooling and drying overspreading the northern Great Plains and Great Lakes region late Friday through Friday night. ....Mid Atlantic/lower Ohio Valley into the central Great Plains... Moderate to large mixed-layer CAPE likely will develop once again along and south of the conglomerate leading edge of the low-level cooling. It appears that this will largely be supported by strong daytime heating beneath steep lower/mid-tropospheric lapse rates, as profiles farther aloft remain warm with weak lapse rates. It is now also appearing increasingly likely that this destabilization will be confined to areas south of the favorably sheared mid-level westerlies, with mid/upper support for convective development also weak or uncertain, aside from the possible influence of the remnants of Harold across parts of the central Great Plains. However, models suggest that at least widely scattered thunderstorm development is possible by late Friday afternoon into evening, in an environment conducive to locally strong downbursts and perhaps modestly organizing clusters with cold pools posing a risk for potentially damaging wind gusts. ...Kerr.. 08/24/2023 $$ --- SBBSecho 3.14-Linux * Origin: Ilink: CCO - capitolcityonline.net (454:1/105) .