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ACUS02 KWNS 091737 SWODY2 SPC AC 091735 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1135 AM CST Sat Dec 09 2023 Valid 101200Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE SOUTHEAST AND TOWARD PARTS OF THE MID ATLANTIC... ...SUMMARY... Isolated severe thunderstorms will be possible through Sunday evening across parts of the Southeast States, mainly in the form of sporadic damaging winds and a few brief tornadoes. ...Synopsis... A highly amplified upper trough will move from the MS Valley toward the East Coast on Sunday, with a primary embedded speed max ejecting quickly from the northern Gulf Coast toward the Mid Atlantic. At the surface, a cold front will push east across the Appalachians during the afternoon, with the strongest frontal surge across the Southeast late in the day and into the evening. Ahead of the cold front, a surface trough will gradually deepen from MD southwestward to the FL Panhandle, with 40-50 kt southerly 850 mb flow aiding moistening. Front-parallel winds aloft as well as modest destabilization will likely lead to scattered storms, with a few becoming severe across the region. ...Parts of the Southeast and East Coast... Scattered storms are likely to be ongoing along the front from southern AL and the western FL Panhandle across northern GA and the Appalachians Sunday morning, with substantial low clouds across much of the region. Lack of appreciable heating will generally reduce available instability, but sufficient boundary layer moisture with low to perhaps mid 60s F dewpoints will result in a few hundred J/kg MLCAPE ahead of the cold front. The strongest cooling aloft will occur behind the boundary, as the upper trough will be quite amplified with meridional flow aloft. Storms across the Southeast may eventually become linear as the cold front accelerates, and this may yield a few damaging gusts. Low-level shear may also favor isolated supercells with brief tornado threat, with the main mitigating factor being lack of heating. Any pockets of strong heating that do develop could yield mesocale areas of higher potential, and the southeastern area will be monitored going into the Day 1 period. Farther north into the Mid Atlantic, boundary layer stability will likely reduce severe potential to Marginal Risk levels due to the combination of weak lift/convergence combined with the cloudy/saturated profiles. Still, strengthening mean winds in the lowest few km may support strong to perhaps damaging gusts. ..Jewell.. 12/09/2023 $$