SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Sat Sep 23 2023 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE SOUTHERN PLAINS... ...SUMMARY... Thunderstorms, associated with large hail and wind damage, will be possible on Sunday from parts of north-central Texas northeastward into southeast Oklahoma and western Arkansas. ...Synopsis... A mid-level trough will deamplify over the Upper MS Valley as upper riding builds in from the west across the Plains states tomorrow/Sunday. Despite weakening upper support, a surface cold front will sweep across portions of the southern Plains, providing enough low-level convergence and lift to support scattered strong to severe storms amid appreciable buoyancy and vertical wind shear. Meanwhile, the remnants of Ophelia will continue to meander across the Mid Atlantic, with periodic heavy rains and an occasional thunderstorm attempting to move onshore. ...Southern Plains... Scattered strong to severe thunderstorms, potentially in the form of one or more MCSs, may already be in progress ahead of the surface cold front across the southern Plains. Though these storms may inhibit morning destabilization near the Arklatex, guidance consensus suggests that at least some clearing and destabilization is likely ahead of the cold front, especially from southern OK into north-central TX. Here, 8+ C/km mid-level lapse rates atop surface dewpoints around 70 F will boost MLCAPE to over 3000 J/kg in spots. Veering winds in the lowest few hundred mb will result in hodographs with at least modest curvature and elongation, supporting supercell structures with storms that develop ahead of the cold front by afternoon. Large to very large hail will be the main threat with the more robust supercells, though a severe gust or tornado cannot be ruled out. Supercells and their cold pools should merge after a few hours, supporting one or more multicellular complexes or MCSs with severe-gust potential. Primary uncertainties precluding higher severe probabilities (especially hail) at this time involve the specific placement and timing of the cold front, as well as impacts made by preceding storms from Day 1 and rapidity of supercell upscale growth. ...Mid Atlantic... Though strong low-level directional shear should be present within the northeast quadrant of Ophelia's remnants, latest guidance consensus suggests that any buoyancy that can manage to reach the shoreline should be scant at best. Though the threat for a brief tornado is non-zero, such meager to near non-existent buoyancy precludes the addition of tornado probabilities this outlook. ..Squitieri.. 09/23/2023
