Subj : DAY2SVR: Nws Storm Predic To : All From : Mike Powell Date : Tue Jun 06 2023 15:53:00 ACUS02 KWNS 061709 SWODY2 SPC AC 061707 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1207 PM CDT Tue Jun 06 2023 Valid 071200Z - 081200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS...NORTHWEST...NORTHERN PLAINS/UPPER MIDWEST...COASTAL CAROLINAS...AND FLORIDA... ....SUMMARY... Isolated strong to severe thunderstorms appear possible Wednesday across parts of the southern High Plains, Northwest, northern Plains/Upper Midwest, Carolinas vicinity, and Florida. ....Synopsis and Discussion... The overall upper-air pattern is forecast to remain relatively unchanged from Tuesday through Wednesday across the CONUS. Upper ridging will persist across the northern and central Plains, with some expansion northward/northwestward into more of southern British Columbia and the southern Prairie Provinces. Cyclonic flow will also persist across the northeastern CONUS, anchored by a closed low centered over ME. Several shortwave troughs are expected to move through this cyclonic flow, include one that moves into the Mid-Atlantic during the late evening. Farther west, an upper low over southern CA is expected to gradually drift northward into southern NV. Some enhancement of the subtropical jet is forecast south of this low, stretching across the Baja Peninsula and northern Mexico into Texas. .....Southern High Plains to the Southeast and FL Peninsula... A nondescript surface pattern will be in place, with only modest lee troughing across the High Plains and the deepest area of low pressure over ME. Even so, a relatively moist low-level air mass will contribute to thunderstorm development across portions of the Southeast and southern Plains/southern High Plains. Within this broader region, a few areas appears to higher a relatively greater severe risk including the southern High Plains, coastal Carolinas, and the east coast of FL. In each of these areas, a modest increase in deep-layer flow may result in stronger shear and the potential for a more robust updrafts. A predominantly multicellular mode is anticipated in each of these area as well, but loosely organized thunderstorm clusters spreading eastward may be capable of producing isolated severe gusts as low-level lapse rates steepen through the day. A few supercells are possible across the TX Trans Pecos where buoyancy will be greatest. ....Lower MO Valley into the Eastern Dakotas... A ribbon of greater low-level moisture is anticipated from the Lower MO Valley north-northwestward into eastern Dakotas. Here, increasing low-level convergence is expected along a stationary boundary separating the drier airmass over the Great Lakes from the one over the Plains. Afternoon thunderstorm development is forecast within this environment after the airmass destabilizes. Shear will be modest, but a few stronger storms capable of damaging gusts and isolated hail are possible. .....Northern CA into the Northern Great Basin... A shortwave trough rotating through the CA upper low will contribute to increasing thunderstorm coverage and low severe-thunderstorm potential across the region Wednesday afternoon and evening. Low-level moisture will be modest, but increasing mid-level moisture and cold mid-level temperatures will boost buoyancy, helping support stronger updrafts. Additionally, high cloud bases atop a deeply mixed boundary layer will aid in the development of strong downdrafts, with damaging gusts as the primary threat across the region. Given the cold mid-level temperatures, a few isolated instances of hail are also possible. ...Mosier.. 06/06/2023 $$ --- SBBSecho 3.14-Linux * Origin: Ilink: CCO - capitolcityonline.net (454:1/105) .