SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Tue Aug 15 2023 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS LOWER MICHIGAN AND NORTHWEST OHIO... ...SUMMARY... Isolated strong to severe thunderstorms are possible across Lower Michigan and northwest Ohio on Thursday. ...Synopsis and Discussion... A shortwave trough will likely extend from central Ontario southwestward through WI early Thursday morning. This shortwave, and accompanying strong mid-level flow, are forecast to progress eastward across the Upper Great Lakes and Ohio Valley throughout the day, continuing into the Lower Great Lakes and northern Mid-Atlantic by early Friday morning. An associated cold front will push eastward just ahead of this shortwave, ending the period arcing from eastern NY across eastern PA and back into the TN Valley. Thunderstorms will likely be ongoing on this front as it moves through the Upper Great Lakes region early Thursday morning. Buoyancy will be limited ahead of the front across the Lower MI and the OH Valley, but some modest destabilization is possible. This destabilization, coupled with the strong wind fields accompanying the shortwave, could lead to some intensification of the storms along the front as they move eastward. Greatest severe potential is expected over Lower MI and northwest OH where a few stronger gusts are possible. Farther west, increased mid-level moisture will be in place from northern CA into the western Great Basin downstream of an upper low off the CA coast. Modest mid/upper level flow will extend across the region and a few strong to severe storms could develop within this regime. However, any strong to severe storm would be relatively short lived, and the overall severe potential is too low to delineate an outlook area. Elsewhere, expansive upper ridging initially centered in the Four Corners vicinity is expected to drift eastward, ending the period centered over the TX Panhandle and OK. Afternoon thunderstorms are likely beneath this ridge, predominantly over the higher terrain of the eastern Great Basin and central/southern Rockies. Lastly, afternoon thunderstorm are also possible within the moist airmass from coastal Carolinas into FL. In these two areas, weak vertical shear will keep the severe-thunderstorm potential low. ..Mosier.. 08/15/2023
