Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Jul 12 2023 05:54:46 ACUS02 KWNS 120554 SWODY2 SPC AC 120553 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Wed Jul 12 2023 Valid 131200Z - 141200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY... ....SUMMARY... Thunderstorms associated with hail and strong gusty winds will be possible on Thursday from parts of the southern and central Plains into the mid Mississippi Valley and Northeast. A few storms with hail and strong wind gusts could also occur in parts of the mid Missouri Valley. ....Mid Mississippi Valley/Ohio Valley/Northeast... An upper-level trough is forecast to move eastward through the Great Lakes on Thursday. At the surface, a cold front is forecast to move into the mid Mississippi and Ohio Valleys. Surface dewpoints ahead of the front will be mostly in the 60s F, which could yield moderate instability in areas that heat up the most. Thunderstorm development is expected to take place along and near the front during the afternoon. The greatest potential for convective development is forecast across Ohio, where several models suggest that MCS development will be possible. NAM forecast soundings in central and eastern Ohio at 00Z/Friday have MLCAPE near 2500 J/kg and 0-6 km shear in the 40 to 50 knot range. This environment would support supercells. If supercells can develop during the late afternoon, large hail and wind damage would be possible. Otherwise, a marginal severe threat is expected to develop across much of the lower Ohio Valley and in the lower Great Lakes region. Damaging wind gusts and hail are expected to be the primary threats. ....Southern and Central Plains/Ozarks... West-northwesterly mid-level flow will be in place on Thursday across much of the central U.S. At the surface, a cold front is forecast to move southward through the central Plains. Pockets of moderate instability will likely develop to the south of the front, potentially from the Texas Panhandle eastward into the Ozarks. A narrow north-to-south corridor of moderate instability may also develop in parts of the central High Plains. Scattered thunderstorms appear likely to form within this airmass as surface temperatures warm in the afternoon. Moderate deep-layer shear is forecast across much of this airmass, which will likely support a severe threat in areas where instability and shear become locally maximized. Convective mode is expected to be mostly multicellular and an isolated threat for wind damage and hail will be possible. However, the greatest severe threat will be dependent upon mesoscale factors which have low predictability at this time. ....Mid Missouri Valley... West-northwest mid-level flow will be in place across the north-central states on Thursday. A surface high is forecast to move southeastward into the lower Missouri Valley. In the wake of this surface high, a pocket of maximized low-level moisture is forecast across western Iowa where surface dewpoints could reach the mid 60s F. As surface temperatures warm during the day, a small pocket of moderate instability will be possible across the mid Missouri Valley. Thunderstorms that develop within this pocket of instability will likely have access to moderate deep-layer shear, owing to directional shear in the low-levels and speed shear in the mid-levels. This environment could support a marginal severe threat, with strong wind gusts and hail as the primary threats. ...Broyles.. 07/12/2023 $$ = = = To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .