Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Feb 26 2024 17:33:32 ACUS02 KWNS 261733 SWODY2 SPC AC 261731 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST-CENTRAL MISSOURI INTO ILLINOIS...INDIANA...NORTHWEST OHIO...AND SOUTHERN LOWER MICHIGAN... ....SUMMARY... Scattered strong to severe thunderstorms, associated with large hail (some near 2 inch diameter), damaging gusts, and a few tornadoes will be possible from late Tuesday afternoon, into the evening and overnight from parts of the mid Mississippi Valley to the Ohio Valley and southern Lower Michigan. ....Synopsis... Upper pattern is forecast to feature a northern-stream shortwave trough over the northern Rockies early Tuesday morning. At the same time, moderate to strong southwesterly flow within the southern stream will extend from off the Baja coast into the Mid-South. The overall upper pattern will trend toward consolidation as the northern-stream shortwave progresses eastward and evolves into a full latitude trough covering much of the central CONUS by the end of the period early Wednesday morning. Surface low associated with this trough is expected to deepen as it moves across the Upper Midwest and Upper Great Lakes, with notable mass response and low-level moisture advection anticipated through the MS Valley. General expectation is for upper 50s dewpoints to reach the Lower/Middle OH Valley and perhaps even Lower MI by Tuesday evening. A fast-moving cold front attendant to the deepening surface low will progress quickly eastward/southeastward across the Plains and MS/OH Valleys, with thunderstorms anticipated as it interacts with the returning low-level moisture, particularly across the Mid-MS and Lower/Mid OH Valleys. ....Upper OH Valley Early Tuesday... Showers and thunderstorms will likely be ongoing over eastern OH, supported by moderate low-level southwesterly flow and associated warm-air advection regime. Cold mid-level temperatures and attendant steep mid-level lapse rates will support enough buoyancy for deep updrafts, with moderate deep-layer vertical shear contributing to some potential for updraft organization/rotation. As a result, some of these thunderstorms may become strong enough to produce hail. Limited buoyancy should lead to a gradually diminishing storm intensity with eastern extent. ....Mid-MS Valley into Lower/Middle OH Valley and southern Lower MI Tuesday evening and overnight... The airmass across the region is expected to gradually destabilize throughout the day amid a combination of increasing low-level moisture and cooling mid-level temperatures. Even so, the general expectation is for the open warm sector to remain capped throughout the day. Initial thunderstorm development will likely occur via warm advection in the vicinity of the warm front from far northeast IL across northern IN/OH and into Lower MI. The highest storm coverage is anticipated north of the warm front, with steep mid-level lapse rates and strong vertical shear supporting robust updrafts capable of large to very large hail within these elevated storms. There is some chance for storms to interact with the warm front, particularly if development occurs closer to the surface low, where thermodynamic conditions are more supportive of surface-based storms. Backed low-level flow is also possible in these areas, resulting in the potential for supercells capable of all severe hazards, including tornadoes. While the duration and coverage of early evening storms may impact thermodynamics, the general expectation is for another round of thunderstorms to develop along the cold front as it moves through. Initial development of these storms is anticipated from western IL into east-central/southeast MO in the 00-03Z timeframe, with the storms then tracking eastward with the cold front. Most favorable low-level moisture and buoyancy will likely be in place across IL and IN, with the greatest potential for damaging gusts in this region. Buoyancy will lessen with eastern extent into OH, with the expectation that storm intensity will lessen with eastern extent as well. ...Mosier.. 02/26/2024 $$ = = = 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) .