Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Jul 25 2023 07:31:19 ACUS03 KWNS 250731 SWODY3 SPC AC 250730 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Tue Jul 25 2023 Valid 271200Z - 281200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR THE NORTHEAST INTO PARTS OF THE MID-ATLANTIC STATES... ....SUMMARY... Widely scattered severe thunderstorms are forecast across southern New England southward into portions of the Mid-Atlantic states on Thursday. ....Synopsis... A mid-level high will remain across the southern states while a progressive upper-air pattern is forecast over the northern tier of states. A mid-level shortwave trough initially over the Lower Great Lakes is forecast to move offshore New England by late Thursday evening. A mid-level speed max over the MN Boundary Waters will move quickly east into southern Quebec during the period. A cool front/surface trough is forecast to sweep east through much of the Northeast. A surface low over western Ontario will develop east while a trailing cold front settles southward into the Upper Midwest and becomes oriented west to east. ....Northeast into the Mid-Atlantic states... Scattered showers/thunderstorms will probably be ongoing Thursday morning across western/northern NY in association with a LLJ. A seasonably moist boundary layer is forecast to over the entire region and cloud breaks/heating will likely lead to moderate destabilization across much of southern New England. As a weak capping inversion erodes by midday, scattered to numerous storms will likely form by early-mid afternoon. Appreciably strong low to mid-level flow fields indicated by some model guidance lends concerns for both severe gusts with an organizing band of storms, and some potential for storm-scale rotation via cellular or linear modes. Farther south into the Mid-Atlantic states, weaker large-scale ascent will partially be offset by very warm/humid conditions in lee of the higher terrain for storms to initiate. Damaging gusts and perhaps large hail with the heavier cores are expected through the early evening. ....Upper Midwest into the central Great Plains... A more subtle, weakly forced regime is expected across the Upper Midwest into the central Great Plains on Thursday. As a front sags southward into parts of WI, MN, and SD during the day, the airmass along and south of the boundary is forecast to become moderately to strongly unstable. The southern fringe of stronger westerly high-level flow and steep lapse rates will favor vigorous storms. The main variable limiting confidence in this forecast is storm coverage across the region. It seems at least isolated thunderstorms will develop near the boundary and the stronger storms will be capable of a hail/wind hazard. Farther southwest into the central High Plains, lower storm coverage is expected near a surface trough. Some strengthening of an 850-mb LLJ is depicted during the evening into the overnight across KS into the IA/northern MO vicinity. This may aid in additional storms developing late or perhaps sustain evening thunderstorms into the overnight hours. Some hail/wind risk could accompany the stronger storms. ...Smith.. 07/25/2023 $$ = = = 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) .