Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Jul 26 2023 17:39:31 ACUS02 KWNS 261739 SWODY2 SPC AC 261737 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1237 PM CDT Wed Jul 26 2023 Valid 271200Z - 281200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF NEW ENGLAND INTO THE MID-ATLANTIC... ....SUMMARY... Widely scattered severe thunderstorms are forecast across southern New England southward into portions of the Mid-Atlantic states on Thursday. Damaging gusts and a couple tornadoes will be the primary hazards. ....Synopsis... A shortwave trough currently in the upper Midwest will continue eastward into Thursday. This feature is forecast to reach New England by early afternoon. Strong mid-level flow will persist across the northern periphery of the upper-level ridge in the northern Plains into the upper Mississippi Valley. A surface low will move through the Northeast along with an associated warm front and a weak front/surface trough trailing into the Blue Ridge/Piedmont regions. Another surface boundary in the northern Plains into northern Minnesota/Wisconsin/Upper Peninsula Michigan will sag southward. ....Northeast/Mid-Atlantic... Some ongoing activity is expected during the morning within the Northeast, likely near the Canadian border. Some lingering cloud cover can be expected perhaps into the early afternoon. Cloud cover will generally decrease with southward extent into the Mid-Atlantic. Heating through broken cloud cover in New England should be sufficient to promote at least 1000-1500 J/kg MLCAPE given the moist airmass expected. Deep-layer shear with the shortwave trough will not be overly strong (30-40 kts), but should allow for some storm organization with a mix of discrete cells and multicells. Low-level wind fields will be moderately strong and promote a risk for damaging winds with the strongest updrafts. Near the warm front, low-level shear will also favor some potential for low-level rotation and a threat for a couple tornadoes. Should greater surface heating occur, greater risk for damaging winds could be realized. Farther south into the Mid-Atlantic, weaker shear will be present. Stronger surface heating will still promote buoyancy perhaps in excess of 2000 J/kg MLCAPE. Damaging wind gusts and isolated large hail would be the main threats with activity moving off of the Blue Ridge. ....Central High Plains into Upper Midwest... Deep-layer shear will be maximized near the surface boundary and weaken with southward extent across the broad region. Scattered storms appear most likely within the higher terrain of Wyoming into eastern Colorado. These storms would primarily pose a threat of strong/severe wind gusts. Strong heating within the Plains could allow for isolated strong/severe storms to develop. Forcing will be weak and capping will keep storm development uncertain. Guidance does show a weak surface low developing in Minnesota into northwest Wisconsin. Surface convergence may be great enough to allow a cluster of storms to develop. Shear in this region would be favorable for supercells initially. Large hail and strong/severe wind gusts would be possible. Weak low-level shear and deep-layer shear parallel to the boundary, however, suggests upscale growth would occur relatively quickly and limit the duration of the large hail threat. ...Wendt.. 07/26/2023 $$ = = = 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) .