Subj : DAY2SVR: Slight Risk MW To : All From : Mike Powell Date : Mon Feb 26 2024 07:58:00 ACUS02 KWNS 260638 SWODY2 SPC AC 260637 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1237 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, and southwestern Great Lakes. ....Mid-MS Valley/Southwest Great Lakes Vicinity... An upper trough over the northern Rockies/Intermountain West will shift east on Tuesday, becoming oriented from the Upper MS Valley and Mid-MO Valley by Wednesday morning. Fast deep-layer southwesterly flow ahead of this feature will overspread the Ozark Plateau into the Great Lakes. At the surface, a low will deepen as it shifts east from MN toward southern Ontario. A cold front attendant to the low will quickly shift east/southeast across the Plains and the Mid/Upper MS Valley during the afternoon and into the overnight period. Initial thunderstorm activity may develop in warm advection regime near the quasi-warm front/moisture gradient from northern IL into IN/NW OH/southern MI around 21-00z. Additional activity will then develop along the cold front as it develops east and the main upper wave ejects into the region around 00-03z. Warm advection and southerly low-level flow ahead of the front will allow for modest airmass modification into the Midwest. However, forecast dewpoints are only expected to reach into the 50s to near 60 F. Nevertheless, a plume of steep midlevel lapse rates will overspread the IL/IN/MI/OH vicinity from afternoon into the evening. This will support modest destabilization with MLCAPE generally forecast to be less than 1000 J/kg, though a narrow corridor of up to 1500 J/kg MLCAPE may be possible for a brief period around 00z. Forecast soundings across the region indicate most of available instability will be located above the 850-700 mb layer. Initial thunderstorm activity may be slightly elevated as some forecast soundings indicate a warm nose between 850-700 mb during late afternoon/early evening. Nevertheless, effective shear greater than 50 kt, and enlarged low-level hodographs becoming elongated above 3 km indicate initial supercells will be possible near the quasi-warm front/moisture gradient from northeast IL into northern IN and vicinity. With most instability focused above the 850-700 mb layer, and in conjunction with poor boundary-layer dewpoints, the tornado risk may be somewhat lower than typically expected given shear profiles in the 0-2 km layer. Nevertheless a couple tornadoes are possible, especially if greater moisture than forecast can make it this far north. Large hail, with a few instances near 2 inch diameter, will be possible with any semi-discrete supercells, along with damaging gusts. Once linear forcing along the front increases in the 00-03z period, a line of storms is forecast to develop east from the Mid-MS Valley toward the Lower OH Valley during the nighttime hours. Damaging gusts will be the main concern with this activity. ...Leitman.. 02/26/2024 $$ --- SBBSecho 3.14-Linux * Origin: ILink: CCO - capitolcityonline.net (454:3/105) .