Subj : MESO: Mesoscale Discussion 1254 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Jun 25 2023 17:11:48 ACUS11 KWNS 251711 SWOMCD SPC MCD 251710=20 MIZ000-251915- Mesoscale Discussion 1254 NWS Storm Prediction Center Norman OK 1210 PM CDT Sun Jun 25 2023 Areas affected...Portions of Lower MI Concerning...Severe potential...Watch likely=20 Valid 251710Z - 251915Z Probability of Watch Issuance...80 percent SUMMARY...An increasing threat for scattered damaging winds, large hail, and perhaps a couple of tornadoes will likely warrant watch issuance this afternoon. DISCUSSION...As an upper trough/low advances eastward across the Upper Midwest, convection has developed across southeastern WI/far northeastern IL/far northwestern IN. There is still remnant cirrus from prior convection extending northward across much of Lower MI, which has slowed diurnal heating to some extent. But even with this cloudiness, temperatures have generally reached into the lower to mid 80s. Low-level moisture is forecast to continue streaming northward across this region over the next few hours, which should further aid in gradual boundary-layer destabilization. Much of southern Lower MI will remain to the north of a 50+ kt mid-level jet across the OH Valley. Still, there will probably be enough deep-layer shear for some thunderstorm organization, with a mix of multicells and supercells possible. Large to very large hail may be the primary severe threat with initially discrete convection. Upscale growth into a cluster seems probable as convection spreads eastward across Lower MI this afternoon and early evening. Severe/damaging winds will become an increasing concern as this mode transition occurs. Some threat for a tornado or two may also exist mainly across far southern Lower MI, as low-level shear gradually increases. ...Gleason/Grams.. 06/25/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!5WThCJpHJO9Jx9H4hZpIC3UAJLPqFWtR2mADGOvGzruvIEKNx-XW_nwn-eceSrOahutG0xqjD= 6nEJu56GhU4WXNqY1s$ for graphic product... ATTN...WFO...APX...IWX...GRR... LAT...LON 43788668 44328618 44238469 43498461 42788439 42148464 41988617 42228681 43148691 43788668=20 =3D =3D =3D 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) .