James Gustina
Supporter
The GFS and ECMWF have both been pointing at a potent longwave riding over the top of the high pressure dome and gradually digging into the upper Great Lakes region. The moist air mass that is currently squatting over the Great Lakes/Ohio River Valley should be untouched for the most part going into Friday. Dews will probably be sitting in the lower 70s throughout most of the warm sector. Right now the GFS has been spitting out SBCAPE values aoa 3000 j/kg across northern Indiana and Ohio but I'm not trusting it's solution for the thermodynamic environment because of the number of factors (leftovers from the night before and heavy cloud cover) that could dampen that value. The other issue is how far the jet will be sinking down, with both the GFS and Euro keeping the bulk of better upper-level support further north into Central Michigan. The uniform shear profiles ahead of the front will probably support linear segments but this day bears an uncanny resemblance to other recent derecho days, but a derecho is still questionable because of both the thermodynamic environment further north and the weaker speed shear.