Well, looking at the 12Z and 18Z models, things seem to be going on track.
For the Great Lakes area...Trough swinging through during the afternoon, with CAPEs off modified ETA soundings for a more reasonable parcel of 83/68F indicates about 2750J/KG at 21Z. DTX and GRR seem to be "blowing off" the severe weather threat, particularly GRR, but I think quite the opposite (Actually, DTX goes on to mention how Monday looks like a bigger threat, and I don't see hardly any threat! - Moderate CAPE, light low level winds). For tomorrow...Low and mid level wind fields are between 30-50KNTS, with good directional shear in the lowest 0-3km, along the "warm front". Trough swings through in the afternoon/evening hours with good low/mid level RH and decent VV's, I see storms developing.
If one goes by the 18Z FSL DEV RUC, the Great Lakes would be in for a real treat, with CAPE approaching the upper 3000'sJ/KG, with a nice SFC wave developing along the trough...Which backs the flow a bit, and allows helicity to climb into the mid 400's. ETA shows no sign of this, but the FSL RUC does have better resolution, but I still think >3000J/KG CAPE is overdone, as well as the helicity.
I any case, the threat for severe thunderstorms looks pretty good tomorrow, with a decent potential for a few isolated tornadoes.
Robert
