LOL... I started a thread on this topic the same time you did - I deleted it though... Here is my original post -
Looks like a decent threat for severe thunderstorms tomorrow afternoon through tomorrow evening/night. Very intense low pressure system will move eastward - North of Lake Superior during the day (988MB), with a very strong front swinging through the region. Latest ETA suggests that moisture should pool along and ahead of this front, as it becomes somewhat semi-stationary. Forecast soundings from lower MI look VERY impressive as far as speed shear is concerned, with 50knts making down to 9K-10K FT... Combined with a little directional shear in the 0-3KM layer puts helicity to near 200M2/S2. Low level and bulk shear paremeters would suggest that supercells would be a very real threat, but given the fact that the upward motion is situated in a linear fashion and SFC convergence (which is also very intense) is strongly linear, storms should form into a single line (But as usual, nothing can be ruled out). ETA suggests storms will roll through southern MI between 21Z WED and 03-06Z THU from west to east (generally), with instability still at or near 1500J/KG through the night time hours, which would likely sustain a line of thunderstorms.
This event looks like it has the potential to be a hybrid derecho event (widespread wind event, containing properties of both serial and progressive events - Such as May 31 1998), given the length/strength of the forcing along the front, very intense wind fields (especially for August!), strong height falls, very strong dry air intrusion between 500-300MB... Only real thing missing is monster CAPE values.
We shall see
Robert