7/24/10 FCST: MI/OH

[Andrew Herron]

I'm sure more states will be added...

I'm not an expert on reading the models, but from what I can tell, the 00z NAM and GFS are too far North right now with the convection that has popped up along Illinois. The 02z HRRR seems to show the potential for fog to not be a concern at 17z so the main development appears to be along or south of I-94. Toledo looks to be under the gun here as that's where the helicity and real juicy dew points are, but I have reservations about it being that far south.

It's hard to pin down timing but I'm going to take a stab and say we'll see initiation around 18z.

Feel free to help me out and point out any holes or perhaps other maps I can look at to get a better idea of what's up.

 

[Robert Dewey]

It's not looking too good for MI. What's moving through right now is pretty much the main action, which should trigger new convection along / SE of it after 19z from NE OH into central IN... Just south of the MI border. Behind this convective mess, temps have dropped into the low 70s across northern MI right ahead of the cold front... compared to parcels of 84/+77 found in IN and southern IL. I'm quite confident we won't destabilize in time, pretty much wiping out SVR chances in MI.

 

[John Farley]

I'm going to be keeping my eye on central IL later this afternoon. RUC is predicting extreme instability there, CAPE in the 5000-6000 range shifting eastward into central IL from northern MO. Directional shear is not very good, but there will be decent speed shear, so if those forecasts of instability verify, things could get a bit interesting there. I agree with Robert that most of the action will probably be farther south than Michigan.

 

[John Vandehei]

I'm not ready quite ready to write Michigan off just yet, although I agree with Robert - it's not looking good. However, the convective mess that moved across the region is weakening quickly and breaking up. Already, I'm seeing blue sky to my south and west. This time of year, it doesn't take too long to destabilize - a few events in the past week or so I've seen areas under the clouds most of the day and then rapidly destabilize with only about 2 hours of sunshine. The latest NAM does try to push CAPE's approaching 4000 J/Kg into the southern two rows of counties in southern Michigan. However, the RUC keeps the good instability just south of the MI/IN border. Unfortunately, a recent glance at SPC's mesoanalysis page shows the RUC to be more on target for now in terms of instability. Right now, I'll hang on to some cautious optimism that something could pop up in Michigan, at least south of I-94. I do agree that northern IL and IN look like the best bets right now.