Going into the weekend this was not on the radar. Things have evolved quickly this weekend. Favorable timing for accumulation. The timing with morning commute raises the impact. Should be mostly finished before noon on Monday.
All models have primary axis for snow across northern Illinois; through the Chicago area into lower Michigan. Short range models indicate the potential for 6, 7, or even 8" amounts locally in that area. In southern Wisconsin however we're looking at 3-5". A narrow gradient from 3-5", down to 1" or less is likely around the Wisconsin Dells area. Can't say I'm 100% confident I've put the gradient in the right place, it could end up further south.
NAM snowfall prediction through noon Wednesday
I was careful to keep Milwaukee in the 1-3". Models all show warmer temps along the lakeshore so I've reduced snow accumulations there.
Confidence is below average because of the quick escalation over the weekend and relative lack of run to run consistency, though the last couple runs have been trending this way. Little risky but gotta stick to our guns.
Lake effect continues in Upper Michigan. Another situation where with more time I would probably do a separate forecast. I'm satisfied with how the map looks and know folks in the area will be on top of it.
JP