Here is the first snow map this clipper/strong low pressure system. Two storms will merge around northern Illinois and create enough lift to drop up to a foot of snow in spots. The problem is an area of high pressure in Ontario that will keep off some of the snow from moving east. The question is how long will the high pressure hold and how far east will the heavy band get. A few days ago high pressure appeared to win out, and the heaviest snow looked to fall in Iowa, however new data has led to the consensus on the left. The are winter storm watch and warnings postedfrom North Dakota to Illinios. I would expect them to get expanded to the east as we get closer to the system and confidence of the weakening high pressure falls apart. Notice how narrow the band is, giving even less room for error. Later today should shed more light on this system, and look for an update later this afternoon/evening. Simply said confidence is not complete, so check back later for an even more concrete forecast
