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DEC 13, 2017 | 10" in Sturgeon Bay Wisconsin

Alberta clipper in dynamic upper level flow. Moisture starved initiatlly but increasing in coverage throughout the day. From the start it was clear the main snow band was key to snow accumulation with a sharp cutoff in snow accumulation to the south of that. Initial model runs had the snow band position along an axis from Stevens Point to Sheboygan. This band was dependent on 700mb forcing and the timing had to be right as the clipper moved quickly. The night prior to Wednesday 12/13, a northward shift occurred in the main snow band. This hung the lower end of weather advisories out to dry. However snow accumulations over-performed the 3-6" forecast in northeast Wisconsin due to conservative expectations that were more in line the average alberta clipper. This was stronger than the average clipper. This is where I learned to bump up snow predictions in northern Wisconsin just because.