Precipitation will combine with below-freezing surface temperatures in the lower atmosphere to create an environment possibly favorable for some falling snowflakes. Very little, if any, accumulation is expected, making the intensity rating a '1'.
Midwest, 3-4 Days
Lake effect showers in the Upper Midwest will be occurring in sub-freezing temperatures in the 850mb layer. When that layer is below freezing, the surface can be as well. However, due to the tendency of unpredictability with lake effect showers, this gets a 'Medium' confidence rating.
Forecast was made September 21, 2012.