29. Major Winter Storm moving towards Great Lakes.
Current surface analysis shows a low pressure forming over the Oklahoma/Texas panhandles (1001 mb) and the models show it strengthening and moving northeast at a pretty good clip.
This HPCmap (to the right) shows the models' forecast path of the low pressure, I have added the times in colored text that corresponds to the model's placement colors.
Heavy snow possible from Iowa through northern Michigan.
This map (to the left) shows current watches, warnings, and advisories across the US from the SPC.
A swath of Winter Storm Watches extend across the Midwest, following the path of highest expected snowfall. Amounts in these areas could range from 4 to 12 inches by Monday. In addition, the storm system is currently bringing severe weather to Texas tonight - the blue box is a Severe T-Storm Watch and the red is a Tornado Watch.
A low in southern Canada will play into this too.
Moving from Saskatchewan into Ontario there is a weak northern system (1004 mb) that has been gaining a little steam. This low pressure is visible on the map from WUnderground.com (to the right). It has brought a warm front across the region, allowing most of us to rise above freezing briefly this afternoon.
This northern low has also brought the warmth to the upper areas of the atmosphere, so as light precipitation overtakes the region tonight, it will begin as light freezing rain or sleet before turning over to light snow.
Both the southern system and the northern one will begin to merge together late tonight. As they do so, the northern low will drag a cold front across the area Sunday evening.
So where will the snow fall?
This graphic from the HPC (for Sunday) that shows probabilities of where the heaviest snow will fall. Once the math is done, the greatest chance lies within the red circle across southern & eastern Wisconsin and northern Michigan.
Here on the hill (on the Bayfield Peninsula) I probably won't see any heavy snowfall. However, the NWS in Duluth has issued Winter Storm Watches for Ashland and Iron Counties for possible lake-effect snow behind the cold front. My current forecast calls for between 1 and 3 inches by Sunday evening, the lake-effect snow looks like it will miss me completely.
Heavy snow possible from Iowa through northern Michigan.
A low in southern Canada will play into this too. 
So where will the snow fall?