Unfortunately for Twin Cities snow lovers, the majority of moisture from tomorrow’s system will probably miss the core of the metro. But perhaps not by much, depending on which model is more correct.
Both the GFS 12Z run and the 18Z NAM run just coming out are showing multiple precipitation bands with the system coming through tomorrow. The GFS shows a couple primary bands, one in NW Minnesota and one in extreme SE Minnesota (over Rochester), and gives the Twin Cities metro only 1-2 inches of snow (if even that much), mostly during the morning hours tomorrow. Also, both models indicate a possibility for a little freezing precipitation before sunrise, transitioning to all snow during the morning rush.
The 18Z NAM model has 4 SW-to-NE oriented bands of precipitation over Minnesota as shown in the graphic below. If the NAM forecast is accurate, the SE corner of the metro could get up to six inches of snow in a very narrow band, perhaps only 10-20 miles wide, but with a sharp cutoff on the NW side, such that the NW metro would get only 1-2 inches.
Of course, perhaps the GFS is correct, and we’ll get at most 1-2 inches over the east metro and even less on the west side. Modeling snow amounts is obviously not an exact science, so anyone in the metro probably needs to be prepared for anywhere from 1-6 inches. I’m not proud of a prediction range this wide, but I think with the uncertainty of the modeling tools we have, we can’t be any more precise with this particular system.