10pm Update:
The National Weather Service has upgraded the northwestern counties in middle Tennessee to a Winter Storm Warning. (Areas in pink on the map below) In this area 2-4 inches of snow are possible. Remainder of the area remains under a Winter Weather Advisory where 1-3 inches of snow are possible. (purple areas on the map)
Forecast models have been trending up in the snowfall totals this evening. Forecast totals as of 10pm...
Snow has now begun to fall in western middle Tennessee...and as we put this update together was beginning to fall in the Nashville Metro area. (10pm)