High confidence continues for a colder airmass to descend upon the Northern Rockies starting this Friday. The cold air could arrive in the Glacier Region between 5 and 11 am MST, and then into Grangeville by late evening. Snow could start as early as late evening Thursday. There is a 50 to 70 percent chance for greater than an inch of snow from the mountains of north-central Idaho into west-central Montana. The range of snowfall in the west-central Montana valleys go from a trace up to 4 inches. If snow showers are more robust and last longer Thursday night into Friday morning, then some locations may see locally higher amounts within that range. Gusty east winds ranging from 15 to 35 mph are expected with the arrival of the cold air on Friday. The higher wind speeds will be found in the channeled terrain and to the west of gaps like Badrock Canyon and Hellgate Canyon just to name a few. Be prepared for reduced visibility and slick areas on Friday into Saturday. The bright yellows in the snow probability image signify greater than 90 percent, or highest confidence for greater than 1 inch of snow.