Snow covers the Sapphire Mountains Sunday afternoon under a clear sky in the Bitterroot Valley.

Though colder than last week, western Montana didn't receive the full effect of the large cold front that came down out of the Arctic. The temperatures in the Hamilton area were dipping down into the single numbers Sunday night, but were forecast to rebound Monday evening.

Eastern Montana caught some of the cold blast that was called a 'polar vortex' and affected almost half of the American continent. Sunday morning temperatures were down to 9 below zero in Bismarck, N.D., and minus 21 at Duluth, Minnesota.

The system also included about a foot of snow in the middle of the nation.