First snow in the San Luis Valley usually shows on the San Juans a good while before it reaches the floor, a white line laid across the western horizon that everyone in Alamosa notices on the drive to work. Mark's Outdoor Sports, Inc. takes that as the signal and gets the blades ready. The work is plowing drives and lots, clearing walks, and treating the ice that forms where meltwater runs and refreezes overnight. Valley powder rides the wind, so piles go where the drift will not rebuild itself across an open drive. An outdoor shop knows what a cold morning asks of people; the least it can do is hand them bare ground to walk on.