The municipality lies on the northeastern side of the Saltfjellet mountains, in the rain shadow of the mountains. With mountains surrounding it in almost all directions, Saltdal is one of the driest areas in Norway, especially the upper part of the valley. For five years in a row, 2001 to 2005, and then again in 2007 and 2008, the weather station in the upper part of the Saltdal valley recorded the least precipitation in all of continental Norway, with only in 2005. Average annual precipitation is per year in the upper part of the valley.