The collapse of a mid-afternoon, multicellular thunderstorm cluster in the Sacramento Mountains (to the east) sent a magnificent outflow arc across the Tularosa Basin, including White Sands National Monument. The outflow winds were strong enough to whip grains high off the dunes, reducing visibility and getting into eyes, hair and clothes, even as these were no ordinary “sand” particles. These dunes are composed not of quartz, as with true sand, but of a salt known as gypsum—the hydrated form of calcium sulfate. Gypsum here washed off the San Andres Mountains, faintly seen in the western background, in huge quantities. It then dried out of solution in the basin’s lakebed, and was rendered granular and shaped into dunes by eons of wind action.
19 WSW Alamogordo NM (18 Jun 19) Looking W
32.8199, -106.275Outflow across White Sands
The collapse of a mid-afternoon, multicellular thunderstorm cluster in the Sacramento Mountains (to the east) sent a magnificent outflow arc across the Tularosa Basin, including White Sands National Monument. The outflow winds were strong enough to whip grains high off the dunes, reducing visibility and getting into eyes, hair and clothes, even as these were no ordinary “sand” particles. These dunes are composed not of quartz, as with true sand, but of a salt known as gypsum—the hydrated form of calcium sulfate. Gypsum here washed off the San Andres Mountains, faintly seen in the western background, in huge quantities. It then dried out of solution in the basin’s lakebed, and was rendered granular and shaped into dunes by eons of wind action.
19 WSW Alamogordo NM (18 Jun 19) Looking W
32.8199, -106.275