These amazing pictures from the United States show a wall of dust moving through the city of Phoenix in Arizona. Sandstorms like this happen during the region’s monsoon season, which is underway. They occur over desert land and can reach thousands of feet into the air, spurred by strong winds. The dense cloud dramatically reduced visibility, grounding flights at a major airport and leaving thousands without electricity. RT on Facebook: www.facebook.com/RTnews RT on Twitter: www.twitter.com/RT_com