This is the breathtaking moment a huge orange dust cloud towered over mountains in Arizona on Sunday evening (August 16).<br /> <br />The cloud emerged in the town of Gila Bend on the outskirts of Phoenix as temperatures soared to 115 degrees Fahrenheit.<br /><br />Onlooker Lori Grace is heard in the video saying the dust cloud is ''really pretty''.<br /><br />''I'm told this isn't the largest one people have seen, but it's definitely my first,'' she says.<br /><br />Drivers were caught up in the dust cloud as it caused low visibility on roads between Tucson and Casa Grande. The storm brought the traffic to a halt. <br /><br />Areas along interstate 10 south of Phoenix were slammed with the thick clouds of blowing dust, reducing the driving visibility, when it approached the valley at around 5:30pm.<br /><br />"The storm was so bad I had to stop at ELOY. My children were also frightened by the outside scenes" said Graham, one of the motorists caught in the dust storm.
