An almost-opaque river of tan dust stretched hundreds of kilometers over China on April 28, 2005. The dust storm originated in the Gobi Desert near the border with Mongolia, blown by powerful winds across the Luliang Mountains, the peaks of which divide the tan cloud that filled the lower valleys, and blanketed the North China Plain. This is a highly populated region where several large cities, including Beijing, are located. This image of the storm was acquired by the Terra MODIS instrument on the morning of April 28. Such dust storms occur frequently in the spring when winds blow out of the north, and have been known to transport the dust all the way across the Pacific Ocean to North America.