Dust storms blowing out of the Sahara Desert in northern Africa are quite common, and from November to February every year are often driven by the harmattan winds. These winds interrupt the NE trade winds in the North African Atlantic, and often appear yellow from the dust they carry. This true-color Terra MODIS image from January 7, 2005, shows a large cloud of dust blowing east over the Atlantic as far as the Cape Verde Islands, the northernmost of which are visible in the lower left corner. At the upper right, the southern Canary Islands are also visible.
Note: Often times, due to the size, browsers have a difficult time opening and displaying images. If you experiece an error when clicking on an image link, please try directly downloading the image (using a right click, save as method) to view it locally.