In areas where wind belts converge I'd say, considering they aren't limited to JUST storms.
The answer is recharged by precipitation
The Sahara desert is important for a multiple of reasons. One is that although it is a desert, there are many fertile areas of land making it great for farming and supporting life. It also acts as a natural barrier in between north and south Africa, which was able to impact trade with the South, slowing down innovation on both sides.
