It's not very often that the Sahara desert experiences these rainfall events. They are very rare, less than once per decade on average, but they are usually a sign that something is perhaps changing in the Earth's weather system, indicating an unusual state of the Atmosphere.
The driest place on Earth
Sahara is called the driest place on Earth because it receives little to no yearly precipitation. It is the world's largest and hottest desert, extending from the Atlantic Ocean in the west to the Red Sea in the east. It covers over 9.2 million square kilometers (3.6 million square miles).
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