A large wave of Saharan dust making its way across the Atlantic Basin is forecast to arrive in the U.S. later this week, impacting the Southeast with hazy skies and "dirty rain."

Every summer, strong winds blow massive clouds of dust off the Sahara Desert in Africa. This is called the Saharan Air Layer, or SAL. These dust clouds ride the wind across the Atlantic Ocean, sometimes traveling more than 5,000 miles all the way to Florida.