Simplify the following text for a Grade 9 native English-speaking person.
Original: On September 1 , the hurricane weakened to a Category 3 hurricane after an eyewall replacement cycle before becoming a Category 4 again .
Simplified: After moving away from the Leeward Islands , Earl was downgraded to a Category 3 hurricane due to changes in the eyewall of the storm . However , the hurricane quickly intensified back to a Category 4 .