Simplify the following text for a Grade 5 native English-speaking person.
Original: It struck Galveston and Houston , Texas directly , causing $ 2.6 billion USD ( $ 5.27 billion 2006 USD ) in damage and killing 21 people ; this made it the worst Texas hurricane since Hurricane Carla ( 1961 season ) , and Texas ' first billion-dollar storm .
Simplified: In the end , Hurricane Alicia killed 21 people and caused $ 2 billion in damage ( $ 5.27 billion in 2006 dollars ) .