Hurricane Erin became a Category 4 storm in the Caribbean early Saturday and is expected to strengthen further during the day, the National Hurricane Center reported.

Heavy rains were forecast to start late Friday in Antigua and Barbuda, the U.S. and British Virgin Islands and southern and eastern Puerto Rico.

Erin is expected to become a hurricane Friday, Aug. 15 and a major hurricane by Sunday morning. What Florida can expect from the storm.