Tropical Storm Erin continues to move quickly west, and is expected to become the first hurricane of the Atlantic season.

Tropical Storm Erin has formed on a path toward the Caribbean and is expected to strengthen to a hurricane later in the week as it passes by Puerto Rico. Most models forecast the storm turning upward into the Atlantic Ocean, but a few see the storm continuing onward to the U.S. mainland.

Tropical Storm Erin formed in the eastern Atlantic Ocean on Monday, forecasters said. The storm was expected to strengthen later in the week and could become the Atlantic's first hurricane of the season.