An Atlantic disturbance now has a 50 percent chance of cyclone formation, according to the National Hurricane Center.

A tropical wave producing showers and thunderstorms is headed west-northwest across the tropical Atlantic. The system, which is currently moving along the eastern Atlantic, is expected to approach the Leeward Islands by the end of the week and could develop into a tropical cyclone.

Tropical Storm Erin -- which is forecast to strengthen into the first hurricane of the Atlantic season by Saturday morning -- won't have a direct impact on the U.S., but it will bring dangerous rip currents to the East Coast.