Tropical Storm Erin has officially formed in the Atlantic, and it could become the first hurricane of the season. The tropical storm formed on the morning of Monday, Aug. 11, and has maximum sustained winds near 45 mph, according to a public advisory from the National Hurricane Center (NHC) in Miami.

A hurricane might form in the Atlantic Ocean by the end of this week, according to the National Weather Service. The storm, which would be named Hurricane Erin, has a 90% chance of becoming a cyclone within the next seven days.

Forecasters say Tropical Storm Erin has formed in the eastern tropical Atlantic Ocean as Hurricane Henriette is strengthening in the Pacific Ocean.