Forecasters are tracking a new disturbance in the Atlantic Ocean as Hurricane Erin, a Category 5 storm, undergoes an eyewall replacement cycle, according to a Saturday night update from the National Hurricane Center.

Forecasters say Hurricane Erin has formed in the Atlantic Ocean on track to bring heavy rains that could lead to flooding and landslides in Puerto Rico and the Virgin Islands

Tropical Storm Erin is expected to become a hurricane later today, Aug. 15, and a Category 4 hurricane with maximum sustained winds of 130 mph over the weekend. A major hurricane is a Category 3 or stronger, with maximum sustained winds of at least 111 mph.

The National Hurricane Center expects this storm to gradually strengthen over the next day or so, but also warned of its potential to rapidly intensify within the next 24 to 48 hours.