 The depression gradually strengthened as it moved to the northwest across the open Atlantic Ocean, becoming Tropical Storm Maria on September 2 and reaching hurricane strength on September 4.In the central Atlantic, Hurricane Maria continued to strengthen in favorable conditions, and on September 5 briefly became a Category 3 hurricane with 115 mph (185 km/h) winds while 480 miles (770 km) east of Bermuda.Increasing shear and cooler waters caused the storm to rapidly weaken to a minimal hurricane on September 7.