Miami ? The fifth hurricane of an already deadly season developed in the open Atlantic Sunday, growing stronger as it moved over warm water but on a course expected to keep it away from land.

At 9 p.m. CDT, Hurricane Maria had maximum sustained winds of 85 mph, well over the 74 mph threshold for a hurricane.

The storm was centered 475 miles east-southeast of Bermuda and was moving north-northwest at 13 mph. It was expected to turn north today.

“On this track, Maria should remain well to the east of Bermuda and only pose a threat to shipping interests,” said Stacy Stewart, a hurricane specialist at the National Hurricane Center in Miami.

Maria’s hurricane force winds extend for 15 miles. The system is likely to strengthen before reaching the cooler water expected to sap its strength later in the week.

Maria is the 13th named storm of the Atlantic hurricane season, one of the busiest on record. Historically, only about four or five named storms form by this time of year, according to the hurricane center. Peak storm activity typically occurs from the end of August through mid-September.

The season began June 1 and ends Nov. 30.