The Ocean City Beach Patrol has closed the ocean to swimming, wading and surfing Tuesday as tropical storm activity off the coast brings dangerous conditions to the resort town.

Hurricane Erin has been downgraded to a Category 3 hurricane but is gaining in size and raising the risk of life-threatening surf later this week along the U.S.

Hurricane Erin is a huge Category 4 storm and is expected to both grow larger and stronger today as it moves toward the west-northwest. The center of the storm is expected to remain offshore as it moves between the U.S. and Bermuda.

Two more tropical systems trail Hurricane Erin, which is following a projected course that brushes past the East Coast without making landfall.

Hurricane Erin weakened to a category 3 hurricane during the early hours of Aug. 19 as it moves closer to the East Coast, according to the National Hurricane Center.

Hurricane Erin was a Category 4 storm with 130 mph winds on Monday night as it passed to the east of the Bahamas. The forecast track keeps the center of the storm well away from the U.S. East Coast this week, but tropical storm and storm surge watches have been issued for the North Carolina Outer Banks. National Hurricane Center

Hurricane Erin is expected to brush the coast of North Carolina on Wednesday, forcing officials to issue warnings and evacuation notices.

The storm will remain a major hurricane through the middle of the week, according to the National Hurricane Center.