A very powerful Hurricane Maria, and fragments of Tropical Storm Jose, on Wednesday were pummeling parts of the National Park System from the Virgin Islands to Cape Cod.

While Maria was downgraded early Wednesday from a Category 5 to Category 4 hurricane, with winds below 170 mph, the National Hurricane Center stressed that "Maria remains an extremely dangerous hurricane. Some weakening is likely while the system crosses Puerto Rico. Later in the forecast period, less favorable upper-level winds should cause further weakening, but Maria is likely to remain a large and powerful hurricane for the next 5 days."

Maria was not expected to make a direct hit on Florida, where cleanup operations were ongoing from Dry Tortugas National Park north, but rather swing to the east of the state. But in the U.S. Virgin Islands, Virgin Islands National Park on the island of St. John was being hammered by the storm. National Park Service staff on the mainland had no updates on the latest storm impacts to Virgin Islands National Park; all they could report was that all Caribbean units of the park system were closed.

Along the Eastern Seaboard, rough surf conditions and dangerous rip tides were in the forecast for Fire Island National Seashore north to Cape Cod National Seashore. At Fire Island, recreational beach driving and backcountry camping were closed due to Jose.

"While the center of Jose is forecast to remain offshore of the U.S. east coast, the large cyclone is expected to cause some direct impacts in portions of New England, and a tropical storm warning is in effect for Cape Cod, Block Island, Martha's Vineyard, and Nantucket," the Hurricane Center reported Wednesday morning. "Minor to moderate coastal flooding is possible from Delaware to southern New England during the next several days."

At Cape Cod National Seashore, staff warned that Jose "will bring high winds, big waves, and rain. Stay back from bluffs and dune bases. Don't turn your back on the ocean."