Tropical Storm Ernesto was poised to become a hurricane shortly after brushing past Puerto Rico late Tuesday as officials closed schools, opened shelters and moved dozens of the U.S. territory's endangered parrots into hurricane-proof rooms.

Ernesto is forecast to become a hurricane overnight as the center of the storm moves just northeast of Puerto Rico on a path toward Bermuda. Forecasters issued a hurricane watch for the U.S. and British Virgin Islands as well as the tiny Puerto Rican islands of Vieques and Culebra, which are popular with tourists.

“Since there is some chance of Ernesto becoming a hurricane while it is near the Virgin Islands, a hurricane watch remains in effect,” the U.S. National Hurricane Center in Miami said.

The storm moved over the U.S. Virgin Islands on Tuesday night. After passing Puerto Rico, it is expected to move into open waters and be near Bermuda on Friday.

Heavy rains began pelting Puerto Rico, and strong winds churned the ocean into a milky turquoise as people rushed to finish securing homes and businesses.

“I'm hoping it will go away quickly,” said José Rodríguez, 36, as he climbed on the roof of his uncle's wooden shack in the Afro-Caribbean community of Piñones on Puerto Rico's north coast to secure the business famous for its fried street food.

Ernesto was about 60 miles (95 kilometers) east-northeast of San Juan, Puerto Rico late Tuesday night. It had maximum sustained winds of 65 mph (100 kph) and was moving northwest at 17 mph (28 kph).

“We are going to have a lot of rain,” Puerto Rico Gov. Pedro Pierluisi said as he urged people to be indoors by early Tuesday evening.

He activated the National Guard as crews across the island visited flood-prone areas and older residents as part of last-minute preparations. Meanwhile, Department of Natural Resources officials who work at breeding centers for the island's only remaining native parrot, the Puerto Rico Amazon, moved them indoors.

Ernesto Rodríguez with the National Weather Service warned that the storm's trajectory could change as it approaches Puerto Rico.

“We should not lower our guard,” he said.

As intermittent rain pelted Puerto Rico's northeast, residents in Piñones tried to squeeze in a couple more hours of work.

María Abreu, 25, prepared fried pastries stuffed with shrimp, crab, chicken and even iguana meat as she waited for customers.

“They always come. They buy them in case the power goes out,” she said.

Down the road, Juan Pizarro, 65, picked nearly 100 coconuts from palm trees swaying in the strong breeze. He had already secured his house.

“I'm ready for anything,” he said.

Forecasters have warned of waves of up to 20 feet (six meters), widespread flooding and possible landslides, with six to eight inches (15-20 centimeters) of rain forecast for Puerto Rico and the U.S. Virgin Islands, and up to 10 inches (25 centimeters) in isolated areas. Puerto Rico has six reservoirs that already were overflowing before the storm.

Officials in Puerto Rico warned of widespread power outages given the crumbling electric grid, which crews are still repairing after Hurricane Maria razed it in September 2017 as a Category 4 storm.

Juan Saca, president of Luma Energy, a private company that operates the transmission and distribution of power in Puerto Rico, urged people to report blackouts: “Puerto Rico's electrical system is not sufficiently modernized to detect power outages.”

Outages also were a concern in the neighboring U.S. Virgin Islands for similar reasons, with blackouts reported on St. Thomas and St. John on Monday.

“Don't sleep on this,” said U.S. Virgin Islands Gov. Albert Bryan Jr., whose administration announced early Tuesday that it was closing all schools.

The U.S. Federal Emergency Management Agency echoed those warnings, saying residents in Puerto Rico and the U.S. Virgin Islands “should be prepared for extended power outages.”

Early Tuesday, Ernesto drenched the French Caribbean island of Guadeloupe, where officials closed several main roads and warned that the quality of potable water would be affected for several days. Meanwhile, the storm downed a couple of trees in Antigua, and knocked out power to most of the island. Ernesto also forced the cancellation of dozens of flights to and from Puerto Rico.

Ernesto is the fifth named storm of this year’s Atlantic hurricane season.

The National Oceanic and Atmospheric Administration has predicted an above-average Atlantic hurricane season this year because of record warm ocean temperatures. It forecast 17 to 25 named storms, with four to seven major hurricanes of Category 3 or higher.