SAN JUAN, Puerto Rico — Dorian has hit the U.S. Virgin Islands just as it reached hurricane force, and forecasters say it could grow to Category 3 status before a likely collision with the U.S. mainland as early as the weekend.

The British Virgin Islands and the Puerto Rican islands of Vieques and Culebra were also in Dorian's path. Officials in the U.S. territory were worried the storm could bring landslides, widespread flooding and power outages in what could be the first major test of emergency preparedness since the 2017 devastation of Hurricane Maria.

Dorian prompted President Donald Trump to declare a state of emergency Tuesday night and order federal assistance for local authorities.

At 2 p.m. EDT, Dorian was located over St. Thomas in the U.S. Virgin Islands with maximum sustained winds of 75 mph (120 kph). It was moving northwest at 13 mph (20 kph).

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The change in the storm's course concerned many across the U.S. territory, where some 30,000 homes still have blue tarps as roofs nearly two years after Hurricane Maria. The island's 3.2 million inhabitants still depend on a shaky power grid that has remained prone to outages since it was destroyed by the Category 4 storm.

TS Dorian cone 8-28-19 5am
The cone of probability showing the probable path of Tropical Storm Dorian as of 5 a.m. EDT on August 28, 2019.
National Hurricane Center

Jorge Ortiz, a 50-year-old construction worker, was taking no chances. Wiping sweat from his brow, Ortiz climbed up a shaky ladder under a punishing morning sun and tied down pieces of zinc that now serve as his roof because Maria ripped the second floor off his house when it hit on Sept. 20, 2017.

He was forced to rebuild everything himself and finished just three months ago with no assistance from the local or federal government.

"They told me I didn't qualify because it was a total loss," he said, shaking his head as he added that he was wary. "I'm worried that despite all this sacrifice, I'll lose it again."

The U.S. National Hurricane Center issued a hurricane watch for Puerto Rico and a tropical storm warning for Puerto Rico, Vieques, Culebra and the U.S. Virgin Islands. A tropical storm watch was in force for the Dominican Republic from Samaná to Puerto Plata.

Dorian already caused power outages and downed trees in Barbados and St. Lucia, and a still-uncertain long-term track showed the storm near Florida over the weekend.

Although top government officials in Puerto Rico said they were prepared for the storm and had sufficient equipment, a couple of mayors, including those in the western region, said they did not have enough generators or shelters that were properly set up.

Jesús Laracuente, a 52-year-old construction worker who lives in the impoverished neighborhood of Las Monjas in the capital of San Juan, also had doubts about government preparations.

"The people here are prepared. We already learned our lesson," he said, referring to Maria. "What despairs us is knowing that the slightest breeze will leave us without power. It's the government that fails us."

José Ortiz, executive director of Puerto Rico's Electric Power Authority, acknowledged that the distribution system still has weak areas and could "suffer" under winds of 50 to 60 mph. However, he stressed the agency has the needed inventory, including more than 120,000 lights, 23,000 poles and 7,400 transformers.

But Freddyson Martínez, vice president of a power workers' union, told The Associated Press that while the electric grid has improved in some areas, he worries about a lack of power line workers and post-Maria patches which feature lines affixed to palm trees.

"Those are problems that are still being corrected to this day," he said. "These are the realities we have to face with this storm."

The island's transportation secretary acknowledged that crews are still rebuilding roads damaged or blocked by Maria, more than 1,000 of which remain blocked by that storm's landslides.

Puerto Rico Gov. Wanda Vázquez urged those living in flood-prone areas or under a blue tarp to move into one of the island's 360 shelters on Tuesday night. Housing Secretary Fernando Gil has said some 9,000 to 13,000 homes with blue tarp roofs are located in the region that Dorian is expected to affect the most.

Officials also said public schools and government offices would remain closed through at least Thursday.

"We learned our lesson quite well after Maria," Vázquez said. "We are going to be much better prepared."

Dorian was expected to move near the Turks and Caicos Islands and southeastern Bahamas on Thursday night or Friday.

Meanwhile, a new tropical depression formed Monday between the U.S. eastern coast and Bermuda. It was located about 315 miles (510 kilometers) southeast of Cape Hatteras in North Carolina and was moving north at 7 mph (11 kph) Tuesday with maximum sustained winds of 35 mph (55 kph). It was expected to become a tropical storm on Wednesday and continue blowing off the U.S. East Coast this week on a path to Canada's North Atlantic provinces.