After knocking out power for hundreds of thousands of people in Puerto Rico, Hurricane Ernesto was strengthening in the western Atlantic on Wednesday, leading to a hurricane watch in Bermuda.

• Ernesto became a Category 1 hurricane on Wednesday, which means it has wind speeds of at least 74 miles per hour. It is expected to continue strengthening this week, and could become a major hurricane by Friday, according to the National Weather Service.

• A hurricane watch was issued for Bermuda, where hurricane conditions are possible by Saturday, the Weather Service said. The storm is not expected to approach the mainland United States, but forecasters warned it could cause life-threatening surf and rip currents along the East Coast by Thursday.

• President Biden approved a declaration of emergency in Puerto Rico, where nearly half of the customers served by the island’s utility were without power Wednesday. The power was also out for parts of the U.S. Virgin Islands.

Puerto Rico was bracing for up to 10 inches of rain in some areas, and power outages had been expected, given the island’s frail electrical grid. On Wednesday evening, Luma Energy, which transmits and distributes electricity in the territory, was reporting that more than 718,000 customers were still without power there.

Daryl Jaschen, the emergency management director for the U.S. Virgin Islands, which are east of Puerto Rico, said in a briefing late on Wednesday morning that the power was out across the entirety of St. John and St. Croix. There was some power being generated in St. Thomas, he said.

This hurricane season is expected to be busy.

Forecasters have warned that the 2024 Atlantic hurricane season could be much more active than usual.

Alberto, the first named storm of the Atlantic hurricane season, made landfall on the northeastern coast of Mexico as a tropical storm on June 20, unleashing heavy rain, flooding and gusty winds. At least four people died in events related to the storm.