SAN JUAN, Puerto Rico (AP) — Elsa strengthened into the first hurricane of the Atlantic season on Friday as it battered the eastern Caribbean, where officials closed schools, businesses and airports, and it appeared headed eventually for Florida or the U.S. Gulf Coast.

Heavy rains and winds lashed Barbados as the Category 1 storm headed for islands including St. Vincent and the Grenadines, which are struggling to recover from recent massive volcanic eruptions.

Elsa was located about 75 miles (120 kilometers) east of St. Vincent and was moving west-northwest at 28 mph (44 kph). It had maximum sustained winds of 75 mph (120 kph), according to the National Hurricane Center in Miami.

“That level of sustained wind can blow down a lot of buildings and cause a lot of damage,” said St. Vincent Prime Minister Ralph Gonsalves. “I am pleading with you. Let us not take this hurricane lightly. This is not the time to play the fool.”

A hurricane warning was in effect for Barbados, St. Lucia and St. Vincent and the Grenadines.

The long-term track showed the storm rolling toward the Dominican Republic and Haiti as a hurricane before weakening back to tropical storm force and potentially heading in the direction of Florida by early Tuesday.

Authorities opened dozens of shelters in St. Vincent and urged people to evacuate if they lived near a valley, given the threat of flash flooding, mudslides and lahars, especially in the northern part of the island where La Soufrière volcano is located.

“Do not wait until it’s too late to go to a shelter,” Gonsalves said.

He said 94 shelters are open, a smaller number than in previous years because some 2,000 people remain in other shelters following massive volcanic eruptions that began in early April.

A tropical storm warning was in effect for Martinique, the southern coast of Dominican Republic from Cabo Engano to the border with Haiti and the entire coast of Haiti. A tropical storm watch was in effect for Grenada, Saba, Sint Eustatius, Dominica and Jamaica, while a hurricane watch was in effect for Haiti’s southern region from the capital, Port-au-Prince, to the southern border with the Dominican Republic.

Elsa is the earliest fifth-named storm on record, beating out last year’s Eduardo which formed on July 6, according to Colorado State University hurricane researcher Phil Klotzbach.

Elsa was expected to pass near the southern coast of Hispaniola, which is shared by Haiti and the Dominican Republic, on Saturday. The storm was then expected to move near Jamaica and portions of eastern Cuba on Sunday.

The storm was forecast to bring 3 to 6 inches (7 to 15 centimeters) of rain with maximum totals of 10 inches (25 centimeters) inches on Friday across the Windward and southern Leeward Islands, including Barbados. The rain could unleash isolated flash flooding and mudslides.