The quake hit at 11:23 p.m. local time, striking 49 miles off the island’s northwest coast, the U.S. Geological Survey said, and was followed by a series of smaller aftershocks.
Elmer Román, Puerto Rico’s secretary of public safety, said on Tuesday morning that there were no reports of injuries or any significant damage. Local news outlets reported a water pipe broke in Mayagüez, in western Puerto Rico.
Authorities were already on alert as Tropical Storm Karen loomed to the south of the island, where up to 30,000 survivors of Hurricane Maria are still living under leaky tarps.
With winds likely to hover around 45 mph, Karen bears little resemblance to Maria, which devastated the island two years ago when it was nearly a Category 5 hurricane, with winds of 155 mph. Hurricane Dorian, this season’s only major storm so far, also mostly spared the island.
But National Weather Service officials warned that the destructive potential of Karen should not be underestimated, even at lower wind speeds.
“People are saying, ‘It’s just a tropical storm,’ but there’s no such thing as ‘just a tropical storm,’” said Dennis Feltgen, a meteorologist with the National Hurricane Center in Miami. “Tropical storms can create a lot of havoc.”
In Puerto Rico, emergency managers urged local mayors to prepare for rain and flash flooding, especially on the eastern side of the island and in the island municipalities of Vieques and Culebra, which are between the big island and the U.S. Virgin Islands.
“Weather conditions are going to worsen,” Gov. Wanda Vázquez cautioned as she urged Puerto Ricans to get off the roads and out of rough seas and rising rivers. Employers, she said, should let workers stay home.
Meteorologists from the National Weather Service office in San Juan, the capital, said that the rain could continue in parts of Puerto Rico into Wednesday.
The combination of the storm and the lingering effects of Hurricane Maria was already posing logistical problems.
Vieques has been without a fully functioning hospital since Hurricane Maria destroyed the island’s public medical facility in 2017. So when a newborn on Vieques got sick Tuesday morning, the Puerto Rico National Guard had to be called on to fly the baby to a hospital on the big island, Vázquez said.
A 15-year-old girl also had to be medevaced from Vieques on Monday night, said Rafael Rodríguez Mercado, the health secretary.
The core of Tropical Storm Karen, which slowed down overnight, was expected to arrive Tuesday afternoon, but the worst rains will hit after the center moves over the island. Isolated areas, especially in Puerto Rico’s central mountainous region, could get more than 6 inches of rain. Those conditions could create life-threatening mudslides, officials warned.
Sixty-seven shelters opened in some vulnerable communities.
“Puerto Rico is prepared,” Vázquez said.
Ferries from the big island to Vieques and Culebra were suspended Monday evening. Schools and government offices remained closed Tuesday. Vázquez signed an executive order freezing fuel prices to prevent gouging.
Power still goes out — if only briefly — on a regular basis in parts of Puerto Rico, where the electrical grid remains frail. But the public power utility is better prepared to respond to any possible outages than it was during Hurricane Maria in 2017, the governor said.
An average hurricane season, which lasts from June to November, has 12 named storms, a designation given to storms with winds that reach 39 mph, said Feltgen of the National Hurricane Center. Of those, an average of six become hurricanes, with winds of at least 74 mph, and three become a Category 3 or above, with winds over 111 mph.
This year, 12 storms have been named, four have become hurricanes and one, Dorian, became a Category 5, wreaking catastrophic devastation in the Bahamas.
“We’re pretty close to an average season,” Feltgen said. “But we still have a little more than two months of the hurricane season to go.”
This article originally appeared in
.