By Ivelisse Riveria and Ezequiel Abiu Lopez

SAN JUAN, Puerto Rico/Santo Domingo (Reuters) – Hurricane Fiona made landfall in the Dominican Republic on Monday and Puerto Rico braced for another day of heavy rainfall and life-threatening flooding, a U.S. government agency said, one day after the island was hit by a widespread power outage.

The Dominican Republic is being battered with “extremely heavy rainfall” and winds as strong as 90 miles per hour, Eric Blake of the U.S. National Hurricane Center said, as storm conditions in Puerto Rico begin to subside.

Hurricane Fiona made landfall in Puerto Rico on Sunday afternoon, five years after the U.S. Caribbean territory was ravaged by Hurricane Maria.

“Tomorrow will be dryer than today, but it will be a long day today,” said Blake, acting branch chief of the NHC’s hurricane specialist unit. “The strongest winds are already dying down and it’s already over the Dominican Republic.”

The eye of the storm made landfall in the Dominican Republic near Boca Yuma at 3:30 a.m. local time, the NHC said.

Nearly 90% of Puerto Rico remained without power on Monday, according to Poweroutage.us. Officials said it would take days to reconnect the whole island of 3.3 million people.

U.S. President Joe Biden approved an emergency declaration for Puerto Rico on Sunday, authorizing the Federal Emergency Management Agency to coordinate disaster relief and provide emergency protective measures.

Puerto Rico’s grid remains fragile after Hurricane Maria in September 2017 caused the largest blackout in U.S. history.

In that Category 5 storm, which killed more than 3,000 people, 1.5 million customers lost electricity with 80% of power lines knocked out. Thousands of Puerto Ricans still live under makeshift tarpaulin roofs.