Puerto Rico is quickly sloping toward a Katrina-level catastrophe. A week after Hurricane Maria made landfall, the power is off nearly island-wide. Food and supplies critical for keeping 3.5 million people — a higher population than in 21 U.S. states — alive and well, are running out fast.

“There will be a humanitarian crisis,” Puerto Rico Governor Ricardo Rosselló said Tuesday morning on CNN in a plea for the federal government to send more help to the island. “There will be massive exodus to the United States.”

The U.S. territory evaded the worst that Hurricane Irma had to offer before absorbing a hit from Maria a week later. It would have been a crushing blow to any place where a Category 4 hurricane might have made landfall, but Puerto Rico was in a particularly precarious position for a number of reasons, including its status as an American commonwealth, its recent economic woes, and (you guessed it) climate change.