Hurricane Erin strengthened into a Category 2 storm on Friday as it approached the northeast Caribbean, prompting forecasters to warn of possible flooding and landslides.

Erin became a Category 3 hurricane in the Caribbean early Saturday and is expected to strengthen further during the day, the U.S. National Hurricane Center reported.

This type of explosive strengthening is happening more frequently as planet-warming pollution tips the scales toward hotter oceans that fuel powerful storms.