Hurricane Erin has rapidly intensified into a category five hurricane, packing maximum sustained winds of 160mph (260km/h).
National Hurricane Center Director Mike Brennan told a briefing that the "extremely powerful" storm had "explosively deepened and intensified" overnight after growing from tropical storm strength on Friday.
Erin is expected to pass north of the Leeward Islands, the Virgin Islands and Puerto Rico over the weekend, bringing up to 6in (15cm) of rain, with the potential for flash flooding and mudslides.
The storm, which is the first hurricane the 2025 Atlantic season, is not currently forecast to make landfall on the mainland US.
Hurricane Erin underwent rapid intensification, in which a storm strengthens by at least least 34mph in a 24-hour period.
