The 8am EDT update from the NOAA National Hurricane Center placed Maria about 85 miles east of Martinique and about 120 miles east-southeast of Dominica.
It is moving at 12mph in a west-northwesterly direction.
Maria has now intensified into a category 2 hurricane with maximum sustained winds of 110mph, and is expected to strengthen rapidly during the next 48 hours as it reaches the Leeward Islands.
A Hurricane Warning has been issued for Guadeloupe, Dominica, St Kitts and Nevis, Montserrat, Martinique and St Lucia.
There is also a Hurricane Watch in effect for Puerto Rico, Vieques, and Culebra, the US and British Virgin Islands, Saba and St. Eustatius, St Maarten, St Martin, St Barts and Anguilla.