MIAMI (CBS4) – Forecasters at the National Hurricane Center say the system over the eastern Caribbean Sea has formed into Tropical Storm Rafael.

At 11pm, the storm is 185 miles south-southeast of St Croix, with top sustained winds of 40 mph. It is moving north-northwest at 12 mph.

The formation of the storm has prompted several island nations to declare a tropical storm warning.

Warnings have been issued for the U.S. and British Virgin Islands and numerous islands including Anguilla, Barbuda, St. Kitts, Nevis, Antigua, St. Maartin, Martinique and St. Lucia.

Puerto Rico is under a tropical storm watch.

The storm’s center will move through the eastern Caribbean on Friday night and then move near or over the Virgin Islands on Saturday or Saturday night. Rafael is expected to bring 3 to 5 inches of rain to parts, and slow strengthening is possible starting Saturday.

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