MIAMI (AP) — The National Hurricane Center says Tropical Storm Gonzalo has formed in the Caribbean and could threaten Puerto Rico as a hurricane within days.

The center says the storm is currently centered about 200 miles east of the Leeward Islands with maximum sustained winds of 40 miles per hour. It is moving to the west at 10 mph.

Tropical storm warnings have been issued for the Leeward Islands.

Forecasters expect it to strengthen into a hurricane over the next couple days and could reach Puerto Rico by Tuesday as a Category 1 storm. A tropical storm watch has been issued for Puerto Rico and the Virgin Islands.

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