Story highlights Tropical storm watches are in effect for some islands affected by Hurricane Irma

Tropical Storm Lee forms in the eastern Atlantic but is likely to fade

(CNN) Tropical Storm Maria formed Saturday in the western Atlantic Ocean, prompting a hurricane watch for areas battered by Hurricane Irma last week.

Maria is about 590 miles east-southeast of the Lesser Antilles and is packing maximum sustained winds of 50 mph. The storm is moving toward the Caribbean at 19 mph, according to the National Hurricane Center.

Tropical Storm Maria forms in the Atlantic.

Maria is expected to gain strength through the weekend and become a hurricane by late Monday, forecasters said.

Tropical storm watches are posted for Barbados, St. Lucia, Martinique, Dominica and St. Vincent and the Grenadines. The hurricane watch covers Antigua, Barbuda, St. Kitts and Nevis, Montserrat and Guadeloupe.

Tropical Storm Maria is expected to become a Category 1 hurricane as it impacts the Caribbean.

That means areas devastated by Irma could again be dealing with hurricane conditions by Tuesday or Wednesday.

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