Tropical Storm Dorian expected to strengthen to hurricane

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PUERTO RICO — Tropical Storm Dorian has formed in the Atlantic and is expected to strengthen to a Category 1 hurricane.

[NEW: Caribbean islands bracing for impact as Tropical Storm Dorian strengthens]

The storm is nearly 500 miles east of St. Lucia,

The storm is expected to bring wind and rain to the Caribbean islands and Puerto Rico over the next week.

Severe Weather Team 2 Meteorologist Katie Walls said the storm will likely become a hurricane Wednesday over Hispaniola and then weaken.

Walls said it is too early to tell how the storm could affect the U.S. mainland.