MIAMI -- The National Hurricane Center in Miami says a tropical depression over the eastern Caribbean could reach tropical-storm strength before turning north in the next couple of days.

The tropical depression is the 15th of the season and would be named Omar if it strengthens as forecast.

Tropical storm watches have been issued for Puerto Rico, the U.S. Virgin Islands, the British Virgin Islands and parts of the Dominican Republic.

As of 8 p.m. EDT, the depression had top sustained winds near 35 mph. Its center was located about 355 miles southwest of San Juan, Puerto Rico, and it was nearly stationary.

Far out in the Atlantic, the remnants of what had been Tropical Storm Nana continued to weaken.

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