NASSAU, Bahamas — A potential tropical storm is brewing in the Atlantic and by late Friday could threaten areas of the Bahamas recently devastated by Hurricane Dorian, forecasters warned.

The weather system remained a tropical depression but the National Hurricane Center said in a 5 p.m. update that a tropical storm warning was in effect for the Northwestern Bahamas, excluding Andros Island.

The center said the system was expected to become a tropical storm on Saturday “with gradual intensification thereafter.”

“Global models insist on further development, and the reliable guidance suggests that the cyclone could even reach hurricane intensity” in about three days, the center said. “By then, the system is expected to be over the Atlantic waters well southeast of the coast of the Carolinas.”