Tropical Storm Imelda formed Sunday and is expected to become a hurricane on a forecast track that could take it away from the U.S. East Coast early this week.

The storm was causing disruption in the Bahamas and Cuba on Sunday, and a tropical storm watch was posted in parts of Florida.

Meanwhile, Hurricane Humberto weakened very slightly but remained a strong Category 4 storm in the Atlantic, threatening Bermuda.

On Sunday, the usually busy streets and seaside of New Providence Island were deserted but constant rain started to flood the streets.

Choppy sea water and a gusty wind kept tourists and residents away from the popular Potters Bay Dock in Nassau.

Flights to and from the islands have been cancelled, with airports expected to open after midnight if weather conditions improve.

Imelda was threatening parts of Cuba and the Bahamas with heavy rainfall and flash flooding, with portions of the Bahamas under a tropical storm warning.

The Bahamas’ Department of Meteorology said moderate to heavy rains would continue over the northwest and central islands, which include Nassau, Andros Island, San Salvador and Long Island.

Rainfall could reach between 6 inches (15 centimeters) and 12 inches (30 centimeters), with some isolated areas seeing up to 10 inches (25 centimeters).