The British territory suspended ferry services on Tuesday as wind and rain started to pick up.
The National Hurricane Center in Miami says tropical storm conditions are expected late Tuesday, with up to 4 inches (10 centimeters) of rain predicted.
The storm was centered 165 miles (265 kilometers) south of Bermuda at midmorning and was moving north at 14 mph (22 kph) with maximum sustained winds of 40 mph (65 kph). Gabrielle is expected to strengthen in the next two days and pass over or near Bermuda by Wednesday morning.
Farther east over the Atlantic, Tropical Storm Humberto's maximum sustained winds have increased to near 65 mph (100 kph) and the storm is expected to become a hurricane.
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