A tropical storm and a tropical depression remained in the Atlantic Monday as a third system had a possibility of developing later in the week.
The seventh tropical storm of the season, Gaston, developed far over the Atlantic Monday, according to the National Hurricane Center.
The storm's maximum sustained winds had increased early Tuesday to near 50 mph. The U.S. National Hurricane Center says additional strengthening is forecast and Gaston is expected to become a hurricane by Wednesday.
Gaston is centered about 545 miles west of the southernmost Cabo Verde Islands and is moving west-northwest near 20 mph.
Elsewhere in the Atlantic, Fiona is barely maintaining its status as a tropical depression. Fiona's maximum sustained winds are near 35 mph.
The depression, which is expected to become a remnant low in the next few days, is centered about 455 miles south of Bermuda and is moving west-northwest near 13 mph.
A third system, a tropical wave, was about 550 miles east of the Lesser Antilles Monday. The National Hurricane Center gives the system a 60 percent chance of formation over the next five days as it is expected to move near Hispaniola and the southeastern and central Bahamas.