The Atlantic Ocean forms new storm Jerry, but there is no immediate threat to land.
As of 11 a.m. EDT (1500 GMT), Jerry was located about 1,070 miles (1,722 kilometers) west of the Azores, with maximum sustained winds near 40 mph (64 kph).
Forecasters said the storm was nearly stationary but was expected to begin moving slowly north-northeast later Sunday.
Subtropical storms are hybrid systems that get energy from warm waters like tropical ones, but also from colliding warm and cold air masses like more common storms over land.
Jerry is the 10th named storm of the Atlantic hurricane season. Its winds extended outward about 105 miles (169 kilometers).
In the Pacific, Ivo was downgraded from a tropical storm to a depression early Sunday, the Hurricane Center said.
At 2 p.m. EDT (1800 GMT), the center of Ivo was about 95 miles (153 kilometers) southwest of the southern tip of Mexico's Baja California peninsula and moving east-northeast at 4 mph (6.4 kph).
The depression - which had maximum sustained winds of 30 mph (48 kph) - is expected to pass over or near the southern tip of Baja near the resort cities of Cabo San Lucas and San Jose del Cabo, a region that was hit early this month by Hurricane Henriette. Rainfall of 1 to 2 inches (2.5 to 5 centimeters) is forecast for the area.