Forecasters said Tropical Storm Peter formed over the Atlantic Ocean early Sunday, and a new tropical depression was spinning over the far eastern Atlantic.
Peter was centered about 630 miles (1,015 kilometers) east of the northern Leeward Islands, the U.S. National Hurricane Center in Miami said in a 5 a.m. EDT advisory.
The tropical storm was expected to bring rain to the islands including the Virgin Islands and Puerto Rico through Tuesday. Forecasters expected 1 to 2 inches (3 to 5 centimeters) of rainfall through Tuesday.
Top winds were around 40 mph (65 kph) and Peter was moving northwest at 15 mph (24 kph). No coastal watches or warnings were in effect.
Get South Florida local news, weather forecasts and entertainment stories to your inbox. Sign up for NBC South Florida newsletters.
Only two other Atlantic hurricane seasons have had 16 named storms by Sept. 19 since the satellite era began in 1966. Those were the 2005 and 2020 seasons, according to Colorado State University hurricane researcher Phil Klotzbach.
Meanwhile, tropical depression Seventeen formed Sunday. Forecasters said it was over the far eastern tropical Atlantic Ocean, about 330 miles (530 kilometers) southwest of the southernmost Cabo Verde Islands.
The tropical depression had maximum sustained winds around 35 mph (55 kph). The system was expected to become a tropical storm later Sunday or on Monday, however there were no immediate threats to land, forecasters said.