Subtropical Depression 17 formed over the western Atlantic Ocean early Wednesday, according to the National Hurricane Center.
It is not expected to be a threat to Florida or the United States. Heavy rainfall is possible for the northern Leeward Islands and Puerto Rico over the next day.
The system, which was about 270 miles north-northwest of San Juan, Puerto Rico, was expected to strengthen and possibly become a tropical or sub-tropical storm later Wednesday.
It would be called Otto.
The system had sustained winds of 35 mph and was moving northwest near 8 mph. It's expected to turn north-northwest by late tonight, tracking back out into the Atlantic.
Compared with tropical systems, the highest winds in subtropical systems are typically located further away from the center and there is less convection, said Bay News 9 meteorologist Juli Marquez.
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