Tropical Storm Karen strengthened early Tuesday from the twelfth tropical depression of the season in the open Atlantic Ocean but posed no immediate threat to land.

At 5 a.m. EDT, Karen was centered about 1,565 miles east of the Windward Islands, with top sustained winds near 40 mph, the National Hurricane Center said. It was moving toward the west-northwest near 16 mph and was expected to strengthen over the next 24 hours.

Tropical storm force winds extend outward up to 45 miles from Karen's center. On its current course, it is expected to hit two troughs, though forecasters are unsure how they will affect Karen.

Meanwhile, Tropical Storm Jerry weakened into a depression then dissipated in cooler waters. Jerry, which formed Sunday, broke up Monday night. Forecasters expected it to be absorbed by a larger non-tropical low pressure system on Tuesday.