08/13/2011 12:06 pm ET Updated Oct 13, 2011

Tropical Storm Franklin strengthens slightly

MIAMI (Reuters) - Tropical Storm Franklin strengthened slightly after forming northeast of Bermuda on Saturday, but it was moving over open seas and posed no threat to land, forecasters at the U.S. National Hurricane Center said.

The sixth named storm of the 2011 Atlantic hurricane season also posed no threat to oil and gas production installations in the U.S. Gulf of Mexico.

The storm had top sustained winds of 45 miles per hour at about 11 a.m. EDT. But it was forecast to begin weakening gradually on Saturday night before dissipating by Monday, the Miami-based hurricane center said.

Franklin was about 605 miles northeast of Bermuda and was moving east-northeast over the open Atlantic, away from the British island and away from the United States.

Forecasters were also keeping watch over several other tropical disturbances in the Atlantic as the June-through-November hurricane season moved into its traditionally most active period.

(Writing by Tom Brown)