99L is now moving northwest and might gather strength as upper-level winds become more favorable for its development over the weekend.
That said, environmental conditions are expected to be good enough to allow Eight to become a tropical storm on Sunday, and it should strengthen as it moves northward in the western Atlantic.
The National Hurricane Center said Tropical Depression Eight would not threaten the US and stay to the east.
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She said that all the lights on the ship, which would have signaled its presence in the water, were either dimmed or turned off. The blackout happened while the vessel crossed through the Indian Ocean, Arabian Sea, the Gulf of Aden and the Suez Canal.
The storm is expected to continue to track to the north-northwest today - and toward the U.S. East Coast.
A turn toward the north is forecast to occur Sunday night, followed by a turn to the north-northeast on Monday. It is now moving to the west-northwest at around 10 to 15 miles per hour and is expected to meet up with a larger area of low pressure southwest of the Cabo Verde Islands in the next few days. The NHC advises that it is still capable of dropping heavy rains on Florida over the next few days, though, even if it doesn't organize.
Previously dubbed Invest 99L, this system has become a little better defined and the shower and thunderstorm activity has increased, allowing the upgrade to Tropical Depression Eight.