New tropical depression likely to become major hurricane; 'needs to be watched'

TAMPA, Fla. - While Peter and Rose have been downgraded to a tropical depression – and forecasters have continuously said those storms pose no threat to the U.S. – the season's newly formed 18th tropical depression may be worth keeping an eye on.

"We’ve got two tropical depressions, Rose and Peter, falling apart. We weren’t concerned about them anyway, so that’s good. In the meantime, you’ve got this little spin out here, this is the one that needs to be watched," says FOX 13’s meteorologist Dave Osterberg. 

LINK: Track the tropics on MyFOXHurricane.com

Wednesday evening, the National Hurricane Center said the tropical wave several hundred miles southwest of the Cabo Verde Islands had closed circulation and strengthened into Tropical Depression 18. 

The system is moving west at 15 mph with winds of 35 mph. Forecasters expect it to become Tropical Storm Sam before long, and they say it will likely grow into a major hurricane early next week as it continues west.

Long-range computer models offer two different forecast paths – one curving north and another keeping it in the Caribbean.

"There are two schools of thought were these computer models, way to the north and right or a lot closer to these islands," Osterberg said. "This one does bear watching but it very, very far out still."