Tropical Storm Helene is expected to rapidly intensify and grow larger over the eastern Gulf of Mexico before whipping Florida with damaging winds and torrential downpours, according to the National Hurricane Center in Miami.

Helene is expected to rapidly intensify into a major and massive hurricane with 115-mph winds by the time it makes landfall Thursday.

It is forecast to become Tropical Storm, and then Hurricane Helene during the next 24 hours.Threat level: The storm, which has been slow to organize over the far western Caribbean, is expected to rapidly intensify once it develops an well-defined center of circulation and moves into the southeastern Gulf of Mexico.