Tropical storm warning may be needed for Cayman-NHC

Regardless of whether it becomes a tropical cyclone, one thing is certain: The disturbance will bring heavy rain to Cuba and Florida this weekend, then to the Northeast on Sunday as it interacts and merges with a strong mid-latitude storm.

A tropical depression or storm is likely to form late Friday night into early Saturday as the system moves northward over the northwestern Caribbean Sea.

The government of Cuba has issued a Tropical Storm Warning for the Cuban provinces of Isla de la Juventud, La Habana, Ciudad de la Habana, Matanzas, Cienfuegos, and Villa Clara.

The National Hurricane Center has upgraded the probability of development to 80 percent, as a tropical system moves north off the northeastern coast of Nicaragua.

Heaviest rains will be in south Florida. More information is expected to be released by the Cayman Islands National Weather Service around 4:30 p.m.

"Shower and thunderstorm activity has increased and become more concentrated in association with a trough of low pressure over the northwestern Caribbean Sea", read Friday's National Hurricane Center outlook. It's just rain for us with a breeze or two.

The system has a 40 percent chance of developing into at least a tropical depression within five days. By Saturday, the system could bring heavy rain across parts of south Florida and the Florida Keys.

Residents of the Cayman Islands, central and western Cuba and Jamaica are advised to expect locally heavy rainfall.

It is expected to develop into a tropical storm tonight or Saturday.

Friday afternoon, a Hurricane Hunter plane probing the weather system discovered winds near 40 miles per hour but no defined center.