The system is expected to move north along the coast and eventually head out to see. But it could become a cyclone over the weekend.

An area of low pressure just east of the upper Florida Keys has a 70 percent chance of developing into a tropical cyclone over the next five days, but models disagree on what it means for Florida this weekend.

The system, which would be named Dorian if it gains tropical storm status, has a 40 percent chance of developing over the next 48 hours.

While heavy rain is expected from the would-be Dorian, National Weather Service meteorologists in Miami said Friday morning that “global weather models are all over the place and not in good agreement with how they handle this disturbance.”

Weak systems are notoriously hard to forecast and a nightmare for meteorologists when they are near land.

European models are deepening the disturbance as it nears Florida and then zipping it north along the coast. The U.S. model splits the disturbance into lower and upper level systems, with the low level moving west across Florida.

National Hurricane Center forecasters said the system is expected to move near or over Florida later today, which should limit development during the next day or so.

But conditions are more conducive for the organization later this weekend when forecasters said a tropical depression could form off Central Florida’s coast.

The next update from the National Hurricane Center is at 2 p.m.

“Regardless of whether this disturbance develops, the primary hazard for South Florida the next few days will be periods of heavy tropical rainfall with rounds of showers and thunderstorms through the weekend,” National Weather Service meteorologists warn. “Heavy rainfall may lead to some flooding in urban areas across the region.”

For Friday, rain in South Florida is expected to be driven by daytime heating and the sea breeze.

The Weather Prediction Center has put all of South Florida under a marginal risk for excessive rainfall today. More than 2 inches of rain is expected in Palm Beach County through Monday.

As of its 8 a.m. advisory, the hurricane center is also watching an area of showers and thunderstorms about 1,400 miles east-southeast of the Windward Islands. The has a 20 percent chance of development over five days.

It’s moving generally westward at about 15 mph and slow development is possible.

None of these systems pose a threat to Northwest Florida. Our forecast calls for a 50/50 chance of showers today and a 40 percent chance through the weekend, rising to 60 percent on Monday.