Tropical storm warnings extend from the Lesser Antilles to parts of the Bahamas, including Puerto Rico, as Tropical Storm Isaias (ees-ah-EE-ahs) moves into the Greater Antilles and could affect Florida this weekend and parts of the eastern U.S. early next week.

The disturbance formerly known as Potential Tropical Cyclone Nine developed a closed circulation south-southwest of Puerto Rico, Wednesday night, allowing the National Hurricane Center to reclassify the system as a tropical storm.

(MORE: Hurricane Season Terms You Need to Know)

The latest watches and warnings are shown in the map below, from the Leeward Islands to the central Bahamas. A warning means tropical storm conditions are expected in the next 36 hours. A watch means tropical storm conditions are possible within 48 hours.

Watches and Warnings

Bands of heavy rain and squalls continue to rotate through the northern Leeward Islands, Virgin Islands and Puerto Rico and are beginning to arrive in the Dominican Republic. At times, these bands are producing wind gusts above 40 mph.

One squall produced a 52 mph gust as it swept through St. Thomas in the U.S. Virgin Islands late Wednesday morning. A wind gust to 51 mph was clocked at San Juan, Puerto Rico, Wednesday afternoon.

Current Radar, Satellite, Watches and Warnings

Below is a look at what we know about the forecast for any potential U.S. and Caribbean impacts.

The NHC projected path below shows that this system could be located near or on either side of the Florida Peninsula by this weekend, then gradually northeastward. However, this forecast is not nearly as straightforward as it might seem.

Current Information and Projected Path

There are a number of reasons for this uncertainty.

First, this system is in a formative state, with transient centers of circulation that may hop around over the next day or so.

Eventually, one cluster of thunderstorms may begin to take over in this large storm. Where exactly that occurs is uncertain, and could cause a shift to the position, and, hence, the forecast path of this system.

This system also has multiple obstacles to combat with the next few days that are important for its potential mainland U.S. future.

One of those obstacles could be a track of this system over the mountainous terrain of Hispaniola - Dominican Republic and Haiti - long known as a hurricane shredder with mountains up to 10,000 feet elevation.

The mountainous terrain of Hispaniola can significantly impact tropical cyclones and disturbances.

Hispaniola could either be a speed bump or completely shred the system as it passes through Thursday.

But there's an alternative scenario in which the main area of low pressure could finally form north of Hispaniola, avoiding the "shredding scenario" over land.

This system may also have to battle unfavorable upper-level winds - producing what meteorologists refer to as wind shear - along its Caribbean and Bahamas track. This is a nemesis of tropical cyclones.

Current Satellite, Wind Shear Analysis

The bottom line is that it's too early to precisely determine this system's future track and intensity, especially with regard to the mainland U.S.

It's even possible the system could be ripped apart, or at least weakened by any of the aforementioned obstacles before it ever nears Florida.

As it stands now, the system, in whatever form, is expected to arrive in eastern Florida Saturday, and possibly central or northern Florida Saturday night into Sunday.

However, the possible outcomes with regard to the mainland U.S. ranges from a track into the eastern Gulf of Mexico to a track over at least parts of the U.S. East Coast to a near-miss of the Eastern Seaboard.

This is due to the steering features in the atmosphere - the Bermuda high and an upper-level dip in the wind flow over the Mississippi Valley - as well as the strength of the system.

In general...

-Farther west track: If the system is weaker and/or the Bermuda high is stronger and extends farther west.

-Farther east track: If the system is a bit stronger and/or the Bermuda high is not as strong and farther east.

Steering Factors in Play

Furthermore, if wind shear isn't too hostile and the system avoids as much land as possible, warm water is plentiful, and could allow the system to intensify more than expected.

Residents along the Southeast and Gulf Coasts should monitor the progress of this system closely and have their plans ready to go, in case they're needed.

This system is producing strong wind gusts and bands of heavy rain over the U.S. territories.

Current Wind Field

Conditions in the northern Leeward Islands should improve Thursday.

Heavy rain and gusty winds in Puerto Rico and the Virgin Islands will last into Thursday morning before conditions improve.

For the Dominican Republic and Haiti, their worst conditions with the system will occur from Thursday morning through Thursday night.

Conditions will begin to deteriorate in the southeast Bahamas and Turks and Caicos Thursday afternoon, with rain and squalls possible into Friday.

While some rain is needed to help the long-term drought in eastern and southern Puerto Rico and the Virgin Islands, locally heavy rainbands will likely trigger dangerous flash flooding and mudslides, particularly in higher terrain.

Hispaniola's mountainous terrain will also make it very prone to flooding and mudslides. Locally up to 8 inches could fall in some areas through Thursday.

Rainfall Forecast

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Disturbance in the Caribbean Becomes Tropical Storm Isaias; Could Have Impacts to Florida This Weekend - The Weather Channel