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Harvey will bring rain and gusty winds to the Windward Islands.

Then, it will track across the Caribbean Sea into next week.

Harvey is not a threat to the United States.

Two other areas of disturbed weather are being monitored for development in the Atlantic Basin.

Tropical Storm Harvey is beginning to bring rain to theWindward Islands, and may posea threat early next week in parts of Central America's Caribbean coast.

Tropical storm warnings have been issued for parts of the Windward Islands, including Martinique, St. Lucia, Barbadosand St. Vincent and the Grenadines. Warnings are issued when tropical storm conditions are expected within 36 hours. A tropical storm watch is in effect for Dominica, where those conditions are possible within that timeframe.

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Tropical storm conditions, with winds of 39 mph or greater, are expected to first reach the Lesser Antilles within the warning areaearly Friday, making outside preparations difficult or dangerous. Tropical storm conditions are possible in the watch area on Friday.

Thunderstorm activity over the storm has not changed much since a Thursday afternoon hurricane hunter flight found winds of 40 mph. Another mission is scheduled into Harvey on Friday morning to see if anything has changed in the storm.

Harvey will bring2 to 4 inches of rain across the Windward Islands from Martinique southward to Grenada, which could trigger life-threatening flash flooding and mudslides in mountainous terrain.

After that, the system will then track westward through the rest of the Caribbean Sea, and will likelypose a threat to parts of Central America and/or Mexico's Yucatan Peninsula early next week.

It's not clear how strong thistropical storm will become through its Caribbean trek, due to potential interaction with dry conditions and sinking air. Interests throughout the Caribbean should monitor the progress of Harvey through early next week.

At this time, Tropical Storm Harvey is not a threat to the United States.

Invest 92L continues tofesterafew hundred miles to the east of Harvey.

This invest has shown signs of strengthening through late day Thursday, and could become a tropical depression on Friday or over the weekend.

A fresh surge of such dry air, known as theSaharan Air Layer (SAL),is pushing toward 92L right now.This dry air may mix in with the disturbance, preventing thunderstorms from persisting and clustering.

Furthermore, if 92L tracks farther north, as expected, wind shear the change in wind direction with height is strongerto the north of the Leeward Islands, according to an analysis from the University of Wisconsin.

This hostile wind shearthat typically rips apart tropical disturbances and weaker tropical cyclones may inhibit 92L from developing significantly, if it gains enough latitude north of the Leeward Islands this weekend.

A hurricane hunter mission has beententatively scheduled for Saturday afternoonto determine if Invest 92L has organized and strengthened enough to be classified as atropical depression or tropical storm.

It's worth noting that even if 92L doesn't develop into a tropical cyclone the next few days, this disturbance will likely continue migrating through the Bahamas, then into the Gulf of Mexico next week and will be monitored for any potential later development.

Finally,a tropical wave emerged off the west African coast Wednesday, well east of Harvey and 92L, kicking offits journey across the eastern Atlantic Ocean.

This latest wave may develop by the weekendbut won't near the longitude of the Lesser Antilles until early next week.

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What form that system takes tropical wave, depression, storm or hurricane and where it exactly tracks remain unknown at this time, though the majority of forecast guidance suggests this system will track north of the Leeward Islands.

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We are in the climatological peak of the hurricane season, so each tropical wave or area of low pressure in the Atlantic Basin must be watched closely for development. As the image to the right shows, named storms can form in about every part of the Atlantic Basin this time of year.

As an example, thedisturbance that formed into Gertto thenortheast of the Bahamas lastweekend was tracked for nearly 10 days before it finally developed. That tropical wave also originated over Africa.

That said, not all tropical waves orlow-pressure systems that emerge from Africa become tropical depressions or tropical storms, but they are all monitored closely, particularly when atmospheric conditions are ripe for them to spin up.

(MORE: Where Every U.S. Landfalling Hurricane Began Its Journey)

Now is a good time to make sure you have a plan in case of a hurricane strike. The Federal Alliance for Safe Homes has an excellent website to help you make your plan.

Check back with weather.com for updates in the days ahead on these latest systems and the rest of hurricane season.

(MORE: NOAA Predicts Active Rest of the Hurricane Season)

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Tropical Storm Harvey Begins to Drench the Windward Islands; Tropical Storm Conditions Expected to Arrive Early Friday - The Weather Channel