Alexandra Cranford / WWL Eyewitness News Forecast Team

A weekly discussion of the tropics from the Eyewitness News Forecast Team

We've added another name to our list of storms this hurricane season. Subtropical Storm Melissa has formed in the central Atlantic Ocean.

The first thing you might notice about Melissa is the title... what makes this storm subtropical instead of tropical?

The main difference is the structure of the storm. A subtropical storm has a larger center with mostly clear skies. The heavy thunderstorms are farther removed from the center at a distance of about 100 miles. You can see this looser structure in this satellite shot of Melissa.

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Also, a subtropical storm can have cold or warm fronts associated with it, while a tropical storm does not.

And the formation process is different for subtropical storms. They form with cold air at the core. The cold core eventually heats up over warm ocean waters.

Finally, subtropical storms can pack strong winds just like tropical storms, but the rain threat is lower. A subtropical storm can become a fully tropical storm or hurricane if warm water becomes its only source of energy.

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Ok, now that we know about subtropical storms, let's return to Melissa. The good news is Melissa is no threat to land. A cold front rolling off the East Coast will shove the system north/northeast. It'll stay on that track for the remainder of its lifetime.

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As for its intensity, Melissa could strengthen a bit before it weakens over northern ocean waters. Right now it looks like it will remain a subtropical system until it fades to a remnant low on Wednesday or Thursday.

Melissa makes the thirteenth named storm this season. That's one more than the average number of named storms. And of course, Melissa is quite a latecomer. It formed with less than two weeks left in this hurricane season.

Check back next week for your final Talkin' Tropics discussion. We'll wrap up our series with a look back at highlights of the 2013 season.

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