3 Things To Know About Invest 99-L

The area of storminess known as Invest 99-L that we've been monitoring for days is moving towards the southeast Gulf of Mexico where it could develop further.

Below are three things to know about this system right now.

(FORECAST: The Latest on 99-L) 

1.) Rain From Invest 99-L Has Been and Will Continue to be Impactful

This system has dumped locally heavy from the Leeward Island to Hispaniola, the Bahamas and Cuba since last week.

In the Dominican Republic, the heavy rain displaced more than 1,700 people, according to the Dominican Today. Parts of eastern Cuba saw 3-5 inches of rain from the system on Saturday.

More locally heavy rain is expected from 99-L into Monday, mainly in Cuba and parts of extreme southern Florida. This could result in possible flooding for some areas.

Later this week, the system could bring heavy rain to the eastern Gulf Coast region no matter how strong it becomes.

(MORE: What is an Invest?)

2.) Why Has This System Not Developed So Far?

Since last week, Invest 99-L has been battling the two nemesis of tropical cyclones, dry air and wind shear.

Wind shear and dry air can slow or prevent the development of tropical systems.

Most recently, wind shear has been the biggest inhibitor to the development of this system.

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Wind shear around the system will continue through Sunday.

This wind shear and dry air could become less prevalent when the system reaches the Florida Straits and Gulf of Mexico early this week, possibly allowing it to develop.

3.) Will it Develop and Where Will it Track in the Gulf of Mexico?

There remains a large degree of uncertainty around how much this system will develop once it gets into the southeast Gulf of Mexico.

For now, the clockwise flow around upper-level high pressure over the eastern United States will steer 99-L west-northwest towards the Gulf. That high will weaken by Tuesday, allowing this system to move more north with time in the general direction of the eastern Gulf Coast.

The intensity of any system approaching the eastern Gulf Coast later this week remains extremely uncertain. It could range from an undeveloped low to a tropical storm or even a hurricane.

One impact that will most likely occur no matter whether this system develops or not is heavy rain. This heavy rain could fall on already saturated parts of the eastern Gulf region later this week. 

Any other impacts such as wind and surge will be dependent on the intensity of the low, which as we mentioned before, is highly uncertain.

For more details, see our full forecast article at the link below.

(FORECAST: Invest 99-L)

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