HOUSTON (KIAH) — A tropical wave, known as ‘Invest 98L’, continues westward through the Caribbean Sea with a very high likelihood of organization in the next few days. That means it could soon be labeled a tropical depression, or tropical storm Hermine.

Invest 98L is currently in the East Caribbean Sea, and heading west with a high chance of development

The National Hurricane Center says this tropical wave is currently encountering some wind shear, interfering with its ability to organize. But, conditions in the next few days become more favorable for organization. As of Thursday morning, it has a 70% chance of formation in the next two days, and a 90% chance in the next five days.

Invest 98L forecast tracks

Factors that influence when to expect an accurate forecast:

  • Reliable data: Hurricane reconnaissance aircraft have begun flying through Invest 98L. The first mission started Wednesday night. A second mission is occurring Thursday morning, with many more to come. These missions are crucial because weather instruments are dropped into the storm, giving computer models the data they need to more accurately forecast the storm. The aircraft is also able to pinpoint the center of circulation, which gives computer models a clear initial position.
  • Organization: It’s difficult to forecast a storm when it hasn’t fully formed yet. That’s the case right now. However, by this weekend it will likely be more organized, which makes it easier to forecast.
  • Increasing margin of error over time: Naturally, the farther into the future you’re predicting, the higher the margin of error becomes. Aside from the tropical system, computer models are attempting to predict what the surrounding atmospheric conditions will be several days in the future. Beyond five or six days, big forecast fluctuations are common.

So, when will we get a good idea of what this storm is going to do?!

I expect a clearer picture this weekend, and obviously the forecast will continue to get refined in the days to follow. As far as the U.S. is concerned, that should still leave a good amount of time for preparations because this system will likely be in the Northwest Caribbean on Monday, and then possibly pushing into the Gulf after that.

Chief meteorologist Adam Krueger