At that point, the National Hurricane Center will either declare it a tropical depression and give it a number (if its winds are less than 39 mph) or a tropical storm and give it a name (if its winds are between 39 and 74 mph).
Advertisement
The system has been dealing with wind shear and dry air over the past day, which has hampered its chances for development.
Tropical Storm Gaston is moving northwest at 15 miles per hour and is expected to become a hurricane by Saturday night or early Sunday.
As of Friday afternoon, Invest 99-L was a weak low-pressure system. First, I couldn’t understand why the GFS and then the Euro didn’t have much becoming of “99L” even once it entered the Gulf of Mexico where conditions appeared to be more favorable for development. Some models have scaled back the expected intensity of the wave and many have come together on a more west/northwest track, but there are still a lot of uncertainties ahead. It is still in an area that has some shearing that is not allowing the system to get stronger.
“The bottom line is that the extended forecast for this tropical wave still remains uncertain”, said Williams on Saturday.
I’ve struggled with two aspects of this forecast all along through the week.
Please remember that forecast errors at 4-5 days and beyond can still be quite high, so this is not an all clear. All interests in the central and northeast gulf should monitor the progress as we move into the late weekend.
Advertisement
A tropical disturbance must have a closed wind circulation in order to be named. I can promise you I will always discuss events like this in detail, with special attention paid to not over-hyping or unnecessarily scaring anyone. We will be tracking these systems for you.
