76ºF

Florence and the tropics as we may see two hurricanes make landfall next week

Florence is aiming at the Carolinas, TD 9 towards the lesser Antilles

Helene
Helene

JACKSONVILLE, Fla. – You can tell we are nearing the peak of the Atlantic hurricane season, as we head through the weekend The Weather Authority is monitoring four potential systems in the Atlantic.

The statistical peak is Sept. 10, meaning that is when we usually have the highest volume of numbered or named systems in the Atlantic Ocean. 

Long range forecast models hint that late next week we may see two hurricanes making landfall,  the first being what will be Tropical Depression 9 near the Lesser Antilles and Florence possibly along the Carolinas. Significant changes to both tracks are possible and even expected over the next few days. 

Florence

One factor that may dramatically change the track for Florence is the intensity of the storm. Stronger storms are taller, with vertical development higher into the atmosphere. Taller storms are more influenced and steered by upper-level winds, which tends to turn storms further North. Weaker storms trend more Westerly because they are not as tall and are less influenced. 

Over the weekend, we may see the projected track for Florence shift further West, since Florence has weakened into a Tropical Storm and will be less influenced by upper-level winds. Florence is expected to rapidly re-intensify into a major hurricane by Monday. The growth of Florence would mean it will be more likely to see it turn North.

If Florence does not re-intensify over the weekend we may see a westerly track, which could mean that we would see more of an effect from Florence. It is too so

photo

on to tell where Florence will eventually end up, but we should have a better idea by late Sunday, early Monday. 

One interesting factor in our favor is history. The National Hurricane Center's Florence forecast places the storm at 30N and 70W in 3 days, historically very rarely do hurricanes impact the United States from this location. More often, they end up recurving North into the Atlantic.

Developing systems

We are also monitoring a tropical storm named Helene and TD9 and one system that does not have a high likelihood to develop. First is Tropical Storm Helene, just off of the coastline of Africa. Satellite imagery and surface observations indicate that the area of low pressure that moved off the west coast of Africa has developed a closed circulation that appears to be well defined.

Helene
Helene

Environmental conditions of light to moderate easterly shear and warm sea surface temperatures should support development of this system, and the NHC forecast shows it becoming a Hurricane in the next 3-4 days.

Next is Tropical Depression 9 which is gradually becoming better organized, we are monitoring it a little over 650 miles West of the Cabo Verde islands and TD9 is gradually becoming more defined. With the showers and thunderstorms fairly concentrated near the center, further development is expected over the weekend.. 

TD9 soon to be Isaac
TD9 soon to be Isaac

And lastly, there is an area of showers northwest of Bermuda that does not have a high likelihood of development. The National Hurricane Center places a 10% chance on it to develop over the next 2 days and only a 20% chance to develop over the next 5 days. Little to no forward motion is anticipated. 

Florence and the tropics
Florence and the tropics

About the Authors: