Peak of the 2022 Atlantic Hurricane Season?
2022 Atlantic Hurricane Season Update
by Aidan Cera
09/21/2022
Figure 1. National Hurricane Center 2-Day Graphical Weather outlook for 09/21/22 2PM EST.
The peak of the 2022 Atlantic hurricane season has arrived, albeit a little later than usual or expected. The NHC is currently watching 5 areas of concern, Major Hurricane Fiona, Tropical Storm Gaston, Invest 98L, Invest 99L and another tropical wave about to exit the coast of Africa. We'll look at each at system one by one below.
Major Hurricane Fiona (07L)
Fiona continues to track away from the Turks and Caicos and is holding intensity as powerful category 4 hurricane with 130 mph sustained winds and a central pressure of 937 millibars. The convective structure has begun to degrade with the eye beginning to cloud up and convection beginning to wain. The most likely reason for this is an eye wall replacement cycle. Given this possibility, it may be a while before we see a pronounced eye return, and intensity will likely begin to drop off and weaken. I certainly would not be surprised if Fiona weakens to a cat 3 or cat 2 again before the eye wall replacement cycle is complete.
Fiona is tracking generally northward and is expected to begin a northeast turn over the next day or so. The storm will then begin to accelerate northeast toward Bermuda due to increasing upper level flow due to a trough advecting southeast off the United States coast. Hurricane watches have been put into affect for the island of Bermuda along with tropical storm warnings. Fiona is expected to pass just northwest of Bermuda late Thursday through Friday as a major hurricane with 115mph winds or higher.
Fiona will then rapidly accelerate northeastward and begin to approach Nova Scotia as a low end major hurricane Friday night. On Saturday, Fiona will likely finish extratropical transition but remain a very powerful system with hurricane force winds impacting Nova Scotia and Newfoundland, Canada.
This has the possibility to be a historic event given the projected strength of Fiona once it arrives in Nova Scotia on Saturday. The wind field will also be quite extension given the extratropical nature so this will be a storm interests in Canada need to monitor closely as well as Bermuda more short term.
Tropical Storm Gaston
Tropical Storm Gaston is maintaining strength as a strong tropical storm in the north central Atlantic as it tracks northeastward today. Convection is not as organized as it was yesterday, but surface winds are holding steady at 65 mph and a central pressure of 1000 millibars. Gaston is expected to continue tracking east northeastward over the next 2 days then stall out before turning westward while becoming a post-tropical cyclone. Dry air will likely cause Gaston to gradually weaken after tomorrow and the system is expected to become post tropical by Saturday. Gaston may bring small impacts to the Azores as it stalls out just to the north northwest. Again though, dry air will likely be weakening Gaston and robbing it of convective potential.
Invest 98L
Invest 98L is the most pressing matter in the tropics right now. There has been clear consistency across most of if not all the models that this system may impact the western Caribbean Sea, and Gulf Coast of the United States sometime next week.
Looking at 98L currently, convection is relatively limited as well as surface vorticity due to northerly shear thanks to Fiona's outflow. While impeding the system now, this shear will relax in about 2 days as Fiona lifts out leaving behind a more anticyclonic pattern aloft with weaker surface trades due to a initial lack of high pressure north of the Caribbean Sea. 98L will be steered westward through the Caribbean Sea by the weaker trades into a highly favorable kinematic and thermodynamic environment. Given this, once 98L forms into a tropical cyclone, which will likely take several days due to Fiona's outflow, it will most likely be all systems go for rapid intensification.
The location of where 98L goes remains to be resolved. Models are wind shield wiping between taking it over the Yucatan Peninsula to tracking over central Cuba. This is not something we will be be able to nail down until 98L has developed a well defined core and we are able to observe just how strong the system is when it tracks further into the Caribbean Sea. The stronger the system, the sooner it will likely turn north and the weaker it is the longer it will likely take to turn north depending on ridging and trouging patterns next week. The National Hurricane Center is giving this area a 90% chance of developing in the next 5 days.
Invest 99L
Invest 99L sort of snuck up on us in the central Atlantic. A tropical wave with a decent low level vorticity signature and convective plum has been persisting since yesterday. There does appear to be a closed surface low based on satellite but it is rather elongated and convection is not organized enough yet for designation of a tropical cyclone.
Proximity to dry air will hinder 99L from doing much in the coming days but other environmental conditions may allow for a weak and brief tropical cyclone to develop in this area by the end of the week. The National Hurricane Center is giving this area a 30% chance of developing in the next 5 days.
AOI Over west Africa
A vigorous tropical wave is about to track off the coast of Africa later tonight or tomorrow. A closed surface low already appears present on satellite and both the GFS and ECMWF models show rapid development as soon as the wave exits the coast. This wave will be tracking in to a region of very light steering flow so will likely track northward east of the Cabo Verde Islands. Sea surfaced temperatures will be favorable in the short term with a moisture plum associated with the tropical wave leading to at least a marginally favorable environment for the development of a tropical cyclone. The National Hurricane Center is giving this area a 50% chance of developing in the next 5 days.
For more information on these areas of concern, please visit
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