Since 2012 on the now retired Weather Underground blogs, I have been posting annotated "birdseye view" charts of the Atlantic basin, with a detailed explanation and forecasting that references the chart. From there you may know me as "NCHurricane2009." While I now do these "birdseye view" posts here, I will continue to do comments at Yale Climate Connections via Disqus where the former Weather Underground community has moved to. Feel free to reply to me there, at my Disqus feed at this link, or via e-mail at 

  • NCHurricane2009


*******Note that forecast and outlooks in this post are NOT the official forecast from the National Hurricane Center (NHC). They are my own detailed views on the Atlantic tropics based on current observations and latest computer model runs. As such do not make decisions based on my posts...consult news and warnings from your local weather office...and any evacuation orders issued by local governments to make the most informed and best decisions. Visit the NHC website (hurricanes dot gov) for the latest watches/warnings and official forecasts on active tropical cyclones.**********

...MONDAY SEPTEMBER 26 2022 10:30 AM EDT...

The following is a special update on the tropical low pressure area that has been meandering in the eastern tropical Atlantic... designated as area of interest #33 on the home page of this site... which has become better organized and will likely become a tropical cyclone either by 11 AM EDT or later today. Meanwhile Tropical Storm Ian in the western Caribbean Sea is now Hurricane Ian... and is a threat to the Cayman Islands... western Cuba... the Florida Keys... and west coast of the Florida peninsula while expected to intensify further. See full update #112 available on the home page of this site for more information on Ian and the rest of the Atlantic tropics.

AREA OF INTEREST #33...Visible satellite image of the organizing tropical low pressure in the eastern Atlantic (image taken at 1340Z):

The wandering tropical low pressure spin in the eastern Atlantic has maintained persistent thunderstorm activity... and overnight the surface swirl has drifted northward underneath the activity. As a result... this system is better organized as the thunderstorm activity is well-organized and staying aligned with the surface center. A tropical cyclone appears to be forming... and I have begun a track and intensity forecast for this system as outlined below.

Expecting this system to remain generally stationary over the next 36 hours as it is located in a saddle point of conflicting steering between the broad low pressure area to the northeast and Atlantic surface ridge that for days has been trying to push this system west. Afterwards... the large-scale cold core upper trough in the region which has been inducing said broad low pressure area will weaken while remaining isolated from cold air thanks to the ongoing warm core north Atlantic upper ridge. The upper ridge will also break the weakening trough into a series of upper vortices that retrograde southwestward around the ridge. As the cold core upper trough and associated surface low pressure area to the northeast weakens... the Atlantic surface ridge will finally try to push this system west. However an increasing north angle is depicted in the developing west track as the surface ridge will itself develop a weakness to the northwest as the current frontal system over the eastern US will have moved offshore. And as this system likely becomes a stronger/taller tropical cyclone... the upper southwesterly flow ahead of one of the decaying upper vortices would also coax this system on a more northward track. The upper southwesterly flow is expected to become a detriment to this system in the long range by shearing it. Regarding intensity... the dry Saharan air that was northeast of this system has faded away in the latest true-color visible satellite pictures... and this system remains parked below warm waters and low shear beneath a tropical upper ridge axis in the region. Therefore I project this system becoming a hurricane in the next 48 hours... but do not project an intensity higher than category 1 as it moves toward the aforementioned upper southwesterly shearing winds. The shear explains why I do not strengthen this system in the 48 to 72 hour window... followed by weakening beyond 72 hours. This system is expected to stay well-away from land areas during its life cycle.

****** forecast. Visit (hurricanes dot gov) for official forecast***********

0 Hr Position (1200Z Sep 26)...Tropical low centered at 14.8N-35.5W

IOH 24 Hr Forecast (1200Z Sep 27)...60 mph maximum sustained wind tropical storm centered at 15N-35.5W

IOH 48 Hr Forecast (1200Z Sep 28)...85 mph maximum sustained wind hurricane centered at 15.5N-36.5W

IOH 72 Hr Forecast (1200Z Sep 29)...85 mph maximum sustained wind hurricane centered at 17N-39W

IOH 96 Hr Forecast (1200Z Sep 30)...65 mph maximum sustained wind tropical storm centered at 20.5N-42.5W

IOH 120 Hr Forecast (1200Z Oct 1)...35 mph maximum sustained wind tropical depression centered at 23N-46W

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