Tropical cyclone formation is becoming increasingly likely this weekend east of the Lesser Antilles.
The “seed” is a tropical wave currently located to the southwest of the Cabo Verde Islands.
Immediate development not expected
A dry saharan air layer (SAL), wind shear and the broad nature of this system will prevent immediate development. However, by this weekend, wind shear should gradually decrease, allowing for development.
Model guidance
There is a consensus among the ECMWF, GFS and UKMET for a tropical depression to form by Sunday.
Support from the ECMWF ensembles (see figure 2) and GFS ensembles is also strong, with the former indicating a 70 to 80 percent chance of a tropical depression forming this weekend.
Latest from the National Hurricane Center
Here is the latest from the National Hurricane Center (NHC):
“A broad area of shower and thunderstorm activity is associated with a tropical wave located several hundred miles southwest of the Cabo Verde Islands. Little to no development of the wave is expected for the next few days while it moves westward across the eastern and central tropical Atlantic Ocean at about 15 mph. Environmental conditions are forecast to become more conducive for development over the weekend and a tropical depression could form by early next week several hundred miles east of the Lesser Antilles.”
They are going with a 60 percent chance of development over the next 5 days as of their 2 PM EDT Tropical Weather Outlook (see figure 1).
That is up from 40 percent last night and 50 percent this morning.
Lesser, Greater Antilles should monitor
The Lesser Antilles, Puerto Rico and Hispaniola should monitor the progress of this disturbance closely. If a tropical cyclone does form, impacts would be possible early next week.
Mainland U.S. should keep an eye on this system too
At this time, there is no reason to believe that this system will make landfall in the mainland United States (CONUS).
Ensemble guidance is currently indicting that a trough of low pressure will be in place to steer any storm moving into the southwest Atlantic/Bahamas next week out to sea (see figure 3).
Although, being so far out in time, a track out to sea is not set in stone.
With a track out to sea not a guarantee, the Southeast U.S. and Bahamas should keep an eye on soon-to-be Invest 96L.
