Skip Navigation Links
NOAA NOAA United States Department of Commerce

Tropical Depression NINE


Tropical Depression Nine Discussion Number   2
NWS National Hurricane Center Miami FL       AL092018
1100 PM AST Fri Sep 07 2018

The depression continues to be impeded by moderate easterly shear
with the center of circulation decoupled to the east of a deep
convective banding feature.  The initial intensity is held at 30 kt
based on subjective intensity estimates from TAFB and SAB.

The dynamical-statistical intensity guidance, as well as the
large-scale models, indicate that the shear should diminish to less
than 10 kt within the next 24 hours.  A more favorable upper-wind
pattern along with warm oceanic temperatures is expected to promote
steady strengthening commencing after that time.  The intensity
forecast is based on a blend of the IVCN and the HCCA consensus
models and remains below the stronger HWRF at days 4 and 5.

The depression has been meandering during the past several
hours, as a result of weak low- to mid-level steering currents
created by a deep-layer trough digging southward over the eastern
Atlantic.  In 12 to 24 hours, a westward motion with a gradual
increase in forward speed is forecast thereafter as the trough lifts
northeast, and the subtropical ridge re-establishes to the north of
the cyclone.  The NHC track forecast lies closest to the HCCA and
TVCN guidance and takes the system toward the Lesser Antilles by the
end of the forecast period.


INIT  08/0300Z 13.9N  34.9W   30 KT  35 MPH
 12H  08/1200Z 14.1N  35.6W   35 KT  40 MPH
 24H  09/0000Z 14.2N  36.7W   35 KT  40 MPH
 36H  09/1200Z 14.3N  38.4W   45 KT  50 MPH
 48H  10/0000Z 14.4N  40.4W   55 KT  65 MPH
 72H  11/0000Z 14.4N  45.2W   75 KT  85 MPH
 96H  12/0000Z 14.4N  50.2W   80 KT  90 MPH
120H  13/0000Z 14.9N  56.2W   85 KT 100 MPH

Forecaster Roberts