Tropical Depression Seven Discussion Number   4
NWS National Hurricane Center Miami FL       AL072024
500 AM AST Thu Sep 12 2024

The system has changed little in organization overnight, with 
limited deep convection and slight banding features.  An 
AMSR-2 microwave image suggested that the circulation was still 
somewhat broad since the cloud bands were not very tightly curved.  
Subjective Dvorak classifications from TAFB and SAB were T2.5/35 kt 
and T2.0/30 kt, respectively.  The advisory intensity is held at 30 
kt given the depression's lack of increased organization.  This is 
also in agreement with a DMINT objective intensity estimate from 
UW-CIMSS based on the AMSR data.

The cyclone continues on a west-northwestward heading with an 
estimated motion of 290/15 kt.  A gradually weakening ridge over the 
eastern subtropical Atlantic should maintain this general motion 
with decreasing forward speed over the next 2-3 days.  Later in the 
forecast period, an amplifying trough is expected to erode the 
ridge, which should cause the cyclone to turn at least a little to 
the right.  The track guidance becomes somewhat divergent in the 4- 
to 5-day time frame, but is in overall agreement on a rather slow 
motion.  The official track forecast is similar to the previous NHC 
prediction and close to the various dynamical model consensus 
solutions.

Environmental conditions seem fairly conducive for at least gradual 
strengthening during the next few days, with low- to 
moderate-vertical wind shear and marginally warm SSTs.  However, the 
models are not very bullish on strengthening until near the end of 
the forecast period.  This may be due to a somewhat stable air mass 
over the eastern Atlantic.  The official intensity forecast is 
similar to the Decay-SHIPS model guidance through 72 hours, but 
shows no change after that time given the uncertainties in intensity 
prediction. 


FORECAST POSITIONS AND MAX WINDS

INIT  12/0900Z 17.3N  33.0W   30 KT  35 MPH
12H  12/1800Z 18.1N  34.9W   35 KT  40 MPH
24H  13/0600Z 18.9N  37.4W   35 KT  40 MPH
36H  13/1800Z 19.4N  39.3W   40 KT  45 MPH
48H  14/0600Z 19.7N  41.0W   45 KT  50 MPH
60H  14/1800Z 19.9N  42.3W   45 KT  50 MPH
72H  15/0600Z 20.0N  43.6W   45 KT  50 MPH
96H  16/0600Z 20.7N  45.6W   45 KT  50 MPH
120H  17/0600Z 21.2N  47.1W   45 KT  50 MPH

$$
Forecaster Pasch