Official Discussion issued by the National Hurricane Center

Gordon (AL072024) DATA RELEASED: 9/16/2024 9:00:00 PM UTC

Copy of official data

Tropical Depression Gordon Discussion Number  22
NWS National Hurricane Center Miami FL       AL072024
500 PM AST Mon Sep 16 2024

Gordon is producing only a few sporadic bursts of deep convection, 
mainly over the southern and eastern portion of its circulation.  
The vertical wind shear does not appear to be very strong at this 
time, as evidenced by the relatively slow motions of the cirrus 
clouds over the system.  Since the cyclone is situated over a 
warm ocean, the suppression of convection is probably due to a 
stable air mass and/or dry air.  The advisory intensity is held at 
30 kt in accordance with an objective estimate of 32 kt from 
UW-CIMSS and a subjective Dvorak Current Intensity number of 30 kt 
from TAFB.

Gordon continues to move slowly westward with a current motion 
estimate of 270/5 kt.  A high pressure area that was north of the 
system over the past couple of days is shifting westward, and being 
replaced by a mid-level trough within the next day or two.  Also, 
there is a frontal cyclone located about 10 degrees to the north of 
Gordon.  This feature, along with the trough, should cause the 
tropical cyclone to turn northward and north-northeastward during 
the next couple of days.  Although Gordon is expected to at least 
briefly  interact with the frontal wave, the global model guidance 
indicates that it will retain its identity and move farther 
north-northeastward over the Atlantic during the forecast period.
The official forecast is shifted a little more to the east of the 
previous NHC prediction and is close to the corrected model 
consensus, HCCA.

Output from the statistical-dynamical SHIPS models shows some 
increase in the low- to mid-level relative humidity and also 
suggests some increase in instability during the forecast period.  
The SHIPS output also shows generally low to moderate vertical 
shear for the next few days.  The official forecast shows some 
restrengthening after 48 hours, but not as much of an intensity 
increase as called for by the SHIPS/LGEM predictions.


FORECAST POSITIONS AND MAX WINDS

INIT  16/2100Z 19.0N  48.5W   30 KT  35 MPH
12H  17/0600Z 19.2N  49.0W   30 KT  35 MPH
24H  17/1800Z 19.7N  49.1W   30 KT  35 MPH
36H  18/0600Z 20.3N  48.8W   30 KT  35 MPH
48H  18/1800Z 21.3N  48.3W   30 KT  35 MPH
60H  19/0600Z 22.8N  47.6W   35 KT  40 MPH
72H  19/1800Z 24.6N  46.5W   40 KT  45 MPH
96H  20/1800Z 27.0N  44.5W   45 KT  50 MPH
120H  21/1800Z 29.0N  43.5W   50 KT  60 MPH

$$
Forecaster Pasch