Tropical Depression Gordon Forecast Discussion Number 20

By | September 16, 2024

000
WTNT42 KNHC 160844
TCDAT2

Tropical Depression Gordon Discussion Number  20
NWS National Hurricane Center Miami FL       AL072024
500 AM AST Mon Sep 16 2024

The convection that developed during the evening hours on the east 
side of Gordon has persisted through the night.  Nighttime CIRA 
proxy vis imagery suggests that the low-level center of Gordon is 
near the western edge of this convection.  Subjective and objective 
intensity estimates range from 25 to 33 kt.  In the absence of 
ASCAT data, no change is made to the 25-kt intensity carried in 
the previous NHC advisory.

The initial motion is estimated to be westward, or 270/7 kt. 
Gordon is being steered westward by the subtropical ridge, situated 
to the north of the tropical depression.  This setup should 
continue to steer Gordon slowly westward through today.  
Thereafter, a frontal low located to the north of the ridge is 
forecast to drop equatorward towards Gordon, creating a weakness 
in the subtropical ridge.  As a result of this steering change, 
Gordon should initially slow its forward motion, and then turn 
toward the north-northeast while gradually accelerating.  The 
consensus track models have continued to shift a bit to the right 
and faster, and the latest NHC forecast is again nudged in that 
direction.

Gordon has been doing a remarkable job fighting off environmental 
dry air given how the area of convection has maintained itself 
overnight relatively close to the low-level center.  Gordon is 
forecast to remain in a dry mid-level environment for the next few 
days, although some slight moistening of the environment is 
possible beyond 24 h while the vertical shear is forecast to remain 
relatively low.  Although it is still possible that Gordon could 
degenerate to a remnant low, if the cyclone is able to survive the 
next 24 h, then its chances of surviving the next 5 days would seem 
to increase.  There is also some uncertainty as to how Gordon's 
circulation could potentially interact with a non-tropical low in 3 
to 4 days.  If Gordon then survives its interaction with the 
non-tropical low, some strengthening would be possible in 4 to 5 
days as shown by some of the global models.  No changes were made to 
the previous NHC intensity prediction, which still assumes Gordon 
will survive in the short term.


FORECAST POSITIONS AND MAX WINDS

INIT  16/0900Z 19.2N  47.5W   25 KT  30 MPH
 12H  16/1800Z 19.1N  48.3W   25 KT  30 MPH
 24H  17/0600Z 19.3N  49.1W   25 KT  30 MPH
 36H  17/1800Z 19.6N  49.5W   25 KT  30 MPH
 48H  18/0600Z 19.9N  49.6W   25 KT  30 MPH
 60H  18/1800Z 20.7N  49.5W   30 KT  35 MPH
 72H  19/0600Z 21.9N  48.9W   30 KT  35 MPH
 96H  20/0600Z 24.6N  47.7W   35 KT  40 MPH
120H  21/0600Z 26.8N  46.3W   40 KT  45 MPH

$$
Forecaster Hagen

Leave a Reply