Tropical Cyclone Discussion

799
WTNT42 KNHC 252037
TCDAT2
 
Tropical Storm Gonzalo Discussion Number   4
NWS National Hurricane Center Miami FL       AL072026
800 PM CVT Fri Sep 25 2026
 
The overall structure of Gonzalo has changed little today.  The 
circulation is elongated from the north-northeast to south-southwest 
with the advisory position set as a mean between a couple of 
low-level vorticity centers on either end of the elongated center. 
Deep convection remains displaced well to the northeast of the 
estimated center due to moderate to strong southwesterly shear.  
Objective and subjective satellite intensity estimates have not 
changed much, therefore the initial intensity remains 45 kt, in line 
with the earlier scatterometer data.
 
Gonzalo has been moving more northward today with an initial motion 
estimate of 350/10 kt.  The storm is expected to be steered 
northward to north-northwestward during the next couple of days 
between a mid-level trough to its north and a ridge over western 
Africa.  Gonzalo's forward speed is expected to decrease as the 
system becomes increasingly shallow and is steered by the weaker 
low-level flow. The new official track forecast is similar to the 
previous advisory and lies closest to the latest Google Deep Mind 
ensemble prediction.
 
The vertical shear over Gonzalo is forecast to increase 
significantly on Saturday and with gradually decreasing sea surface 
temperatures along the forecast track, weakening should begin by 
Saturday morning.  Simulated satellite imagery from the global 
models indicate that Gonzalo will lose organized deep convection in 
24 to 36 hours, and the new NHC forecast shows the system becoming a 
post-tropical remnant low by Sunday morning. The intensity forecast 
is in best agreement with the typically reliable consensus aids. 
 
Key Messages:
 
1. Tropical storm conditions will continue across portions of the
Cabo Verde Islands tonight.
 
2. Heavy rains from Gonzalo could affect the eastern portions of
the Cabo Verde Islands and the western coast of Africa between
Guinea-Bissau to Senegal through Saturday. Areas of flash flooding
will be possible along the Africa coast with some isolated flash
flood concerns for the eastern islands of Cabo Verde.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  25/2100Z 16.2N  22.7W   45 KT  50 MPH
 12H  26/0600Z 17.6N  22.9W   45 KT  50 MPH
 24H  26/1800Z 19.0N  23.3W   35 KT  40 MPH
 36H  27/0600Z 20.0N  23.5W   30 KT  35 MPH...POST-TROP/REMNT LOW
 48H  27/1800Z 20.6N  23.9W   25 KT  30 MPH...POST-TROP/REMNT LOW
 60H  28/0600Z 21.2N  24.3W   20 KT  25 MPH...POST-TROP/REMNT LOW
 72H  28/1800Z 21.7N  24.6W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  29/1800Z 22.0N  25.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  30/1800Z...DISSIPATED