000
WTNT42 KNHC 252034
TCDAT2
 
Post-Tropical Cyclone Gabrielle Discussion Number  36
NWS National Hurricane Center Miami FL       AL072025
900 PM GMT Thu Sep 25 2025
 
Gabrielle has quickly lost tropical characteristics today in a 
highly sheared environment. Dry air infiltrating the circulation has 
left the low-level center partially exposed, and the overall cloud 
pattern has become more linear ahead of an approaching baroclinic 
system. Since Gabrielle no longer has organized deep convection and 
is beginning to interact with fronts, it is best designated as a 
post-tropical cyclone. The initial intensity is set at 60 kt based 
on earlier ASCAT data and the latest GFS and ECMWF wind fields. 
Weather radar data from Flores Island in the Azores indicate showers 
are spreading across the northwestern islands as conditions begin 
to deteriorate.

The cyclone continues moving quickly eastward (080/26 kt) within 
strong westerly mid-latitude flow. The center of Gabrielle will pass 
quickly near or over the Azores later tonight and early Friday. 
Gabrielle is forecast to gradually decelerate over the next few 
days while eventually turning southeastward as a ridge builds to 
the west over the eastern Atlantic. As a result, the post-tropical 
cyclone should pass near or over the coast of Portugal later this 
weekend. No significant changes were made to the NHC track forecast 
with this update.

The global models continue to show some increase in Gabrielle's peak 
winds tonight as the cyclone interacts with an approaching 
baroclinic system and completes extratropical transition. The NHC 
intensity forecast favors this solution and shows Gabrielle as a 
65-kt post-tropical cyclone moving through the Azores early Friday. 
Thereafter, steady weakening is forecast as the low becomes 
vertically stacked and fills over the far eastern Atlantic. The 
global models are in good agreement on this solution.  

A Hurricane Warning remains in effect for the islands of the 
Azores. The NHC will continue to issue forecasts on Gabrielle as a 
post-tropical cyclone until the threat to the Azores has ended.
 
 
KEY MESSAGES:
 
1.  Gabrielle is expected to bring hurricane conditions to the
islands of the Azores later tonight and early Friday. Significant
hurricane-force wind gusts are likely across portions of the Azores
even after the center passes.
 
2.  A dangerous storm surge is expected to produce significant
coastal flooding in areas of onshore winds in the Azores. The
surge will be accompanied by large and destructive waves.
 
3.  Heavy rainfall from Gabrielle could produce flash flooding
across the terrain of the central Azores tonight through Friday
morning.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  25/2100Z 37.1N  31.7W   60 KT  70 MPH...POST-TROPICAL
 12H  26/0600Z 38.3N  27.4W   65 KT  75 MPH...POST-TROP/EXTRATROP
 24H  26/1800Z 39.7N  21.9W   60 KT  70 MPH...POST-TROP/EXTRATROP
 36H  27/0600Z 40.3N  16.7W   50 KT  60 MPH...POST-TROP/EXTRATROP
 48H  27/1800Z 40.0N  12.7W   45 KT  50 MPH...POST-TROP/EXTRATROP
 60H  28/0600Z 38.7N  10.1W   35 KT  40 MPH...POST-TROP/EXTRATROP
 72H  28/1800Z 36.9N   8.2W   30 KT  35 MPH...POST-TROP/EXTRATROP
 96H  29/1800Z 35.5N   7.5W   25 KT  30 MPH...POST-TROP/EXTRATROP
120H  30/1800Z...DISSIPATED
 
$$
Forecaster Reinhart