Tropical Cyclone Discussion

031
WTPZ42 KNHC 290233
TCDEP2
 
Tropical Depression Vance Discussion Number  31
NWS National Hurricane Center Miami FL       EP222026
800 PM MST Wed Oct 28 2026

As anticipated, Vance's deep convection has re-ignited this evening, 
with cloud top temperatures as cold as -80 degrees C. This 
convective activity has pulled at the storm's center of circulation 
as well, with earlier visible satellite imagery showing the center 
briefly becoming obscured. TAFB's subjective Dvorak intensity 
estimate remains at a 2.0 for a final T number, with objective 
estimates from UW-CIMSS ranging from 27-36 kt. Based on these data, 
Vance's initial intensity is held steady at 30 kt, though its 
possible higher gusts could be present within the deep convection.

With this convective redevelopment, Vance has turned to the 
north-northeast with a somewhat faster forward motion, estimated at 
025/11 kt. Vance is being steered by a broad trough centered over 
the eastern Pacific, and is expected to turn back to the north once 
convection wanes on Thursday. The latest NHC track forecast reflects 
largely a blend of the HCCA and TVCN models, and is a little east of 
the previous track, partially due to adjustments in the initial 
position. 

Strong vertical wind shear will continue to erode Vance's core over 
the next 24 hours. Simulated satellite imagery from the GFS and 
ECMWF suggests that the ongoing convection, expected to last most of 
overnight, will be Vance's last gasp before it is fully sheared off, 
leading to the cyclone becoming a post-tropical remnant low during 
the latter half of tomorrow. Vance is then expected to dissipate 
shortly thereafter as it interacts with mountainous terrain along 
the western Mexican coastline. The latest NHC intensity forecast 
depicts slight weakening after Vance's convective max tonight, 
before weakening into a post-tropical remnant low by tomorrow 
evening.
 

Key Message:

1. Periods of heavy rainfall associated with Vance will impact 
portions of western Mexico during much of this week. This rainfall 
may produce flooding and mudslides across central and southern 
Sinaloa, far southwestern Durango, and far northwestern Nayarit, 
especially in areas along steep terrain.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  29/0300Z 21.1N 108.1W   30 KT  35 MPH
 12H  29/1200Z 22.2N 107.6W   30 KT  35 MPH
 24H  30/0000Z 23.7N 107.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
 36H  30/1200Z 25.2N 108.1W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  31/0000Z...DISSIPATED