000
WTPZ45 KNHC 111458
TCDEP5
 
Hurricane Simon Discussion Number  17
NWS National Hurricane Center Miami FL       EP202026
900 AM CST Sun Oct 11 2026

Simon continues to be a powerful Category 4 hurricane as it gets 
ever closer to the coast of Mexico this morning. Since the previous 
advisory, the eye definition on infrared satellite has cooled 
slightly and the overall central dense overcast related to the 
eyewall convection has been shrinking in size. There was a helpful 
GPM microwave pass at 1152 UTC, showing that the inner core is 
showing some hints of disruption, with a larger outer band becoming 
more dominant on Simon's northwestward side. The 12 UTC subjective 
Dvorak fix was T6.5/125 kt, and the objective satellite estimates 
are in the 119-127 kt range, so the initial intensity is being 
nudged down to 125 kt for this advisory. 

The hurricane has maintained a north-northwestward motion this 
morning, or 345 degrees at 5 kt, bringing the hurricane very close 
to the coast of Mexico. On Simon's current heading, dangerous wind, 
surge, and rainfall effects appear likely over portions of 
west-central Mexico in the Hurricane Warning area today. It also 
remains possible the hurricane makes direct landfall between Playa 
Perula and Cabo Corrientes in the next 12-18 hours. However, like 
the previous forecast cycle, the most reliable guidance aids   
(HCCA, GDMI, WN3I) have shifted westward once again, and the NHC 
track forecast has been shifted in that direction, but due to 
continuity constraints is not shifted all the way to those solutions 
yet. To make matters even more uncertain, there are some 
deterministic global model solutions (00 UTC ECMWF, 06 UTC GFS) that 
show Simon turning southwestward near the end of the forecast 
period, and that is also seen in a handful of the Google DeepMind 
ensemble members. This NHC track continues to favor a track that 
stays closer to the coast of Mexico before going inland into Mexico 
in 72-96 h. Needless to say, this is a low confidence track forecast 
with higher than usual uncertainty given the spread in the 
guidance. 

The intensity forecast also presents challenges. As mentioned in the 
previous discussion, the forecast is sensitive to how close Simon 
passes to western Mexico during the next day or so. A track closer 
to the coast or inland would likely result in more severe disruption 
of Simon's circulation due to the high terrain of the Sierra Madre 
mountains, leading to rapid weakening. However, with the track 
shifting further offshore, this weakening may not be as severe, 
though some negative topographic influence is shown in the majority 
of the guidance leading to weakening. However, like the track, the 
current intensity forecast is low confidence forecast because only a 
small deviation either east or west could result in Simon either 
dissipating after landfall or staying much stronger than the current 
forecast offshore. The NHC intensity forecast is a compromise 
between these extremes. 
 
Key Messages:
 
1. Catastrophic wind and life-threatening storm surge impacts are 
likely along a portion of the west-central coast of Mexico, and a 
Hurricane Warning is in effect from Punta San Telmo to El Roblito. 
Residents should shelter in a safe room to ride out the storm as the 
most significant hazards with Simon are now ongoing.
 
2. Heavy rainfall associated with Simon will impact portions of 
southwestern Mexico through Monday. This rainfall will produce 
life-threatening flooding and mudslides, especially in areas of 
steep terrain.
 
3. Swells will affect portions of the southwestern and west-central
coast of Mexico over the next few days. These swells are likely to
cause life-threatening surf and rip current conditions. Please
consult products from your local weather office.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  11/1500Z 19.2N 105.3W  125 KT 145 MPH...NEAR THE COAST
 12H  12/0000Z 19.9N 105.6W  105 KT 120 MPH...NEAR THE COAST
 24H  12/1200Z 20.5N 106.0W   85 KT 100 MPH...NEAR THE COAST
 36H  13/0000Z 21.1N 106.4W   70 KT  80 MPH
 48H  13/1200Z 21.8N 106.8W   60 KT  70 MPH
 60H  14/0000Z 22.5N 106.9W   50 KT  60 MPH
 72H  14/1200Z 23.0N 106.9W   50 KT  60 MPH
 96H  15/1200Z 23.9N 106.4W   30 KT  35 MPH...POST-TROP/INLAND
120H  16/1200Z...DISSIPATED
 
$$
Forecaster Papin