Advisories

000
WTPZ45 KNHC 141449
TCDEP5
 
Hurricane Simon Discussion Number  29
NWS National Hurricane Center Miami FL       EP202026
800 AM MST Wed Oct 14 2026
 
First-light visible imagery indicates that Simon has continued to
lose organization during the last several hours. The low-level
center is now located near the northern edge of the convective
overcast due to the effects of northerly shear. However, there is
still no microwave imagery of the storm to better diagnose the
internal structure. The satellite intensity estimates have trended
down, and based on this the initial intensity is reduced to a
possibly generous 80 kt.
 
The hurricane continues drifting southwest or 230/2 kt. For the
next day or two, Simon is likely to continue drifting southwestward
in an area of light steering currents, with the center remaining
well offshore. After that time, the track forecast becomes less
confident. While all of the global models agree that a mid- to
upper-level trough should form west of Baja California after 48 h,
there is poor agreement on the track forecasts for Simon during
this time. The GFS and the regional hurricane models forecast that
Simon will continue moving southward or southwestward through 72 h,
followed by a slow movement toward the northwest. The remainder of
the guidance favors a northwestward or north-northwestward turn
between 36-48 h, with that motion continuing through the end of the
forecast period. The new track forecast follows the latter scenario 
in anticipation that the center will try to follow convective bursts 
displaced to the north by southerly shear. The new forecast track is 
again adjusted west of the previous track, but it lies to the east 
of the HCCA corrected consensus and the Google DeepMind ensemble 
mean.
 
Simon's small size makes it susceptible to intensity fluctuations
based on the state of its compact inner core and small changes in
the environmental conditions. The current northerly shear is
forecast to diminish during the next 12-24 h, which may allow some
modest re-intensification. By 36 h, increasing southerly to
southwesterly upper-level flow between the trough to the northwest
and Tropical Storm Trudy to the southeast should cause significant
shear and aid in the entrainment of dry air. This should cause
steady weakening, with Simon expected to weaken to a tropical storm
as it approaches Baja California Sur. The system is likely to decay
to a remnant low by 120 h as the shear and dry air cause the
convection to dissipate.
 
Simon continues to be a challenging storm to forecast, and
confidence remains lower than normal given the weak steering,
proximity to land, very small size, and significant model spread.
 
Key Messages:
 
1. While Simon is no longer expected to bring hurricane conditions
to Las Islas Marias, interests in west-central Mexico and Baja
California Sur should continue to closely monitor the latest
updates. Watches or warnings could be required for portions of Baja
California Sur over the next day or two.
 
2. Large swells will likely affect portions of the coast of
west-central Mexico and Baja California Sur over the next several
days. These swells could cause life-threatening surf and rip current
conditions.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  14/1500Z 19.7N 108.1W   80 KT  90 MPH
 12H  15/0000Z 19.5N 108.3W   85 KT 100 MPH
 24H  15/1200Z 19.3N 108.3W   85 KT 100 MPH
 36H  16/0000Z 19.2N 108.3W   80 KT  90 MPH
 48H  16/1200Z 19.9N 108.7W   75 KT  85 MPH
 60H  17/0000Z 21.2N 109.7W   65 KT  75 MPH
 72H  17/1200Z 22.6N 110.6W   50 KT  60 MPH
 96H  18/1200Z 24.5N 112.2W   35 KT  40 MPH
120H  19/1200Z 26.9N 113.6W   25 KT  30 MPH...POST-TROP/REMNT LOW
 
$$
Forecaster Beven