317
WTPZ41 KNHC 081456
TCDEP1

Hurricane Priscilla Discussion Number  16
NWS National Hurricane Center Miami FL       EP162025
800 AM MST Wed Oct 08 2025

Priscilla has rapidly weakened over the past 12 hours.  Deep
convection in the northern semicircle has become almost
non-existent, and the convection in the southern semicircle has also
decreased in coverage and intensity.  Subjective CI numbers were 75
kt at 12Z, but the final-T numbers were 55 kt.  Objective intensity
estimates from UW-CIMSS have decreased to the 60-70 kt range.
Despite the appearance of the deep convection falling apart, a
recent 37 GHz GPM pass suggests that Priscilla may still be fairly
powerful in the low-levels, below the freezing level, so I have only
brought the intensity down to 65 kt, maintaining Priscilla as a
hurricane for this advisory.  Priscilla is expected to weaken to a
tropical storm within the next few hours.

The initial motion estimate is slowly northwestward, or 310 degrees
at 6 kt.  Priscilla is currently moving along the southwestern
side of a mid-level high pressure ridge near the Texas/Mexico
border.  In 36 hours or so, a large trough or cutoff low near the
California coast should induce a turn toward the north.  By 60
hours, Priscilla will likely have weakened into a shallow cyclone
moving in the low-level environmental flow.  The official track
forecast is very near the previous NHC forecast track through 48 h,
but is notably slower and farther south at 60-72 h, and lies close
to the HFIP Corrected Consensus (HCCA) approach.

Priscilla has weakened faster than anticipated so far, possibly due
to enhanced upwelling of cool water due to the cyclone`s slow
motion.  Sea-surface temperatures will continue to rapidly decrease
along Priscilla`s path, reaching 26 degrees C in about 18 hours.
Priscilla is expected to degenerate into a remnant low in about 60
hours, with dissipation just after 72 hours.  The official intensity
forecast has been lowered from the previous NHC forecast due to the
lower initial intensity, and lies near the middle of the model
guidance suite.


KEY MESSAGES:

1.  Tropical storm conditions are possible along the Baja California
Sur Pacific coastline within the Tropical Storm Watch area today.
Interests elsewhere in the Baja California peninsula should monitor
the progress of Priscilla.

2.  Moisture associated with Priscilla will lead to heavy rainfall
and a flash flood risk across portions of Arizona, Utah, through the
Four Corners into southwest Colorado and far northwest New Mexico
from Thursday into Saturday morning.

3.  Swells generated by Priscilla are affecting portions of the
coast of southwestern and west-central Mexico as well as the coast
of the southern Baja California peninsula. These swells are likely
to cause life-threatening surf and rip current conditions, in
addition to some coastal flooding.


FORECAST POSITIONS AND MAX WINDS

INIT  08/1500Z 21.4N 112.5W   65 KT  75 MPH
 12H  09/0000Z 22.2N 113.6W   55 KT  65 MPH
 24H  09/1200Z 23.3N 114.7W   50 KT  60 MPH
 36H  10/0000Z 24.6N 115.3W   45 KT  50 MPH
 48H  10/1200Z 25.9N 115.5W   35 KT  40 MPH
 60H  11/0000Z 26.8N 115.4W   30 KT  35 MPH...POST-TROP/REMNT LOW
 72H  11/1200Z 27.7N 115.2W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  12/1200Z...DISSIPATED

$$
Forecaster Hagen