Eastern Pacific Basin Tropical Cyclones

Hurricane Kay Forecast Discussion


000
WTPZ42 KNHC 070243
TCDEP2

Hurricane Kay Discussion Number  11
NWS National Hurricane Center Miami FL       EP122022
900 PM MDT Tue Sep 06 2022

Kay looks slightly better organized on satellite imagery with a 
broad eye-like feature surrounded by curved bands of strong 
convection.  Upper-level outflow is strong over all but the 
northwestern portion of the circulation.  The current intensity is 
bumped up slightly to 80 kt which is a compromise between highly 
varied subjective and objective Dvorak estimates.  It should be 
noted there is a greater than usual amount of uncertainty in the 
advisory intensity.

Vertical wind shear on Kay is forecast to be low, and the system is 
expected to remain in a fairly moist mid-level air mass for the next 
few days.  These factors should lead to further short-term 
strengthening.  However, SSTs will be decreasing significantly in 24 
to 36 hours, which will likely result in a weakening trend 
commencing on Thursday.  Later in the forecast period, very cool 
waters should result in Kay becoming a post-tropical cyclone after 
it passes near the northern Baja California in around 96 hours.  
This is consistent with simulated satellite imagery from the global 
models that show little or no associated deep convection around that 
time.  The official intensity forecast is above the guidance 
models, especially for the first half of the forecast period.

Kay continues northwestward, moving at about 320/11 kt.  There is 
little change to the track forecast reasoning.  A ridge to the 
northeast of the cyclone is expected to result in a mostly 
north-northwestward motion for the next few days.  This should bring 
the core of the of Kay very near the west-central Baja California 
coast on Thursday and Friday.  Later in the forecast period, 
low-level ridging is expected to cause the weakening cyclone to turn 
westward.  The NHC track forecast is close to the previous one and 
also close to the corrected multi-model consensus.  

Kay is a very large tropical cyclone.  It is producing an extensive 
area of high seas, with swells affecting portions of southwestern 
Mexico and the southern Baja California peninsula.  Although Kay is 
likely to weaken before it makes its closest approach to the 
west-central coast of the Baja peninsula, it is forecast to remain a 
large and dangerous hurricane through that time.  In addition, high 
wind, surf, and rainfall impacts will extend far from the center so 
users should not focus on the exact forecast track.

KEY MESSAGES:

1. Heavy rainfall from Kay could lead to flash flooding, including
landslides, across portions of the Baja California peninsula and
mainland northwestern Mexico through Friday.

2. Tropical storm conditions are expected over portions of the
Baja California peninsula beginning Wednesday morning, where a
Tropical Storm Warning is in effect.

3. Hurricane conditions are possible along portions of the
west-central Baja California coast on Thursday, where a hurricane
watch has been issued.  Additional tropical storm watches and
warnings for the northern Baja California peninsula could be
required later tonight and Wednesday.


FORECAST POSITIONS AND MAX WINDS

INIT  07/0300Z 19.5N 111.7W   80 KT  90 MPH
 12H  07/1200Z 20.6N 112.6W   90 KT 105 MPH
 24H  08/0000Z 22.5N 113.5W   95 KT 110 MPH
 36H  08/1200Z 24.7N 114.2W   90 KT 105 MPH
 48H  09/0000Z 26.8N 115.1W   80 KT  90 MPH
 60H  09/1200Z 28.5N 116.2W   65 KT  75 MPH
 72H  10/0000Z 30.0N 117.5W   50 KT  60 MPH
 96H  11/0000Z 31.1N 120.2W   35 KT  40 MPH...POST-TROPICAL
120H  12/0000Z 30.8N 121.5W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Pasch



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