Eastern Pacific Basin Tropical Cyclones

Hurricane Kay Forecast Discussion


000
WTPZ42 KNHC 072043
TCDEP2

Hurricane Kay Discussion Number  14
NWS National Hurricane Center Miami FL       EP122022
300 PM MDT Wed Sep 07 2022

After getting better organized this morning, the window for Kay to 
intensify may be closing as the center has reached an area where 
the sea surface temperatures have decreased to 26C.  Data from an 
Air Force Reserve Hurricane Hunter aircraft showed that the central 
pressure was near 971 mb, but that the maximum 700-mb flight level 
winds were only 82 kt, with lower surface winds estimates from the 
SFMR.  The aircraft also reported a decay of the eyewall structure 
during the mission, which is matched by a decay in the eye and 
eyewall structure seen in satellite imagery.  The initial intensity 
is reduced to 85 kt, and this could be a bit generous.

The forecast track takes the center over progressively cooler water 
during the next several days, and continued steady weakening is 
expected. However, the weakening may be slower than normal since 
part of the large circulation will be over the warm Gulf of 
California.  Kay is still forecast to be a hurricane when it passes 
near or over the western portion of the Baja California Peninsula in 
24-36 h.  After that, the cyclone should weaken below hurricane 
strength by 48 h and below tropical storm strength after 72 h.  The 
new intensity forecast shows lower intensities than the previous 
forecast and lies close to the intensity consensus models. 

The initial motion is north-northwestward or 340/11 kt.  A 
mid-level ridge to the north and northeast of the hurricane should 
continue to steer Kay generally north-northwestward for the next 48 
h or so, taking the core of Kay very near or over the west-central 
Baja California peninsula on Thursday and Friday. After that, the 
weakening and increasingly shallow Kay is forecast to turn more 
westward, and eventually southward, away from land as it becomes 
steered by the flow on the south and east side of a low-level ridge 
over the northeastern Pacific.  There has been little change in the 
track guidance since the previous advisory, and the new official 
forecast track has only minor adjustments from the previous 
forecast.

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 landfall or moves very close 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. As the center of Kay passes just offshore, heavy rainfall could 
lead to flash flooding, including landslides, across the Baja 
California peninsula and portions of mainland northwestern Mexico 
through Saturday morning.  Flash, urban, and small stream flooding 
is possible across Southern California, especially in and near the 
peninsular ranges, and Southwest Arizona, Friday night into 
Saturday.

2. Hurricane conditions are expected along portions of the
west-central Baja California coast on Thursday and Thursday night,
and a hurricane warning is in effect for that area.

3. Tropical storm conditions are beginning over portions of the
Baja California peninsula, and these conditions are expected
to spread northward during the next day or so, where a
Tropical Storm Warning is in effect.


FORECAST POSITIONS AND MAX WINDS

INIT  07/2100Z 22.0N 113.0W   85 KT 100 MPH
 12H  08/0600Z 23.8N 113.5W   80 KT  90 MPH
 24H  08/1800Z 26.1N 114.5W   75 KT  85 MPH
 36H  09/0600Z 28.2N 115.5W   65 KT  75 MPH
 48H  09/1800Z 29.8N 116.8W   55 KT  65 MPH
 60H  10/0600Z 30.8N 118.3W   45 KT  50 MPH
 72H  10/1800Z 31.2N 119.6W   35 KT  40 MPH
 96H  11/1800Z 31.0N 121.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  12/1800Z 29.0N 121.5W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Beven



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