Pacific Hurricane Feed

Hurricane Kay Forecast Discussion



313 
WTPZ42 KNHC 080851
TCDEP2

Hurricane Kay Discussion Number  16
NWS National Hurricane Center Miami FL       EP122022
300 AM MDT Thu Sep 08 2022

The satellite presentation of Kay has gradually degraded overnight
with the eye becoming less defined, and the deepest convection
confined to the southeastern and eastern portions of the
circulation.  An Air Force Reserve reconnaissance aircraft that 
investigated Kay overnight has measured peak 700-mb flight-level 
winds of 78 kt.  Unfortunately the SFMR data appeared 
unrepresentative as compared to corresponding dropsonde surface 
winds and recent scatterometer data.  As a result, there is higher 
uncertainty in how much the flight-level winds are mixing to the 
surface.  The initial intensity has been conservatively reduced to 
75 kt, which is a blend of the flight-level reduced winds, and 
recent satellite intensity estimates.  The aircraft reported a 
minimum pressure of 974 mb on its final pass through the center. 

Kay has crossed the 26 degree Celsius isotherm and will be 
traversing progressively cooler SSTs over the next couple of days.  
That, along with a gradually drying mid-level air mass, is expected 
to cause gradual weakening over the next couple of days. However, 
Kay is forecast to remain a hurricane when it passes near or over 
the west-central coast of the Baja California peninsula later 
today, and remain a tropical storm as it passes just west of the 
northwestern portion of the peninsula on Friday.  Simulated 
satellite imagery from the global models suggest the convection 
will wane on Saturday, and Kay is forecast to become post-tropical 
at that time.  The new NHC intensity forecast calls for slightly 
faster rate of weakening than before, and is near the IVCN and HCCA 
consensus aids. 

Kay continues to move north-northwestward or 345/12 kt. A mid-level 
ridge to the east of Kay should steer it on a north-northwestward 
heading during the next 24 to 36 hours.  After that time, a weaker 
and more vertically shallow Kay is expected to turn more westward, 
and eventually southward to the southeast of a low-level ridge over 
the eastern Pacific.  The NHC track forecast lies near the HFIP 
corrected consensus model, and is quite similar to the previous 
official forecast. 

Kay is a very large tropical cyclone. It is producing an extensive
area of high seas, with swells affecting portions of southwestern
Mexico, the Gulf of California, and the 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 near or over the Baja California 
peninsula, 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 into Saturday.

2. Hurricane conditions are expected along portions of the
west-central Baja California coast later this morning through 
this evening, and a hurricane warning is in effect for that area.

3. Tropical storm conditions are occurring 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  08/0900Z 24.5N 113.4W   75 KT  85 MPH
 12H  08/1800Z 26.5N 114.1W   65 KT  75 MPH
 24H  09/0600Z 28.7N 115.4W   55 KT  65 MPH
 36H  09/1800Z 30.5N 116.8W   45 KT  50 MPH
 48H  10/0600Z 31.4N 118.4W   40 KT  45 MPH
 60H  10/1800Z 31.7N 119.5W   35 KT  40 MPH...POST-TROPICAL
 72H  11/0600Z 31.7N 120.4W   30 KT  35 MPH...POST-TROP/REMNT LOW
 96H  12/0600Z 30.3N 120.9W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  13/0600Z 28.7N 120.0W   15 KT  15 MPH...POST-TROP/REMNT LOW

$$
Forecaster Brown




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