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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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