Eastern Pacific Basin Tropical Cyclones

Hurricane Kay Forecast Discussion


ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM

Hurricane Kay Discussion Number   7
NWS National Hurricane Center Miami FL       EP122022
900 PM MDT Mon Sep 05 2022

Kay was upgraded to a hurricane earlier today based on valuable data 
that was received from the Air Force Hurricane Hunters just before 
the previous advisory issuance. The aircraft reported dropsonde data 
that supported a minimum pressure around 980 mb, along with 
flight-level winds of 85 kt at 850 mb and SFMR winds up to 71 kt in 
the eastern portion of the cyclone. There were some earlier hints of 
a ragged eye trying to emerge in visible imagery, but the center is 
still obscured by a small central dense overcast. The inner core 
structure of the cyclone does not appear to have improved much based 
on a couple of recent passive microwave overpasses, as some dry air 
has wrapped into the western and southern portions of the 
circulation. Based on the earlier aircraft data, the intensity of 
Kay is held at 70 kt for this advisory. 

The hurricane is moving west-northwestward at 285/9 kt. The track 
guidance for Kay over the next few days remains in good agreement. 
Kay is expected to turn northwestward on Tuesday and then 
north-northwestward by early Wednesday while moving toward or to the 
west of the Baja California peninsula. While the core of the storm 
is still forecast to remain offshore, the large wind field could 
bring tropical-storm-force winds to the southern portion of Baja 
California by early Wednesday. The hurricane is forecast to make its 
closest approach to the west-central portion of Baja California late 
Thursday into Friday. The official NHC forecast lies very close to 
the HFIP corrected consensus approach (HCCA) and has been nudged 
slightly to the right of the previous one. It is noted that the GFS 
and ECMWF still lie on the eastern edge of the guidance envelope.   

Kay has significantly strengthened today despite some moderate 
northeasterly deep-layer shear diagnosed by the SHIPS guidance over 
the system. This shear is forecast to diminish in a day or so, while 
Kay remains over very warm SSTs and in a moist and unstable 
environment. Thus, more strengthening is anticipated and Kay could 
approach major hurricane strength in 36-48 h. The official NHC 
forecast is very similar to the previous one and lies slightly above 
the IVCN aid and closer to HCCA. By early Thursday, drier air and 
cooler SSTs at higher latitudes will cause Kay to begin weakening. 
The cyclone is forecast to lose its organized convection and become 
a post-tropical low by day 5.

The government of Mexico has extended the Tropical Storm Watch 
northward from Puerto San Andresito to Punta Abreojos. Additional 
tropical storm or hurricane watches or warnings could be necessary 
for portions of Baja California later tonight or on Tuesday.

KEY MESSAGES:

1. Gusts to tropical-storm-force and rough surf along the coast of 
southwestern Mexico are expected through Tuesday.  In addition, 
heavy rainfall from Kay could lead to flash flooding, including 
landslides, across portions of the Mexican Riviera and western 
Mexico through Wednesday night.

2. Tropical storm conditions are possible across the southern Baja 
California peninsula by early Wednesday, where a Tropical Storm 
Watch has been issued. 

3. While the details of the long-range track and intensity forecasts 
remain uncertain, there is increasing risk of significant wind, 
surf, and rainfall impacts across the central portion of the Baja 
California peninsula later this week.  A tropical storm or hurricane 
watch could be issued for that region by Tuesday.


FORECAST POSITIONS AND MAX WINDS

INIT  06/0300Z 16.0N 108.1W   70 KT  80 MPH
 12H  06/1200Z 17.1N 109.6W   80 KT  90 MPH
 24H  07/0000Z 18.3N 111.2W   90 KT 105 MPH
 36H  07/1200Z 19.9N 112.5W   95 KT 110 MPH
 48H  08/0000Z 21.7N 113.4W   95 KT 110 MPH
 60H  08/1200Z 23.7N 114.1W   85 KT 100 MPH
 72H  09/0000Z 25.6N 115.0W   75 KT  85 MPH
 96H  10/0000Z 28.5N 116.8W   50 KT  60 MPH
120H  11/0000Z 30.0N 120.0W   35 KT  40 MPH...POST-TROPICAL

$$
Forecaster Reinhart

NNNN



Source link