Eastern Pacific Basin Tropical Cyclones

Hurricane Orlene Forecast Discussion


000
WTPZ41 KNHC 012033
TCDEP1

Hurricane Orlene Discussion Number  12
NWS National Hurricane Center Miami FL       EP162022
300 PM MDT Sat Oct 01 2022

Orlene has strengthened some since the last advisory.  An Air Force 
Reserve Hurricane Hunter aircraft reported 700-mb flight-level 
winds of 80 kt in the the northeastern eyewall, and reliable- 
looking surface wind estimates of 69-72 kt from the SFMR. The 
central pressure inside the 16-n mi wide eye was 979 mb.  Based on 
these data, the initial intensity is increased to a possibly 
conservative 70 kt.  Data from the aircraft and a recent 
scatterometer overpass show that Orlene remains a small tropical 
cyclone.

Orlene should remain in a generally moist and light-shear 
environment for about the next 18-24 h, and continued steady 
intensification is expected during that time.  The new intensity 
forecast now calls for a peak intensity of 85 kt in about 24 h, a 
slightly higher intensity than the previous forecast.  After that, 
strong southwesterly shear should cause steady to rapid weakening 
until landfall in Mexico.  This should be followed by dissipation 
over the mountains of northwestern Mexico between 72-96 h.  As 
mentioned previously, while it cannot be ruled out that Orlene 
could reach mainland Mexico as a hurricane, the chances of that 
are decreasing based on the guidance and the forecast shear.  The 
new intensity forecast again lies near or at the upper edge of the 
intensity guidance.

Orlene is generally moving slowly northward, 360/4 kt, to the 
west of a mid-level ridge. After about 12 h, the cyclone should turn
north-northeastward in the flow between this ridge and an upper- 
level trough seen in water vapor imagery over northwestern Mexico 
and the northern Baja California peninsula.  This motion is forecast 
to continue until Orlene dissipates over mainland Mexico.  The 
track guidance is fairly tightly clustered together, although the 
GFS remains a bit to the right of the other models after 24 h.  The 
guidance envelope has shifted a little westward since the previous 
advisory, and based on this the new forecast track is again nudged a 
little to the west.  However, the new track lies a little east of 
the various consensus models, between them and the GFS.


Key Messages:

1. Hurricane conditions are expected in the Islas Marias Sunday
night, with tropical storm conditions beginning late Sunday.
Hurricane conditions are possible over portions of west-central
mainland Mexico starting on Monday.  Tropical storm conditions are
expected within the tropical storm warning area along the
west-central coast of Mexico on Sunday. Tropical storm conditions
are possible over other portions of southwestern and west-central
Mexico in the tropical storm watch area tonight or Sunday.

2. Heavy rainfall from Orlene is expected to lead to flash flooding, 
as well as possible landslides in areas of rugged terrain of 
southwest Mexico into Monday evening.


FORECAST POSITIONS AND MAX WINDS

INIT  01/2100Z 17.9N 107.1W   70 KT  80 MPH
 12H  02/0600Z 18.6N 107.0W   80 KT  90 MPH
 24H  02/1800Z 19.7N 106.8W   85 KT 100 MPH
 36H  03/0600Z 20.9N 106.6W   75 KT  85 MPH
 48H  03/1800Z 22.1N 106.2W   65 KT  75 MPH
 60H  04/0600Z 23.1N 105.8W   45 KT  50 MPH...INLAND
 72H  04/1800Z 24.1N 105.2W   25 KT  30 MPH...INLAND
 96H  05/1800Z...DISSIPATED

$$
Forecaster Beven



Source link