Eastern Pacific Basin Tropical Cyclones

Hurricane Rick Forecast Discussion

WTPZ42 KNHC 241445

Hurricane Rick Discussion Number   9
NWS National Hurricane Center Miami FL       EP172021
1000 AM CDT Sun Oct 24 2021

Rick has changed little in organization since last night, with an 
80-100 n mi wide Central Dense Overcast surrounded by some 
convective banding features.  The intensity estimate is held at 75 
kt for this advisory based on a blend of subjective Dvorak 
estimates from TAFB and SAB, along with objective ADT numbers from 
UW-CIMSS.  Upper-level outflow has become less well-defined over 
the southeastern quadrant of the cyclone, suggestive of some 
south-southeasterly shear.

Center fixes indicate that the hurricane continues its fairly slow 
northward motion at around 355/5 kt.  Rick should move northward to 
north-northwestward through a weakness in the subtropical ridge 
over Mexico, and the track guidance shows a slight increase in 
forward speed during the next day or so.  The global models 
show a slight building of a mid-level ridge to the northwest of 
Rick in about 36 hours which could cause the track to bend more to 
the left after landfall.  The official track forecast is very close 
to the previous one and is also very close to the latest NOAA 
corrected-consensus, HCCA, prediction.

Although Rick has been in a seemingly conducive environment for 
strengthening, the hurricane has not intensified much.  This 
reminds us of our limited understanding of tropical cyclone 
intensity change.  Nonetheless, since Rick should remain over warm 
waters and in a fairly moist mid-level atmospheric environment 
before reaching the coast, the official forecast continues to 
call for some strengthening during the next 12 hours or so.  When 
the center nears the coast, some increase in southwesterly shear 
and the interaction with the mountainous land mass of southern 
Mexico could cause some weakening.  After landfall, the cyclone 
will weaken rapidly and the system may lose its identity sooner 
than shown in this forecast.

Key Messages:

1. Rick is forecast to strengthen today and reach the coast of
southern Mexico tonight or early Monday, bringing life-threatening
storm surge and dangerous hurricane-force winds within a portion of
the Hurricane Warning area from Tecpan de Galeana to Punta San
Telmo.  Residents in this area should follow any advice given by
local officials.

2. Rick is expected to bring tropical storm conditions to portions
of the southern and southwestern coasts of Mexico beginning today
from east of Tecpan de Galeana to Acapulco, and by Monday morning
from west of Punta San Telmo to Manzanillo, where a Tropical
Storm Warning is in effect.

3. Heavy rains associated with Rick are expected to move into the
Mexican states of Guerrero and Michoacan today, and could persist
through Tuesday.  This rainfall will likely produce flash
flooding and mudslides.


INIT  24/1500Z 16.1N 101.7W   75 KT  85 MPH
 12H  25/0000Z 16.9N 101.9W   90 KT 105 MPH
 24H  25/1200Z 18.1N 102.3W   80 KT  90 MPH...INLAND
 36H  26/0000Z 19.2N 103.1W   40 KT  45 MPH...INLAND
 48H  26/1200Z 20.4N 104.0W   25 KT  30 MPH...POST-TROP/INLAND
 60H  27/0000Z...DISSIPATED

Forecaster Pasch

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