Eastern Pacific Basin Tropical Cyclones

Tropical Depression Nineteen-E Forecast Discussion


000
WTPZ44 KNHC 200842
TCDEP4

Tropical Depression Nineteen-E Discussion Number   2
NWS National Hurricane Center Miami FL       EP192022
400 AM CDT Thu Oct 20 2022

The circulation associated with the cyclone does not appear to have 
tightened up yet, and the center is estimated to be located between 
two primary clusters of deep convection.  Dvorak classifications 
are T2.5/35 kt from TAFB and T1.5/25 kt from SAB, and the objective 
ADT estimate from UW-CIMSS is just below tropical storm intensity.  
Therefore, the system remains a depression with maximum winds 
estimated to be 30 kt.

TAFB and SAB center fixes suggest the depression isn't moving very 
fast.  The initial motion is westward, or 275/3 kt, with the system 
just beginning to move along the southern edge of a mid-tropospheric 
high centered near the mouth of the Gulf of California.  This high 
is expected to slide eastward across Mexico during the next 3 days, 
while a deep-layer area of low pressure moves very little well to 
the west of the Baja California peninsula.  The cyclone should 
slowly recurve around the western periphery of the high, eventually 
moving northward near the west-central coast of Mexico by Saturday 
night and then accelerating north-northeastward over Mexico on 
Sunday.  There is a typical amount of spread among the track models 
for this forecast, with most of the discrepancies related to how 
wide and fast a turn the cyclone makes while recurving around the 
high.  The NHC official forecast favors a more intense cyclone that 
makes a tighter, faster turn, and it lies closest to the solutions 
of the GFS, COAMPS-TC, and HCCA consensus aid.  This forecast 
essentially lies on top of the previous NHC prediction.

An environment of negligible deep-layer shear, very warm ocean 
temperatures, and sufficient atmospheric moisture should support 
steady strengthening in the coming days.  The cyclone's peak 
intensity will likely be dictated by exactly how long the system 
will be over water before reaching land, and it could also be 
modulated by some increase in shear in about 3 days.  For 
continuity's sake, the NHC intensity forecast is mostly unchanged 
from the previous prediction, and it most closely follows the HCCA 
intensity solution, which is near the upper end of the guidance 
envelope.  After the system moves inland, rapid weakening is 
expected, and the low-level circulation is forecast to dissipate 
over the mountainous terrain of Mexico by early Monday.  Global 
model fields indicate that the mid-level remnants will continue 
northeastward across northern Mexico on Monday.


Key Messages:

1. The depression is forecast to become a hurricane before it passes 
near or over the west-central coast of Mexico late Saturday and 
Sunday, accompanied by strong winds and a potentially dangerous 
storm surge.  Interests along the coast of southwestern and 
west-central Mexico should closely monitor the progress of this 
system, and hurricane or tropical storm watches could be required 
for portions of this coastline later today.

2. Heavy rainfall could lead to flash flooding and possible 
landslides in areas of rugged terrain over coastal southwestern 
Mexico.


FORECAST POSITIONS AND MAX WINDS

INIT  20/0900Z 15.1N 101.5W   30 KT  35 MPH
 12H  20/1800Z 15.3N 102.3W   40 KT  45 MPH
 24H  21/0600Z 15.6N 103.3W   50 KT  60 MPH
 36H  21/1800Z 16.1N 104.2W   60 KT  70 MPH
 48H  22/0600Z 16.8N 105.2W   70 KT  80 MPH
 60H  22/1800Z 17.9N 106.0W   80 KT  90 MPH
 72H  23/0600Z 19.4N 106.2W   90 KT 105 MPH
 96H  24/0600Z 23.4N 104.3W   50 KT  60 MPH...INLAND
120H  25/0600Z...DISSIPATED

$$
Forecaster Berg



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