Eastern Pacific Basin Tropical Cyclones

Tropical Depression Three-E Forecast Discussion


159 
WTPZ43 KNHC 170837
TCDEP3

Tropical Depression Three-E Discussion Number   3
NWS National Hurricane Center Miami FL       EP032022
400 AM CDT Fri Jun 17 2022

Satellite imagery indicates that there has not been much change in 
the organization of Tropical Depression Three-E since the last 
advisory, with the system maintaining a small cluster of convection 
near and south of the center.  However, scatterometer data and a 
GMI microwave overpass showed that the center was a bit to the east 
of the previous advisory position.  Subjective and objective 
satellite intensity estimates are in the 30-40 kt range, while the 
scatterometer data showed winds of 25-30 kt.  Based on this, the 
initial intensity is held at a possibly conservative 30 kt.

The initial motion is a somewhat uncertain 360/4. The depression is 
currently in an area of weak steering currents associated with a 
large low-level cyclonic gyre over Central America.  This should 
allow a slow northward motion to continue for the next 12-24 h.  
After that, a building mid- to upper-level ridge north of the 
cyclone should cause a turn toward the west, with a general 
westward motion continuing through the forecast period. The new 
forecast track has some adjustments from the previous track in the 
first 24-36 h based on the more easterly initial position.  By the 
end of the forecast period, though, it is similar to the previous 
track.  The new track is north of the consensus models from 36-72 
h, and this part of the forecast may need some southward adjustment 
in subsequent advisories.

Conditions appear favorable for the cyclone to strengthen during 
the next 12-24 h, and the intensity forecast calls for it to become 
a tropical storm during this time.  After that, the global models 
are in good agreement that moderate to strong easterly shear is 
going to develop over the system.  The intensity guidance shows 
some spread, with some models showing little or no strengthening 
from 24-120 h while others forecast gradual strengthening.  Since 
the cyclone will be moving over increasing sea surface temperatures 
in a moist environment with strong upper-level divergence, the 
intensity forecast calls for some gradual strengthening in spite of 
the shear from 24-120 h.

Interests along the coasts of El Salvador, Honduras, and 
southeastern Mexico should monitor the progress of this system.  
While the cyclone is expected to stay offshore, any motion to the 
north of the current forecast track, or a system that gets larger 
than forecast, would require a tropical storm watch or warning for 
part of this area.  Heavy rains are likely over portions of Central 
America regardless of how close the forecast tropical-storm force 
winds get to the coast.


FORECAST POSITIONS AND MAX WINDS

INIT  17/0900Z 11.3N  89.6W   30 KT  35 MPH
 12H  17/1800Z 11.8N  89.5W   35 KT  40 MPH
 24H  18/0600Z 12.2N  89.8W   40 KT  45 MPH
 36H  18/1800Z 12.4N  90.2W   40 KT  45 MPH
 48H  19/0600Z 12.5N  91.0W   45 KT  50 MPH
 60H  19/1800Z 12.4N  92.1W   45 KT  50 MPH
 72H  20/0600Z 12.2N  93.6W   45 KT  50 MPH
 96H  21/0600Z 12.5N  97.0W   50 KT  60 MPH
120H  22/0600Z 13.5N 101.5W   55 KT  65 MPH

$$
Forecaster Beven




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