410 
WTPZ42 KNHC 010234
TCDEP2

Tropical Depression Seventeen-E Discussion Number   1
NWS National Hurricane Center Miami FL       EP172018
900 PM MDT Fri Aug 31 2018

Satellite images indicate that the low pressure system located a
little more than 400 miles southwest of Manzanillo, Mexico, has
developed organized deep convection and a well-defined center.
Therefore, the system now qualifies as a tropical depression, the
seventeenth one of the busy 2018 eastern North Pacific hurricane
season.  The center of the system is estimated to be near the
northeastern portion of the deep convection based on recent
microwave data.  The initial intensity is set at 30 kt, in agreement
with a Dvorak classification from TAFB.

The initial motion of the depression is highly uncertain since it
only recently formed, but my best guess is 285/9.  The system is
expected to move a little slower to the west-northwest or northwest
during the next couple of days while it remains to the south of a
weakness in the subtropical ridge.  Beyond that time, the
subtropical ridge is expected to build to the north of the tropical
cyclone, and that should cause it to turn more westward and increase
in forward speed.  The models agree on this overall scenario, but
there is a fair amount of cross-track (north-south) spread.  The NHC
track forecast lies close to the middle of the guidance envelope
near the various consensus models.

The depression is currently experiencing some northeasterly shear,
and that should limit the strengthening process overnight.  However,
the models show the upper-level pattern becoming quite favorable
this weekend.  The expected decrease in shear combined with warm
SSTs and a moist environment should allow the system to steadily
strengthen for most of the forecast period. The NHC intensity
forecast is a little lower than the HCCA model in the short term,
but leans heavily on that guidance from 48 hours and beyond.  It
should also be noted that the GFS, UKMET, and ECMWF models all show
this system deepening significantly during the next several days,
which is a good indication that this cyclone will likely become
another significant hurricane.

FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 14.3N 108.4W   30 KT  35 MPH
 12H  01/1200Z 15.0N 109.5W   30 KT  35 MPH
 24H  02/0000Z 15.6N 110.5W   40 KT  45 MPH
 36H  02/1200Z 16.1N 111.5W   45 KT  50 MPH
 48H  03/0000Z 16.6N 112.7W   60 KT  70 MPH
 72H  04/0000Z 17.0N 115.0W   75 KT  85 MPH
 96H  05/0000Z 17.4N 118.3W   85 KT 100 MPH
120H  06/0000Z 18.3N 122.6W   95 KT 110 MPH

$$
Forecaster Cangialosi