000
WTPZ42 KNHC 171445
TCDEP2

Tropical Depression Seven-E Discussion Number   1
NWS National Hurricane Center Miami FL       EP072017
1000 AM CDT Mon Jul 17 2017

Recent satellite data indicate that the area of low pressure located
several hundred miles south of Manzanillo, Mexico, has acquired a
well-defined center and the associated deep convection is
sufficiently organized for the system to be classified as a tropical
depression.  This marks the formation of the seventh cyclone of the
eastern Pacific hurricane season.  The system is sheared with the
center located near the northwestern edge of the primary convective
mass.  Earlier ASCAT data revealed believable 25-30 kt winds, and
the initial intensity is set to 30 kt.  The environment ahead of
the cyclone is not ideal for significant strengthening.  Moderate to
strong northwesterly shear is expected to continue for another 24
hours, but is then forecast to lessen late Tuesday when the system
is located in a col area between two large upper level lows.
The shear is expected to become quite strong by day 4 when the
cyclone approaches the westernmost upper low/trough.  This shear,
along with cooler waters, should cause weakening late in the period.

The somewhat uncertain initial motion estimate is 280/5 kt. The
depression is forecast to move westward to west-northwestward to the
south of a mid-level ridge located over northern Mexico and the
western United States.  The track guidance is in relatively good
agreement through 72 hours, but there is significant spread after
that time, due to possible interaction with a disturbance currently
located about 750 n mi west of the depression.  The ECMWF takes the
depression on a more northward track around the northern portion of
the circulation of the western system, while the GFS weakens the
depression and shows it merging with the second disturbance.  Given
the large spread in the guidance, the NHC foreast lies near the TVCN
multi-model consensus and the HFIP corrected consensus at days 4 and
5, and is of low confidence.

FORECAST POSITIONS AND MAX WINDS

INIT  17/1500Z 14.1N 105.1W   30 KT  35 MPH
 12H  18/0000Z 14.4N 106.1W   35 KT  40 MPH
 24H  18/1200Z 14.8N 107.6W   40 KT  45 MPH
 36H  19/0000Z 15.2N 109.4W   40 KT  45 MPH
 48H  19/1200Z 15.7N 111.5W   40 KT  45 MPH
 72H  20/1200Z 16.8N 116.2W   35 KT  40 MPH
 96H  21/1200Z 17.1N 121.4W   30 KT  35 MPH
120H  22/1200Z 17.0N 125.5W   25 KT  30 MPH

$$
Forecaster Brown