000
WTPZ43 KNHC 220249
TCDEP3

TROPICAL DEPRESSION EIGHT-E DISCUSSION NUMBER   2
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP082016
800 PM PDT THU JUL 21 2016

Visible satellite imagery and a 2309 UTC SSMIS microwave overpass
showed that the depression's center of circulation was located near
the northeastern edge of the cloud mass, indicative that some
northeasterly shear is impinging on the cloud pattern.  The Dvorak
satellite intensity estimates have not changed during the past 6
hours, and the initial intensity remains at 30 kt.  Light to
moderate northeasterly shear is expected to continue for the next
couple of days as the depression traverses warm water.  Gradual
strengthening seems reasonable and this forecast trend is supported
by most of the statistical-dynamical guidance.  Beyond day 3,
however, the depression is expected to encounter decreasing SSTs of
below 25C, and move into a more stable thermodynamic environment
which should influence slow weakening through the remainder of the
period.  The latest NHC forecast is similar to the previous one, and
is based primarily on the IVCN multi-model guidance.

Conventional satellite position fixes and a couple of microwave
overpasses yield an initial motion estimate of 295/11 kt, south of
a strong subtropical ridge along 29N originating from Texas/northern
Mexico.  This ridge is expected to steer the cyclone generally
west-northwestward through the 96 hour period.  Afterward, the
global and regional model guidance still shows increasing spread
with time.  The ECMWF is basically the outlier this evening, showing
a much more north-northwestward turn into a break in the ridge
created by a combination of a digging upper-level low, and Tropical
Storm Frank to the northeast of the depression.  All the other
guidance agree more with a gradual turn toward the northwest through
day 5.  The official forecast splits these two solutions, but is
hedged a bit toward the model cluster reflecting a less poleward
turn.


FORECAST POSITIONS AND MAX WINDS

INIT  22/0300Z 11.6N 115.0W   30 KT  35 MPH
 12H  22/1200Z 12.3N 116.5W   40 KT  45 MPH
 24H  23/0000Z 13.1N 118.6W   50 KT  60 MPH
 36H  23/1200Z 13.8N 120.7W   55 KT  65 MPH
 48H  24/0000Z 14.4N 122.5W   60 KT  70 MPH
 72H  25/0000Z 16.0N 125.4W   70 KT  80 MPH
 96H  26/0000Z 17.4N 127.7W   65 KT  75 MPH
120H  27/0000Z 18.3N 129.1W   55 KT  65 MPH

$$
Forecaster Roberts