000
WTPZ45 KNHC 061431
TCDEP5

HURRICANE JULIO DISCUSSION NUMBER  11
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP102014
800 AM PDT WED AUG 06 2014

Julio has a somewhat ragged appearance in satellite imagery this
morning.  While cloud tops near the center are about -80C, AMSR-2
microwave imagery a few hours ago showed that the eyewall was open
to the north.  That, combined with a large arc cloud seen moving
northward away from the center, suggests that dry air entrainment is
occurring on the north side.  Satellite intensity estimates are 77
kt from TAFB and 65 kt from SAB.  Given the current appearance, the
initial intensity remains 65 kt.  The cirrus outflow is good over
the southwestern semicircle and poor elsewhere.

The initial motion is still 285/15, and there is no change to the
forecast philosophy from the previous advisory.  The NHC model
guidance is in good agreement on Julio moving along the southern
periphery of a deep-layer ridge to its north for the next 72 hours
or so. After that, a break in the ridge is forecast to develop north
of the Hawaiian Islands, and Julio is expected to turn more
northwestward and pass north of the Islands.  There is some spread
in the guidance by 96-120 hours.  The ECMWF, UKMET, and GFDL are on
the south side of the guidance envelope forecasting a track closer
to Hawaii, while the GFS, GFS Ensemble Mean, and Canadian models are
on the right side of the guidance envelope.  The center of the
envelope and the consensus models are very close to the previous
forecast, and thus the new forecast track is almost identical to the
previous forecast.

Julio is in an environment of light vertical wind shear, and it
should remain over sea surface temperatures of 26C or warmer for the
next 12-24 hours.  This should allow some strengthening if the
storm can fight off the current dry air intrusion.  After that, the
cyclone is forecast to move over sea surface temperatures of
25C-26C, which should cause some weakening.  There is disagreement
in the dynamical models about how much shear Julio should encounter
while over the cooler water, particularly near the Hawaiian
Islands. The UKMET forecasts stronger shear, while the GFS/ECMWF are
forecasting less shear.  The intensity forecast leans toward the
GFS/ECMWF scenario and thus calls for Julio to slowly weaken after
36 hours.  The new forecast has minor adjustments from the previous
and is similar to the intensity consensus.


FORECAST POSITIONS AND MAX WINDS

INIT  06/1500Z 15.2N 130.5W   65 KT  75 MPH
 12H  07/0000Z 15.7N 132.8W   70 KT  80 MPH
 24H  07/1200Z 16.4N 135.9W   75 KT  85 MPH
 36H  08/0000Z 17.0N 138.9W   75 KT  85 MPH
 48H  08/1200Z 17.7N 141.9W   70 KT  80 MPH
 72H  09/1200Z 19.0N 147.5W   60 KT  70 MPH
 96H  10/1200Z 21.0N 152.5W   55 KT  65 MPH
120H  11/1200Z 24.0N 157.5W   50 KT  60 MPH

$$
Forecaster Beven