000
WTPZ41 KNHC 302037
TCDEP1

HURRICANE ANDRES DISCUSSION NUMBER  11
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP012015
200 PM PDT SAT MAY 30 2015

Andres' cloud pattern has not changed much during the last several
hours.  The eye of the hurricane remains evident in visible and
infrared satellite images, but it has been occasionally obscured by
high-level clouds.  Recent microwave data show that the western side
of the eyewall has eroded slightly, which is likely the result of
northwesterly shear and drier air that is wrapping into that side of
the circulation.  The Dvorak classifications from TAFB, SAB, and the
UW-CIMSS ADT are all 5.0/90 kt, and accordingly, the initial wind
speed is held at that value.

Andres continues on a northwestward track at about 6 kt toward a
weakness in the subtropical ridge.  The models are in agreement
that the hurricane should turn west-northwestward tonight or early
Sunday when the ridge builds to the north of the cyclone. The 12Z
GFS solution has changed considerably from the previous cycle, and
now shows Andres stalling and then moving eastward in the 96-120
hour time frame in response to a mid- to upper-level trough.  That
model is considered an outlier as it is likely keeping Andres too
deep over cool waters.  The official track forecast is a little to
the north and slightly slower than the previous one after 72 hours.

The hurricane is forecast to maintain its strength for about a day
while it remains over warm water and in an environment of
decreasing shear.  Steady weakening is anticipated beyond that
time, however, when Andres moves over progressively cooler water
and into a much more stable air mass.  The official intensity
forecast is basically an update of the previous one and is in good
agreement with the intensity model consensus.

The 34-kt and 50-kt wind radii were expanded on the east side of
the circulation based on a 1650 UTC ASCAT-B pass. The 12-ft sea
radii were also expanded based on a recent altimeter pass that
showed sea heights as high as 28 ft.


FORECAST POSITIONS AND MAX WINDS

INIT  30/2100Z 14.8N 116.3W   90 KT 105 MPH
 12H  31/0600Z 15.4N 117.4W   90 KT 105 MPH
 24H  31/1800Z 15.9N 118.6W   85 KT 100 MPH
 36H  01/0600Z 16.3N 119.8W   75 KT  85 MPH
 48H  01/1800Z 16.9N 121.2W   65 KT  75 MPH
 72H  02/1800Z 18.5N 124.2W   55 KT  65 MPH
 96H  03/1800Z 19.5N 127.3W   40 KT  45 MPH
120H  04/1800Z 19.5N 129.0W   30 KT  35 MPH

$$
Forecaster Cangialosi