000
WTPZ42 KNHC 270859
TCDEP2

HURRICANE IGNACIO DISCUSSION NUMBER  10
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP122015
200 AM PDT THU AUG 27 2015

Very cold cloud tops persist near the center of Ignacio, although
the overall cloud pattern is not very symmetric and no eye is
present in conventional satellite data. However, microwave images
show an eye beneath the cirrus clouds, but not well established
in the low-level channel.  Current intensity estimates range from 75
to 90 kt, and since the cloud pattern isn't particularly well
organized, I've elected to go on the low end of the estimates with
75 kt as the initial intensity.

The initial motion estimate remains 290/11.  A west-northwestward
motion is expected to continue throughout the forecast period due to
a strong subtropical ridge to the north of Ignacio producing a deep
layer of east-southeasterly steering flow.  Models are continuing
to struggle with the strength of the ridge in the long range
period, with a variety of solutions from the normally reliable
global models.  Since the track consensus is virtually unchanged,
the NHC forecast will stay very close to the previous one and wait
for a stronger signal before making any significant modifications.

Further strengthening seems likely with Ignacio over the next couple
of days with light-to-moderate easterly shear, warm water and a
moist atmosphere.  By days 3 and 5, thermodynamic and oceanic
conditions are expected to become less favorable, with an increase
in southwesterly shear, and gradual weakening is expected to occur
during that time. The official intensity forecast is similar to the
previous advisory, and is close to the consensus model IVCN.

FORECAST POSITIONS AND MAX WINDS

INIT  27/0900Z 12.6N 138.5W   75 KT  85 MPH
 12H  27/1800Z 13.2N 139.9W   85 KT 100 MPH
 24H  28/0600Z 14.2N 141.9W   95 KT 110 MPH
 36H  28/1800Z 15.1N 143.7W  100 KT 115 MPH
 48H  29/0600Z 15.9N 145.2W  100 KT 115 MPH
 72H  30/0600Z 17.2N 147.9W   95 KT 110 MPH
 96H  31/0600Z 18.5N 150.5W   85 KT 100 MPH
120H  01/0600Z 20.0N 153.5W   75 KT  85 MPH

$$
Forecaster Blake