ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM

HURRICANE BLANCA DISCUSSION NUMBER  15
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP022015
400 AM CDT THU JUN 04 2015

The small eye of Blanca has become less distinct in infrared
satellite images since yesterday afternoon.  Subjective and
objective Dvorak T-numbers have subsequently decreased from their
peak, so the initial intensity has been lowered to 110 kt.  It is
not clear whether the slight decrease in wind speed is a result of
an eyewall replacement cycle, drier air wrapping into the
circulation, or upwelling of cooler waters beneath the nearly
stationary hurricane.  In any case, as the cyclone begins moving
northwestward, low vertical wind shear and warmer water, along the
forecast path of Blanca, favor strengthening during the next day or
so.  The new NHC intensity forecast is close to the SHIPS guidance,
but shows a slightly lower peak intensity than the previous few
advisories.  After 48 hours, increasing shear and cool waters should
induce weakening.  A faster rate of weakening is expected after 72
hours, when the hurricane is forecast to move over SSTs below
26 deg C and into a drier and more stable air mass.

Blanca has remained nearly stationary during the past few hours.
The model guidance is in good agreement that the hurricane will
begin to move northwestward today while a mid-level ridge builds
over northern Mexico.  Blanca should move northwestward to north-
northwestward at a faster forward speed during the next few days
between the aforementioned ridge and a mid-level trough extending
southwestward from southern California.  The track guidance is
tightly clustered, but there are still significant differences in
the forward speed of the hurricane.  As a result, the NHC track
remains close to the model consensus, between the faster GFS, and
the slower ECMWF model.


FORECAST POSITIONS AND MAX WINDS

INIT  04/0900Z 11.9N 104.9W  110 KT 125 MPH
 12H  04/1800Z 12.6N 105.6W  115 KT 130 MPH
 24H  05/0600Z 13.9N 106.7W  120 KT 140 MPH
 36H  05/1800Z 15.2N 107.9W  125 KT 145 MPH
 48H  06/0600Z 16.7N 109.1W  120 KT 140 MPH
 72H  07/0600Z 19.3N 110.5W   90 KT 105 MPH
 96H  08/0600Z 22.5N 111.5W   50 KT  60 MPH
120H  09/0600Z 25.0N 113.0W   30 KT  35 MPH

$$
Forecaster Brown

NNNN