ZCZC MIATCDEP5 ALL
TTAA00 KNHC DDHHMM

HURRICANE DARBY DISCUSSION NUMBER  15
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP052016
200 AM PDT FRI JUL 15 2016

Darby has changed little in organization during the past several
hours, with satellite imagery showing a ragged 25 n mi wide eye
embedded in the central dense overcast.  Subjective satellite
intensity estimates are 90 kt from TAFB and 77 kt from SAB, while
various objective estimates from CIMSS are in the 75-80 kt range.
Based on these data, the initial intensity remains at 80 kt.

The initial motion is 280/10.  There is no change to the forecast
philosophy from the previous advisory, and there are no important
changes to the forecast track.  The model guidance is in excellent
agreement that Darby will move generally west-northwestward for the
next 36-48 hours, followed by a more westward motion after, as the
subtropical ridge to the north of the hurricane builds slightly
southward and westward. The new NHC track remains just a little to
the south of the center of the guidance envelope.

Some strengthening is possible during the next 12 hours while the
center of Darby remains over relatively warm water.  After that,
the forecast track takes the cyclone over decreasing sea surface
temperatures through 72-96 hours, possibly as cold as 24C.   This
should cause significant weakening despite an otherwise favorable
shear environment.  It is possible that Darby could weaken more than
currently forecast, as it appears that the sea surface temperatures
near 130W are colder than those used by the SHIPS model.  After 96
hours, the forecast track takes the cyclone over sea surface
temperatures near 26C at the same time that it encounters a drier
air mass.  Thus, slow weakening is expected to continue.  The new
intensity forecast is slightly weaker than the previous forecast
and is in best agreement with the IVCN intensity consensus.


FORECAST POSITIONS AND MAX WINDS

INIT  15/0900Z 16.1N 120.0W   80 KT  90 MPH
 12H  15/1800Z 16.5N 121.5W   85 KT 100 MPH
 24H  16/0600Z 17.2N 123.5W   80 KT  90 MPH
 36H  16/1800Z 17.6N 125.3W   75 KT  85 MPH
 48H  17/0600Z 17.9N 127.0W   70 KT  80 MPH
 72H  18/0600Z 18.5N 131.0W   60 KT  70 MPH
 96H  19/0600Z 19.0N 135.5W   50 KT  60 MPH
120H  20/0600Z 19.0N 140.5W   45 KT  50 MPH

$$
Forecaster Beven

NNNN