262 
WTPZ41 KNHC 031432
TCDEP1

Hurricane Sergio Discussion Number  17
NWS National Hurricane Center Miami FL       EP212018
800 AM PDT Wed Oct 03 2018

Sergio has intensified this morning, with the eye becoming better
defined while embedded in very cold cloud tops.  The upper-level
outflow is restricted to the northeast of the hurricane, but strong
over the southern part of the circulation.  Using a blend of
objective and subjective Dvorak estimates, the advisory intensity
estimate is 110 kt.  Sergio will remain over warm waters of nearly
29 deg C,  with moderate shear and a humid mid-level air mass for
the next day or so.  Thus, some additional strengthening is forecast
in the short term.  In a couple of days, slightly cooler waters and
some entrainment of dry air is likely to cause a gradual weakening
trend to begin.  The NHC forecast is at the high end of the
intensity model guidance, and shows Sergio remaining a hurricane
throughout the entire forecast period.

The hurricane has turned toward the northwest, and is now moving at
about 305/9 kt.  This turn is probably being caused by a weakness in
the mid-level ridge associated with a trough nearing southern
California.  As the trough moves away from the area, the global
models predict that a ridge will rebuild to the north of Sergio in
a couple of days.  This should result in a turn toward the
west-northwest and west at 48 hours and beyond.  The official track
forecast is close to the simple and corrected dynamical model
consensus predictions.

FORECAST POSITIONS AND MAX WINDS

INIT  03/1500Z 12.9N 117.3W  110 KT 125 MPH
 12H  04/0000Z 13.6N 118.3W  120 KT 140 MPH
 24H  04/1200Z 14.7N 119.6W  120 KT 140 MPH
 36H  05/0000Z 15.6N 120.9W  120 KT 140 MPH
 48H  05/1200Z 16.2N 122.0W  110 KT 125 MPH
 72H  06/1200Z 16.3N 124.5W   95 KT 110 MPH
 96H  07/1200Z 16.3N 127.2W   90 KT 105 MPH
120H  08/1200Z 17.0N 130.0W   85 KT 100 MPH

$$
Forecaster Pasch