969 
WTPZ42 KNHC 070831
TCDEP2

Hurricane John Discussion Number   7
NWS National Hurricane Center Miami FL       EP122018
300 AM MDT Tue Aug 07 2018

Satellite images indicate that John has resumed its intensification
trend, with a ragged eye showing up in the night-visible and other
channels.  Dvorak estimates are between 70-90 kt, so 80 kt is used
as the initial wind speed.  John has another day or so to intensify
in a low-shear, warm-water environment before it rapidly crosses
into cooler waters.  The hurricane has been intensifying at a rate
of about 30 kt/24 hours, so this trend was heavily weighted in the
latest forecast given the continuation of the conducive environment.
All of the guidance show a pretty steep drop in intensity as the
hurricane quickly enters cool waters, with rapid weakening likely.
The latest forecast is close to the previous one, but shows John
becoming post-tropical by day 4 when it will be over 21C waters.

John continues to move northwestward, now at about 8 kt.  The
hurricane should move in that general direction but faster over the
next 3 days under the influence of a strengthening subtropical
ridge.  As John weakens, the cyclone is forecast to turn westward,
steered more by the low-level ridge.  Guidance remains tightly
clustered and no significant change was made to the previous
forecast track.

The dangerous core of John is forecast to remain well offshore of
the Baja California Peninsula.  However, an eastward shift of the
forecast track or an unexpected increase in the size of the outer
wind field of the hurricane could bring tropical-storm-force winds
to portions of the west coast of the peninsula. Therefore, interests
in the southern portion of the Baja California Peninsula should
monitor the progress of this hurricane.

FORECAST POSITIONS AND MAX WINDS

INIT  07/0900Z 17.3N 109.1W   80 KT  90 MPH
 12H  07/1800Z 18.2N 109.9W   90 KT 105 MPH
 24H  08/0600Z 19.7N 111.2W  105 KT 120 MPH
 36H  08/1800Z 21.3N 112.8W  105 KT 120 MPH
 48H  09/0600Z 22.9N 114.9W   90 KT 105 MPH
 72H  10/0600Z 25.8N 119.3W   55 KT  65 MPH
 96H  11/0600Z 27.2N 123.1W   40 KT  45 MPH...POST-TROPICAL
120H  12/0600Z 27.0N 126.5W   30 KT  35 MPH...POST-TROP/REMNT LOW

$$
Forecaster Blake