WTPZ42 KNHC 081436
Hurricane John Discussion Number 12
NWS National Hurricane Center Miami FL EP122018
900 AM MDT Wed Aug 08 2018
The satellite presentation of John has degraded over the past 12
hours or so, with the eye no longer present in conventional
satellite data. The CDO has also become considerably less
symmetric than noted yesterday. Satellite intensity estimates
range from 65 to 77 kt, and the initial intensity has been
lowered to 75 kt for this advisory. John will be moving over
cooler waters within the next 6-12 hours and into a more stable
atmosphere, which should cause gradual weakening through tonight.
By Thursday, John will be moving over much colder SSTs and a more
rapid rate of filling is expected by that time. John is predicted
to become a remnant low in 2 to 3 days as it reaches SSTs of around
The hurricane is moving northwestward or 320/10 kt. John should
continue moving northwestward while it remains a vertically deep
cyclone, but once it weakens and becomes a more shallow system it
is expected to turn west-northwestward in the low-level trade
wind flow. The dynamical model guidance remains in excellent
agreement and little change was required to the previous NHC
Although the center of John is forecast to remain well offshore of
the Baja California Peninsula, a surge of moisture around John's
outer circulation is expected to bring some locally heavy rainfall
to portions of Baja California Sur during the next couple of days.
Therefore, interests in the southern portion of the Baja California
Peninsula should monitor the progress of John.
John is also producing large swells that are already affecting
portions of the coast of the southern Baja California peninsula.
These swells are predicted to spread northward along the west coast
of the peninsula today and reach portions of the coast of southern
California by late Thursday. These swells are likely to cause
life-threatening surf and rip current conditions. Please consult
products from your local weather office.
FORECAST POSITIONS AND MAX WINDS
INIT 08/1500Z 20.7N 112.3W 75 KT 85 MPH
12H 09/0000Z 22.0N 113.7W 65 KT 75 MPH
24H 09/1200Z 23.5N 115.9W 60 KT 70 MPH
36H 10/0000Z 24.9N 118.1W 50 KT 60 MPH
48H 10/1200Z 25.9N 120.2W 40 KT 45 MPH
72H 11/1200Z 26.9N 123.9W 30 KT 35 MPH...POST-TROP/REMNT LOW
96H 12/1200Z 27.0N 126.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 13/1200Z 27.5N 126.8W 15 KT 15 MPH...POST-TROP/REMNT LOW
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