marine weather discussion for N Pacific Ocean
NWS ocean prediction center Washington DC
625 PM PDT Thu 3 Jul 2008

Forecast discussion: major features/winds/seas/significant
weather for the North Pacific N of 30n and E of 150w.

No changes are planned for the evening update. The 18z GFS was
pretty similar to the 12z GFS run through most of the fcst
period. For the short term...will maintain the gale for the S CA
waters tonight...mainly for gusts to gale force near Point
Conception. Looking ahead...the next significant event is still
expected later sun through Tue with gales fcst for the S or
waters as well as the N CA waters. The 18z GFS has trended a bit
stronger with the high which is fcst to build W of the offshore
waters...which is more in line with the 12z ECMWF. The current
fcst has winds to 35 kt over these areas later sun into Tue
which looks reasonable for now. If 00z GFS continues to trend in
this direction...will likely increase winds to 40 kt over these
areas.
Previous discussion...

An upr lvl low pres trof extending S from upr lvl low pres
centered just W and NW of The Wash off wtrs will lift NE across
the off wtrs Fri as the next upr lvl low moves to nr 50n 140w lt
Fri. This upr lvl low will slide E toward the qn Charlotte
island ovr the wknd as upr lvl high pres builds from the SW
states W over srn and central cal off wtrs to N of Hawaii. This
upr lvl ridge will cont to build ovr the east pac during at
least the first part of next wk as upr lvl low pres dominates
the Gulf of AK.

In the near term...we will maintain marginal gales ovr NE socal
off wtrs as both the 12z NAM and 12z GFS maintain the idea of at
least freq gale force gusts ltr tdy thru much of tngt...as the
pres grad tightens between thermal low pres inland and high pres
W of the socal off wtrs. The low is expected to wkn Fri with bl
winds becoming sub-gale early. This idea continues to match up
well with the cwf from lox. Elsewhere...a wk sfc high pres ridge
will extend from NE to SW across the central and nocal off wtrs
into Sat. A cold front is still fcst to cross pz5 and nrn nocal
off wtrs Fri ngt and Sat.

Longer term...sfc high pres will build to the W of the off wtrs
lt sun...and then persist Mon and Tue. A coastal low pres trof
will intensify ltr sun and then remain strong Mon and Tue. As a
result...we still expect min gales to dvlp ovr far ern nocal off
wtrs lt sun...and to cover mainly NE nocal into se oreg off wtrs
Mon and Tue.

Models...for the most part we will remain close to the 12z
GFS... but believe that the 12z ecwmf has a good idea in having
stronger high pres W of the area Mon and Tue...thus leading to
higher confidence in the gales described abv. We will keep Max
bl winds at 35kt in the gale area for now...but note that should
the higher pressures noted by the 12z ecwmf verify then 40+kt bl
winds would become more lkly ovr the NE nocal/se oreg wtrs Mon
and especially by Tue. We will cont to monitor this idea ovr the
next few days.

Seas...for the most part we will remain close to the 12z ww3 mdl
guid for most of this period. We will cont to add a ft or two to
its guid mainly in/near the gale force wind areas thru the fcst
period.

Warnings/forecast confidence...preliminary. Any changes will be
coordinated through AWIPS 12 planet chat or by telephone:

.Pz5 Washington/Oregon waters...
.Cape Flattery to Cape Lookout...none.
.Cape Lookout to point St George...Gale se part Mon/Tue...MDT
confdc.

.Pz6 California waters...
.Pt St George to pt Arena...gale E part lt sun thru Tue...MDT
confdc.
.Pt Arena to pt Conception...None.
.Pt Conception to Guadalupe island...Gale far NE part tngt...low
to MDT confdc.

.Forecaster kosier/Mills. Ocean forecast branch.

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