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AGPN40 KWNM 261444

Marine Weather Discussion for N Pacific Ocean
NWS Ocean Prediction Center Washington DC
744 AM PDT Sun Mar 26 2017

.FORECAST DISCUSSION...Major features/winds/seas/significant
.weather for the North Pacific N of 30N and E of 150W.

The satellite images show most of the high clouds now moving
inland east of the region with the lightning density map showing
no lightning strikes across the region. The SREF model has PROB 0
for severe TSTMS over the region and that remains the same
through the short term. The latest observations show highest
winds in the gale force range over the far north waters. Winds
are generally from the south over the eastern parts of the north
waters and W to SW over the wester portion. Otherwise winds are W
to NW over the central and southern waters. At 1200Z the NCEP
map has low pressure 983 MB near 50N140W hast its occluded front
through the northern waters then continues as a warm front over
the eastern parts of the central region while a cold front
stretches southwest across north California waters. High pressure
1028 MB west of the southern waters extends its ridge east into
the southern waters and that has maintained a slack pressure
gradient south of 35N.

The largest seas are over the northern waters with peak at 12
ft. Seas are relatively large elsewhere ranging between 7 and 9
ft with a secondary peak at 10 ft over the far southern waters.
The wave models NWW3 and ECMWFWAVE fit very well with the
observed seas pattern and both models  have been quite
consistent in the previous runs and are also in good agreement at
least through the short term and so will not deviate from the
NWW3 solution for the seas.

The models GFS/CMC/NOGAPS/UKMEHR/ECMWFHR/NAM have all generally
initialized well with the 12Z surface observations especially
with the pressure field. There are some differences on the wind
speed over the northern waters up to 15 kt. GFS seem to be the
most aggressive while UKMETHR and ECMWFHR are on the low side.
Otherwise the models agree on gales over the far north waters.
Will continue with GFS. In the short term, low pressure to the
west of the north waters will move east passing just north of the
region while the associated occluded and warm fronts move east
and cold front dipping southeast.


At 06z a warm front was over the southwest PZ5 waters while a
1016 mb low was over the southeast PZ6 waters. A high pressure
ridge was across the rest of the PZ5 and PZ6 waters. Latest ASCAT
high resolution pass indicates 20-30 kt winds over the outer PZ5
waters with 20 kt winds in the inner waters. 10-20 kt winds were
noted over northeast PZ6 waters and southern PZ6 waters east of

Populated grids with the 00z GFS through Mon 12z which didn`t
result in significant changes to the warning headlines in
currently place. Beyond that left the existing grids from
yesterday afternoon`s forecast in place. Anticipate gales ahead
of the front to dissipate by late Sun morning as the front begins
to move east of the waters. In terms of additional warning
headlines...chance of brief period fo gales Mon night into early
Tue as a low pressure trough briefly strengthens along the CA
coast before weakening. Expecting yet another round of
gales...this time in the southern PZ6 waters by day 5 in the
northwest flow between inland troughing and an east Pacific high.

.SEAS...Populated grids through Mon 12z with 00z NWW3 then used
existing grids in place afterwards through the end of day 5.



.PZ5 Washington/Oregon Waters...
.PZZ800...Inner Waters from Cape Flattery to Cape Shoalwater...
     Gale today.
.PZZ900...Outer Waters from Cape Flattery to Cape Shoalwater...
     Gale today.
.PZZ805...Inner Waters from Cape Shoalwater to Cape Lookout...
     Gale today.
.PZZ810...Inner Waters from Cape Lookout to Florence OR...
     Gale today.
.PZZ815...Inner Waters from Florence OR to Point St. George...
     Gale today.

.PZ6 California Waters...
.PZZ825...Inner Waters from Point Arena to Pigeon Point...
     Gale Possible Thursday night.
.PZZ830...Inner Waters from Pigeon Point to Point Piedras Blancas...
     Gale Possible Thursday night.
.PZZ835...Inner Waters from Point Piedras Blancas to Santa Cruz Island, CA...
     Gale Monday night.
     Gale Possible Thursday night.
.PZZ840...Inner Waters from Santa Cruz Island, CA to San Clemente Island, CA...
     Gale Monday into Monday night.
     Gale Possible Tuesday.
     Gale Possible Thursday night.
.PZZ945...Outer Waters from 120W to San Clemente Island, CA...
     Gale Monday night.


.Forecaster Musonda/Holley. Ocean Prediction Center. is the U.S. government's official web portal to all federal, state and local government web resources and services.