Marine Interpretation Message
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000
AGPN40 KWNM 110207
MIMPAC

Marine Weather Discussion for N Pacific Ocean
NWS Ocean Prediction Center Washington DC
607 PM PST Sun Dec 10 2017

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

The latest model guidance indicates that a cold front currently
approaching the pz5 and northern pz6 waters will move across the
northern pz5 waters by late Monday and Monday night. Still expect
minimal gales across the far northwest Washington offshore waters
by Monday night ahead of the front. Another weakening cold front
will then approach the pz5 waters by Wednesday night, then move
into the offshore waters by Thursday and Thursday night. A
stronger cold front will then cross the pz5 waters Friday with
winds up to 30 knots behind the front. Farther south, mainly
light winds will continue across most of the southern and central
pz6 waters through Tuesday night, then begin to strengthen a
bit. Northerly winds will then increase to near gale force by
late Friday as strong high pressure builds west of the offshore
waters. For wind grids will continue to use the current grids
throughout the forecast period. Current warnings look reasonable
and few changes should be needed on the next offshore waters
forecast.

For wave height grids will also continue to use the current
grids throughout the forecast period.

Extratropical storm surge guidance...n/a.

-----------------------------------------------------------------
PREVIOUS DISCUSSION...

There was an ASCATB pass at 1745Z with a swath along the ern
edge and over ern areas of the offshore where data was available
strongest winds were to 15 kt along the ern edges of the WA/OR
waters, otherwise winds were light and variable at 5 to 10 kt
over the CA waters with a surface ridge over this region.

At 18Z a strong cold front was W of the offshore waters and
moving slowly E towards the region. Models are similar with the
front gradually weakening while moving E towards the area.
Models also show low press developing and forming along the front
later tonight and W of the nrn CA and OR waters. The low pres
moves N along the front W or near the WA/OR waters Mon. Models
show upper dynamics are strong, although the 12Z GFS is now
weaker than the 06Z guidance and subgale. The UKMET/GEM/ECMWF
are showing a stronger low with the UKMET deeper than other
guidance and slightly deeper than 00Z guidance. Plan to favor the
12Z ECMWF and continue to have winds increasing to 40 kt by late
Mon into Mon night over the outer areas of the nwrn WA waters.
For Tue through Thu another strong cold front front approaches
and does not move into the offshore until Thu. The ECMWF is
stronger with another cold front moving into the offshore waters
Fri and prefer the GFS which is not as strong with an associated
low pres that moves NE and passes N of the WA/OR waters. Will
likely use the GFS at this time and have winds to 30 kt over the
WA/OR waters. Elsewhere along the CA coast later in the week a
coastal trof develops. The GFS/UKMET are stronger with the area
of high pres that approaches the northern CA during this period
while the GEM/ECMWF are weaker. Will have winds to 30 kt and may
adjust somewhat.

Seas...Will use the ECMWF wam through 12Z Tue since prefer its
solution, although it is somewhat higher than earlier with seas.
Will likely adjust seas down by several feet over the NW WA
waters late Mon and Mon night. From 12Z Tue into 00Z Fri will use
a 50/50 blend of the models with few differences, then for Fri
into Fri night will use the WWIII ENP.

Extratropical storm surge guidance...n/a.


.WARNINGS...Preliminary.

.PZ5 Washington/Oregon Waters...
.PZZ900...Outer Waters from Cape Flattery to Cape Shoalwater...
     Gale Monday night.

.PZ6 California Waters...
     None.

$$

.Forecaster Nolt/Rowland. Ocean Prediction Center.



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