Marine Interpretation Message
Issued by NWS
AGPN40 KWNM 251506
Marine Weather Discussion for N Pacific Ocean
NWS Ocean Prediction Center Washington DC
706 AM PST Sat Feb 25 2017
.FORECAST DISCUSSION...Major features/winds/seas/significant
.weather for the North Pacific N of 30N and E of 150W.
At this time I dont plan on making any changes to the grids or
associated text forecast. The biggest challenge will come
tommorrow. There is a decent chance of minimal gales occuring
associated with a short wave moving southward along the
Washington and Oregon coast. I will revisit that possibility
again after the 12z model cycle completes.
The 06z surface analysis indicated low pressure over the Oregon
offshore waters, with a trough extending southwest from the low.
A high pressure ridge extended across the central and southern
California waters. An ascat pass from late Friday evening
indicated an area of 20 kt winds over the western portion of
Washington and Oregon waters, as well as the central California
coastal waters. Otherwise, winds ranged from 5 to 15 kt.
The 00z models are in very good agreement during the upcoming
forecast period. The low pressure mentioned above will move south
today across the nothern California waters before turning
southeast over the central California waters tonight. Will
continue to use the official grids during this period and will
also maintain the marginal gales for the southern portion of
central California waters tonight. Expect these to be short lived
and decrease by Sunday morning as the low moves inland and
dissipates. The models are also all very close with low pressure
which will form in the vicinity of Queen Charlottes later today,
then move southeast passing across the Washington coastal waters
later tonight and early Sunday. Plan on using the first sigma
level winds to account for stronger winds in unstable areas
Sunday and Sunday night. Even using these winds keeps speeds just
below gale over the Washington and Oregon waters. Will then use
the GFS 10m winds beginning 12z Monday through remainder of
period. A high pressure ridge will slowly build across the area
later Monday through Wednesday night while trough forms along
California coast and persists through the period. In summary,
will use official grids through 12z Sunday, first sigma level
from 15z Sunday through 12z Monday, then GFS 10m winds.
.SEAS...The 06z sea state analysis indicated that observed seas
matched up well with the MWW3 and ECMWF WAM. Similar to wind
grids, will use official grids through Sunday morning, then MWW3
for remainder of period.
.EXTRATROPICAL STORM SURGE GUIDANCE...N/A.
.PZ5 Washington/Oregon Waters...
.PZ6 California Waters...
.Forecaster Shaw/Kosier. Ocean Prediction Center.