marine weather discussion for N Pacific Ocean NWS ocean prediction center Washington DC 806 am PDT Thu Oct 19 2017
.Forecast discussion...Major features/winds/seas/significant .Weather for the North Pacific N of 30n and E of 150w.
Forecast continues on track with previous forecast. A few minor adjustments to the seas will be made to better match observations, but overall, do not plan to make many changes.
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The ascat pass from 06z indicates gale conditions across the NW portion of the Washington and Oregon waters, with a small area of gales in advance of the cold front along the Oregon coast. A ridge axis is shown extending NE to SW across the central California waters. Satellite pictures show a strong area of low pressure moving into British Columbia. A large area of swell will continue to move into the waters today. An altimeter pass from 03z indicates seas near 30 ft just W of the pz5 waters.
The 00z ECMWF is late coming into GFS, and has just started ingesting. The 00z GFS is very consistent with the prior run, and relatively close to the UKMET. The very progressive pattern N of 40n will continue over the next 4 or 5 days until a ridge axis builds northward late Sunday. Once the current cold front weakens across the California waters a ridge will build E into the area and remain for much of the forecast period. The driving force over the California waters beginning Friday will the ridge/trough combination, typical along the California coast. The highest winds will occur along the inner offshore waters and coastal zones across the central and Southern California waters. An area of gales will likely occur for a time in the vicinity of The Channel islands. Given the consistency shown by the GFS during the past couple of days I will continue to populate the wind grids using that model throughout the forecast period, with small edits as needed.
Seas...for the most part the enp is doing OK across the region, generally initialized within a couple feet of the observations in areas of maximum waves. I will likely do a 50/50 blend of the enp and wam when populating the wave grids, depending if the 00z ECMWF comes into gfe in time.
.Extratropical storm surge guidance...N/A.
.Pz5 Washington/Oregon waters... .pzz800...inner waters from Cape Flattery to Cape Shoalwater... gale possible Saturday. .Pzz805...Inner waters from Cape Shoalwater to Cape Lookout... gale Friday night. .Pzz905...Outer waters from Cape Shoalwater to Cape Lookout... gale possible Saturday. .Pzz810...Inner waters from Cape Lookout to Florence or... gale Friday night. Gale possible Sunday. .Pzz910...Outer waters from Cape Lookout to Florence or... gale possible Saturday. .Pzz815...Inner waters from Florence or to point St. George... gale Friday night. .Pzz915...Outer waters from Florence or to point St. George... gale Friday night.
.Pz6 California waters... .pzz840...inner waters from Santa Cruz Island, CA to San Clemente Island, CA... gale Friday night.
.Forecaster Sommerville/Shaw. Ocean prediction center.