marine weather discussion for N Pacific Ocean NWS ocean prediction center Washington DC 608 PM PST Sat Feb 23 2019
.Forecast discussion...Major features/winds/seas/significant .Weather for the North Pacific N of 30n and E of 150w.
Low pressure just north of the Washington offhshore waters will move southeast tonight and Sunday while slowly weakening. Meanwhile, low pressure is still expected to move into the northern pz6 waters Sunday night and then continue inland Monday. Minimal gales are still expected in association with this low. Another low will then move into the northern and central pz6 waters by Tuesday night. Minimal gales are also possible with this low, but for now will keep the strongest winds across the offshore waters at 30 knots and see what the later model runs show. Farther south, mainly light winds are expected across the southern pz6 waters tonight into Thursday. 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.
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An ascat pass around 1809z showed winds over the waters generally 10 to 20 kt. The 18z surface chart continues to show a stationary front over the southern pz5 waters and high pressure over the pz6 waters. These observations match well with the global model solutions. The models are in good agreement through Tuesday night, with some minor differences. We prefer the intensity and areal coverage of the expected gales with a low moving along the front across the central waters Sunday night through Monday given by the ECMWF, so will begin the forecast with it.
By Wednesday, the models begin to show some larger differences. The GFS, UKMET, and Canadian models are in the best agreement, with the ECMWF diverging a bit from them. We will transition to the GFS by 12z Wednesday. The GFS does introduce small areas of gales very late in the period, but will elect to cap the winds here as gales are not expected to be widespread or persistent.
.Seas...The wave models have initialized well, so we plan on following the same reasoning as the wind grids, using the wam through 12z Wednesday, then the ww3 through the end of the period.
.Extratropical storm surge guidance...N/A
.Pz5 Washington/Oregon waters... .pzz815...inner waters from Florence or to point St. George... gale Monday.
.Pz6 California waters... .pzz820...inner waters from point St. George to Point Arena... gale Sunday night into Monday. .Pzz920...Outer waters from point St. George to Point Arena... gale Sunday night. .Pzz925...Outer waters from Point Arena to Pigeon Point... gale Monday.
.Forecaster nolt/Sommerville. Ocean prediction center.