marine weather discussion for N Pacific Ocean NWS ocean prediction center Washington DC 1222 PM PDT sun 5 Jul 2009

.Forecast discussion: major features/winds/seas/significant .Weather for the North Pacific N of 30n and E of 150w.

At 18z the sfc analysis had a weak low pres center just S of Vancouver Island with a low pres trough extending SW from the low SW to a second low 210 nm W of Pt St George. The thermal trough was located along the California coast with a high pres ridge in the Gulf of Alaska and to the W of the California coast.

The latest sfc observations had N to NW winds 10 to 20 kt from Cape Foulweather N to Cape Flattery W of the trough. E of the trough in the coastal waters winds were out of the S 10 to 15 kt. From cape foulweaterh to pt Conception winds were variable 10 kt or less and S of pt Conception to Guadeloupe island NW 10 to 15 kt. The 18z seas state analysis had seas 5 to 8 ft from Cape Blanco N to Cape Flattery and 3 to 5 ft S of Cape Flattery to the Mexican border.

A upper trough SW of pz5 waters will move NE tonight and Mon then stall and form a close low over the N waters Tue into Fri. A shrt wave will rotate arnd the upper low through the week. At the sfc the weak low pres center W of Pt St George will move NE tonight across the Cape Lookout to Pt St George waters and inland Mon. The low pres trough move inland Mon with a weak ridge building into the area. A sfc low will develop near the Queen Charlotte islands late Mon ...then move se into the waters and stall Tue through Thu this while slowly weakening. For the pz6 waters high pres will build Tue through Fri with the thermal trough remaining in place along the CST.

For the fcst will continue to go with the GFS...hwvr the models are in good agreement. The problem of the day will be if the strongest winds will be W of pt Conception or to the NW over the E portions of pt Arena to pt Conception. The GFS over the last two day and slowly trended from SW of of pt Conception to extending the strongest winds N along the coast. By day 5 the ec and Gem push the 25 kt winds N to Pt St George and are slightly stronger with the N winds over pz5. Again will use the GFS but will scale back winds S of pt Conception to 20 kt day 5 and for pz5 will inc slightly to N 10 kt closer to the ec and Gem.

For seas will go with the wave watch model. The model is within a ft in mostly light seas across the offshore waters. The only area where seas inc are vicinity pt Conception Tue into Fri.

.Warnings/forecast confidence...Warnings are preliminary and are subject to change. Any changes will be coordinated through AWIPS 12 planet chat or by telephone.

.Pz5 Washington/Oregon waters... .Cape Flattery to Cape Lookout...none. .Cape Lookout to point St George...None.

.Pz6 California waters... .Pt St George to pt Arena...none. .Pt Arena to pt Conception...None. .Pt Conception to Guadalupe island...None.

.Forecaster oszajca. Ocean forecast branch.

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