marine weather discussion for N Pacific Ocean NWS ocean prediction center Washington DC 146 am PDT Thu Oct 18 2018
.Forecast discussion...Major features/winds/seas/significant .Weather for the North Pacific N of 30n and E of 150w.
The ascat passes from 04-06z show mainly light winds across the offshore waters. While a weak cold front approaches the NW Washington waters. Maximum seas as indicated by observations is near 9 ft. The overall forecast pattern across the eastern Pacific during the upcoming week will remain very stable as a high pressure ridge remains anchored just W of the waters initially, then slowly building NE across much of the nt1 waters, while further S a weak low pressure trough continues along the California coast. The resulting gradient will produce a relatively weak N-NW flow across much of the waters. As the ridge builds into the nt1 waters the winds will gradually shift to SW across the NW portion as a cold front slowly approaches from the W. The 00z global models are all in very good agreement through day 5, then begin to diverge somewhat with the passage of a cold front. All of the models are indicating a cold front, although the GFS is the strongest, showing winds to 45 kt in advance of the front. The GFS has been very consistent the past several runs and will continue to be my model of choice for this package. I will populate the wind grids using the 00z GFS through 18z Mon, then use the official grids from 21z Mon T through 12z Tue in order to keep gale conditions N of the offshore waters. If the trend continues to indicate gales with the front in later runs the addition of gale warnings might be needed at a later date. I will finish the week using the ECMWF.
Seas...both the enp and wam were initialized well and matched up with their corresponding wind forecast reasonably through the period. I will populate the wave grids using the enp through 18z Mon, transition to the official grids through 12z Tue before finish by using the wam.
.Extratropical storm surge guidance...N/A.
.Pz5 Washington/Oregon waters... None.
.Pz6 California waters... None.
.Forecaster Shaw. Ocean prediction center.