marine weather discussion for N Pacific Ocean NWS ocean prediction center Washington DC 1258 PM PDT Thu Jul 31 2014
.Forecast discussion: major features/winds/seas/significant .Weather for the North Pacific N of 30n and E of 150w.
Summary...the late am hi res ascat-b pass indicated an area of 25 kt N winds extending from coastal SW Oregon S to off the nocal coast with winds of 20 kt or less elsewhere ovr the off wtrs. This is in gud agreement with the ongoing opc fcst. Overall... little change appears needed to the prev fcst for the aftn fcst package. The region will remain located between a high pres ridge W of the wtrs...and a low pres trof extending from the SW oreg coast S and se along the calif coast for the next few days. The pres grad between the high and the trof is expected to strengthen somewhat tngt into sun ngt...and then weaken Mon and Mon ngt as a wk cold front moves se ovr pz5 wtrs. The front will lkly dsipt Tue and Tue ngt with high pres building W of the wtrs allowing for winds to increase slightly again at that time.
Weather...we will add a mention of iso tstms to the off wtrs adj the sew cwf for Fri as mdl guid shows a 500 mb vort Max sliding NE ovr these wtrs Fri. Also we will add patchy fog to off zones adj to the calif coastal wtrs lt tngt and again at times into Sat to match nearby cwf.
Models...the 12z mdls are in pretty gud agreement thru early next wk. We will once again stay close to the 12z GFS and the GFS 30m winds for the off wtrs thru sun. For sun ngt thru Tue ngt we will switch to using the 12z ECMWF...and boost the ECMWF winds by 15 percent or so...mainly for wtrs off the SW oreg and nocal coast where we expect the pres grad to remain the strongest early next wk. This will keep Max winds at 30 kt for these wtrs for most of the fcst package. There is a slight risk for gales ovr these wtrs ovr the next few days...and again by Tue or so of next wk. At this time chances are too low to add any gales to the off fcst.
.Seas...The 12z enp version of the WV watch iii appears to be initializing well ovr the off wtrs per the latest obs. We will stay close to the enp ww3 mdl guid thru sun...and then switch to the ECMWF wam WV guid for sun ngt thru Tue ngt. Overall...no major changes for the aftn package from the prev few opc fcsts.
.Extratropical storm surge guidance...Na
.Pz5 Washington/Oregon waters... None.
.Pz6 California waters... None.
.Forecaster Mills. Ocean prediction center.