marine weather discussion for N Pacific Ocean NWS ocean prediction center Washington DC 655 am PDT Wed Sep 2 2015
.Forecast discussion: major features/winds/seas/significant .Weather for the North Pacific N of 30n and E of 150w.
An area of low pres analyzed at 1004 mb by the 12z opc/NCEP prelim sfc analysis will remain N of the waters and move inland today and tonight...generating some scattered showers and thunderstorms across the pz5 zones. A coastal trough will strengthen today and persist through the end of the forecast period. High pressure will continue to build E through Friday and then remains nearly stationary W of the waters through Sunday night.
Models remain consistent and in good agreement. See no reason to change much with this forecast package.
Seas...models match observations well and are in good agreement. Will continue to use the enp wave model with this package.
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The curr Sat img infers conv ovr the nrn wtrs and the far srn parts but with almost no lgtng strikes. The radar has no indc of tstms cells ovr the region. There is still up to 30 percnt chnc of tstms ovr the nrn wtrs in the short term. At 06z hgh pres 1030 mb nr 43n155w has its ridge strechng se into the srn wtrs while a cld frnt that strctches frm low pres ovr Canada coast lies acrs the nrn wtrs. Inland trof strtches from srn CA to the nrn CA. The pres grdnt is still weak and Max obs winds are 15 kt. The latst ascat pass at 0545z missed the area that had gale force winds earlier. Ascat pas show only 20 kt winds ovr the NW parts and does not incdt any gale force winds just NW of the region. The obs stll hv gale force winds nr the low cntr.
Most of the enrgy is still embdd in an upplvl low pres trof just NW of the region while the rest of the trof xtndg to just W of the srn wtrs has very litle enrgy. An upprlrvl ridge lies to the W of the upplvl trof. There is still very little energy ovr the srn CA that has maintained the inland trof. Most of the erngy to the N will shift se and pass acrs the N-ern parts of the wtrs and that will allow the cld frnt acrs the nrn wtrs to persist as it slowly moves se. Xpect the pres grdnt to tighten but not enough to generate gale force winds ovr the wtrs. Winds will be elevated to just below gale force.
The glbl mdls hv continued to initalize well with the curr obs and they hv been quite cosstnt in the previous runs. The only problem is that they sligthly differ on the strength and speed of the low pres track that will pass acrs the ern parts of the nrn wtrs. Other wise these mnr diffs are meagre and so will continue with GFS. In the short term the low pres to the N ovr Canada coast will move E inland and that will allow the assoctd gale force winds to diminsh over the area to the NW of the region. The hgh pres ovr the pac will drift E at about the same strength while the inland trof will persist...and that will force the isobars btwn the two features to pack up and enhance the winds ovr the ern parts of the cntrl region. Otherwise winds shud remain below gale force even into the xtndd prd acrs the board.
.Seas...The seas are hghst ovr the NW parts of the nrn wtrs with 12 ft peak while they range btwn 7 and 10 ft elsewhere. Both nww3 mulri grid and the ecmwfwv agree well with the obsvd seas pattern and see no Ned to deviate from either mdl gdnc. For this frcst will go with nww3.
.Extratropical storm surge guidance...N/A.
.Pz5 Washington/Oregon waters... None.
.Pz6 California waters... None.
.Forecaster Sommerville/musonda. Ocean prediction center.