marine weather discussion for N Pacific Ocean

NWS ocean prediction center Washington DC

600 am PST Mon 23 Nov 2009

.Forecast discussion: major features/winds/seas/significant

.Weather for the North Pacific N of 30n and E of 150w.

Latest sfc analysis from NCEP/opc places frontal boundary just

to the W of the pz5 waters...and not surprisingly out ahead of

the boundary is where the strongest winds at the sfc are

currently located across the ofshr zns. The front is expected to

push towards the WA/OR border today and stall...then lift back N

overnight as a warm front as a very large and intense hurcn

force low lifts NE into the goa tmrw. Another round of marginal

gales are expected again Tue into Wed as its associated cold

front slowly pushes eward.

Overall do not plan on making any changes to the forecast or

warning headlines that are already in place in particular for

the time frame Wed and beyond. Models are still all over the map

regarding possible developing low for the central waters on

Thu...with the latest run of the 06z GFS trending

stronger/further to the S. With continued lack of support and

agreement from ensembles...gefs mean...and other glbl solutions

will still hold off on placing gales into the forecast for now.

Across the ofshr zns forecast seas are generally within a foot

or two of obs...however just N of the area around the Queen

Charlotte Sound/hecate Strait vicinity ww3/enp values are

anywhere from 5 to 10 ft too low.

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Previous discussion:

06z NCEP prelim surface analysis shows high pres ridging across

the offshore waters while a warm front...associated with low

pres in the NW gulfak...is located about 150 nm W of the pz5

waters. Qscat passes from 0224z and 0405z indicated winds under

25 kt over the offshore waters W/the exception of the far NW WA

waters where 30 kt winds were present.

Warm front pushes thru the pz5 waters early today followed by a

cold front with continued model support for gales ahead of the

cold front. Coverage of gales in the WA waters remains

widespread while in the or waters will be limited to the nrn

portions. Next frontal system approaches late Tue...crossing the

pz5/6 waters Wed into Thu. Here also 00z models continue to

support gales ahead of the front as it moves thru the pz5 waters

Wed.

00z GFS/ECMWF/UKMET develop low pres along the front early Thu

as it begins to push out of the pz5 waters...while moving into

the central N CA waters. However differences arise W/each model

as to the low location early thurs W/the 00z UKMET placing the

low near the WA/OR border ...the 00z ECMWF just W of the or

waters and the 00z GFS in the wrn nrn CA waters. While the other

globals dont develop the low along the front they do have a

similar placement of the front when compared to all but the 00z

ECMWF. As the low/frontal structure moves inland late thurs

winds increase W/the 00z GFS suggesting NW-ly gales developing

in the or...N and central CA waters respectively. However given

the current differences noted between the models in relation to

potential low pres development along the front will not intro

gales at this time. Will allow 30 kt Max winds to continue Thu

in the pz5 waters as stated in the previous forecast while

bumping winds in the N and central CA waters up 5 kt to 30 as

well. By day 5 high pres ridge builds over the area.

Seas...00z ww3 was within 1-2 ft of 00z ship/buoy obs with its

6hr 06z forecast continue the same trend. Will remain below ww3

Thu given I plan to remain under GFS winds...otherwise will

generally follow ww3 values for this forecast package.

.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...gale today...hi confdc. Gale

Tue ngt into Wed...MDT confdc.

.Cape Lookout to point St George...Gale today...MDT to hi

confdc. Gale Tue ngt into Wed...low to MDT confdc.

.Pz6 California waters...

.Pt St George to pt Arena...none.

.Pt Arena to pt Conception...None.

.Pt Conception to Guadalupe island...None.

.Forecaster Collins/Holley. Ocean forecast branch.