marine weather discussion

NWS ocean prediction center Washington DC

800 PM EST Sat 21 Nov 2009

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

.Weather for North Atlantic ocean W of 50w from 30n to 50n.

Will likely edge up winds just S and SW of Cape Hatteras to 20

to 30 kt with this evenings nt2 update...based on this mornings

ascat pass. And have not seen any diminishing trend at buoys

NC/SC coasts over past few hrs. Any slight change to overngt

forecast will hinge on upcoming Quikscat tho. Models still

having difficulty with strength/track of cstl sfc low Mon/Tue.

18z NAM now takes weak sfc center just inland appearing close to

GFS runs of day or so ago...while 18z GFS also lacked

consistency with its previous run no longer brining initial weak

low thru new engl waters. Still leaning twrd ECMWF/Canadian

compromise which have been most exhibited most run to run

consistency of late. Canadian still appears too strong with

winds. Will leave winds below gale with this evenings

update...but possibility still exists mainly new engl waters

given strength of ridge over New Brunswick/ Canadian

Maritimes...and pres gradient even shown by latest gefs and

ECMWF ensmbl means.

Wavewatch iii looks within a ft of 00z ship/buoy obs over most

of W Atlc. Exception is near the entrance of glf of St Lawrence

where 12 ft buoy well above 8 ft advertised by wavewatch.

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...Previous discussion...

Low pres currently E of the nt2 waters will move slowly NE today

and tonight. N to NE winds up to 25 kt will continue across

portions of the srn and central nt2 waters into tonight. Strong

high pres will then build N of the nt1 waters sun. Weak low pres

is still expected to form across the srn nt2 waters Sun

night...then track NE across the offshore waters through Wed.

The latest runs of the NAM and GFS are in reasonable agreement

and continue the idea of the last couple of model runs in having

somewhat weaker winds across the offshore waters. The

Canadian...meanwhile...continues to be a strong outlier. For now

will continue with previous forecast of showing Max winds of 30

kt with this system as it moves NE. A cold front will then move

into the offshore waters by Thu.

The wavewatch model looks reasonable and will be followed fairly

closely during the forecast period. The E swell which wavewatch

iii brings into nern nt2 waters as well as Georges Bank sun

ngt/Mon appears reasonable as global models all indicating

decent E to NE fetch N of W Atlc cold front.

.Warnings/forecast confidence...Warnings are preliminary and are

subject to change. Any changes will be coordinated through AWIPS

12 planet chat or by telephone.

.Nt1 New England waters...

.Gulf of Maine...none.

.Georges Bank...None.

.S of New England...None.

.Nt2 mid Atlc waters...

.Hudson to balt cnyn...none.

.Balt cnyn to Hague line...None.

.Balt cnyn to Hatteras cnyn...None.

.Hatteras cnyn to Cape Fear...None.

.Cape Fear to 31n...None.

.Forecaster Clark/nolt. Ocean forecast branch.