marine weather discussion
NWS ocean prediction center Washington DC
315 am EDT Mon 15 Mar 2010

.Forecast discussion: major features/winds/seas/significant
.Weather for North Atlantic ocean W of 50w from 30n to 50n.

At 15/0600z...vert stacked low pres cntr is just S of S of New
England zone with the ocln extndg acrs nt1 wtrs FM Cape Cod acrs
Georges Bank and nr term acting as main focus of Ely gales with
high pres ridging to the N ovr nrn New England and cndn mrtms.
Lrg contrast in wnds N of fnt versus S of fnt as seen in evening
ascat pass...33 to 42 kt N of fnt and 10 to 20 kt just to the S
in high res data. Due to low bias of ascat this apprs to sprt
presently fcst stg gales in glf of Maine and nrn Georges Bank.
To the S in W to NW flow ascat wnds 20 to 25 kt with some 30 kt
in high res data S of hat cnyn highest in the S...appr to sprt
present fcst.

Short term...the vert stacked low pres cntrd just S of S of New
England wtrs will drft se with upr low aft remaining nrly stnry
overnight...while h5 shrtwvs rotating arnd upr cntr frm new lows
to E. Main low conts to move se across the nrn nt2 wtrs today
and then mov E of the nt2 wtrs late Mon night and Tue. The low
will then reform twd new cntrs to the E while the NE to N gales
on the back side shift S. Will cont to have highest confdc in
gales in nt1 and nrn nt2 wtrs N and E of balt cnyn but S to Cape
Fear expecting only mod confdc in mrgl gales with GFS 30m wnds
giving up to 35 kt in caa. Meanwhile...high pres ridge will
build se on Tue before it moves E over the nrn half of the
region. The ridge will then weaken Wed as a cold frnt moves se
across the nrn wtrs. The pres grdnt will remain intact thru Tue
and so will keep wrngs in wtrs...longest in the outer wtrs of
balt cnyn to Hague ln.

Models...mdls are in gud agrmnt on most of the mjr synop
features. I will still favor GFS but other mdls similar for shrt
term.

Long term... inland high pres extends a wkng rdg acrs nrn nt2
wtrs Wed into Fri as wk low crossed srn wtrs. GFS and its
ensemble members are slower than other mdls. Plan to take blend
of 00z GFS/ECMWF while CMC global and UKMET are faster.
Preferred blend is similar to HPC Med rng guidance.

Seas...buoy 44024 came in with 31 ft at 06z after absence of 3
hr before which it rptd only 23 ft. This is much higher than
nearby rpts with mult grid ww3 giving Max 25 ft. Will raise
values mainly outer nt1 wtrs to mid 20s given mdl initialization
is in doubt in this area. Otrw 00z wavewatch iii mdl guidance
has initialized well versus buoy/ship obs across the cstl/ofshr
wtrs...and apprs reasonable thru the fcst prd so will stick with
its gdnce for seas excp for near term adj noted abv.

Extratropical storm surge guidance...00z etss guidance
initializes well against obsvd conds. For the fcst it generates
Max pos values 1.5-2 ft early Mon bos-Cape Cod Bay and then 2-3
ft l.I and NJ CST including l.I. Sound. This values appr
reasonable.

.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...Gale today into Tue...hi confdc.
.Georges Bank...Gale today into Tue...hi confdc.
.S of New England...Gale today into Tue...hi confdc.

.Nt2 mid Atlc waters
.Hudson to balt cnyn...Gale today into Tue...hi confdc.
.Balt cnyn to Hague line...Gale today thru Tue...MDT confdc.
.Balt cnyn to Hatteras cnyn...Gale today into Tue...MDT confdc.
.Hatteras cnyn to Cape Fear...Gale today into Tue...MDT confdc.
.Cape Fear to 31n...None.

.Forecaster Bancroft. Ocean forecast branch.

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