marine weather discussion
NWS ocean prediction center Washington DC
130 PM EST Tue 18 Nov 2008

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

Winds continue to slowly increase off the mid Atlc coast...as
44014 now gusting over 30 kt and was up to 10 ft at 17z. Gales
likely already occurring balt to Hatteras cnyn over glf
stream... given winds at 44014 which is NW of glf stream at 15c.
Vis Sat imgry also indicating that sfc low dvlpg nr 38n72w is
getting better organized...along with increasing tstm activity
near center. Over the short term...given 12z guidance which is
quite consistent in moving cyclone over nrn periphery of glf
stream as base of mid/upper lvl trof support shifts offshr tngt.
With such favorable dynamics alng with likely the strongest caa
of season thus far...have fairly hi fcst confdc with storm
warnings over balt cnyn to Hague line and balt to Hatteras
cnyns...especially over glf stream. 12z NAM and namp diverge
from model consensus as cyclone consolidates and accelerates
twrd the glf of St Lawrence Wed ngt/Thu. The NAM/namp seem to
key on the more srn low which results in a slower timing. Am
favoring GFS solution which is offered much support from
ECMWF/UKMET/Canadian. Warnings over most zones shud expire
Wed...with the exception over the ern zones...Georges Bank and
balt cnyn to Hague line...where will carry marginal gales into
Wed ngt. This maintains continuity with prev offshore fcst...and
overall no sig changes are planned over shrt term.

Then winds shud remain MDT over most zones Thu into Sat...as
models in good agreement in bringing a couple of clipper type
systems thru new engl and offshore Thu and again Fri. Thu system
does not have much upper support and is weaker than Fri system.
12z GFS/UKMET and 00z ECMWF are in above avg agreement with
timing of fri's amplifying upper trof alng ern Seaboard...and
agree that gales in yet another fairly strong caa event are
likely over climo favored nrn cnyns. So will maintain fcst
continuity with prev marginal gales Fri into Sat balt to Hague
line and balt to Hatteras cnyns. Upper lvl flow over ern US/W
Atlc shud then flatten sun with hgts rising. And will continue
with the diminishing trend with winds/seas late Sat thru sun.

Had a 11 ft ship report at 18z nr N wall of glf stream se of
balt cnyn indicaing that 12z wavewatch iii is way underdone.
Will continue to make sig upward adjustments to seas over short
term espclly over glf stream and areas with storm force winds.
Otw... will follow guidance pretty closely thru remainder of
fcst period.

.Warnings/forecast confidence...Preliminary. Any changes will be
coordinated through AWIPS 12 planet chat or by telephone:

.Nt1 New England waters...
.Gulf of Maine...gale tngt into Wed...MDT to hi confdc.
.Georges Bank...Gale tngt into Wed ngt...hi confdc.
.S of New England...Gale tngt into Wed...MDT to hi confdc.

.Nt2 mid Atlc waters...
.Hudson to balt cnyn...storm tngt into Wed se prtn...MDT to hi
confdc. Otw...gale tngt into Wed ngt...hi confdc.
.Balt cnyn to Hague line...Gale tngt into Thu...except storm
invof the Gulf Stream and then E portion tngt into Wed...MDT to
hi confdc. Gale Fri into Sat...MDT confdc.
.Balt cnyn to Hatteras cnyn...Gale tngt into Wed...except storm
invof the Gulf Stream late Tue into Wed...MDT to hi confdc. Gale
Fri into Sat...MDT confdc.
.Hatteras cnyn to Cape Fear...Gale tngt into Wed...hi confdc.
.Cape Fear to 31n...Gale today and tngt...MDT confdc.

.Forecaster Clark. Ocean forecast branch.

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