Marine Interpretation Message
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AGNT40 KWNM 231859
MIMATN

Marine Weather Discussion for N Atlantic Ocean
NWS Ocean Prediction Center Washington DC
159 PM EST MON JAN 23 2017

.FORECAST DISCUSSION...Major features/winds/seas/significant
.weather for the North Atlantic Ocean W of 50W from 30N to 50N.

Over the short term, the 12Z models remain in very good agreement
that the developing triple point surface low now moving NE off
the N Carolina coast will track NNE up the mid Atlantic coast
tonight into early Tue while intensifying into a nor`easter...
continue slowly NE across the NT2 waters later Tue/Tue
night...then move off the NE Wed. In regards to the forecast track
of this low, the 12Z GFS solution looks representative since its
supported best by the 12Z GEFS Mean and 12Z UKMET/ECMWF. In
regards to the associated forecast gradients, would prefer the
slightly stronger 12Z NAM/GFS/GEM solutions. Therefore plan on
populating our forecast wind grids for tonight through Wed night
with our smart tool that will place stronger 12Z GFS first sigma
level winds in unstable and weaker 12Z GFS 10m winds in stable
areas. So since these 12Z GFS winds are very consistent do not
plan on any significant short term timing and/or areal coverage
changes to the previously forecasted gale/storm warnings with this
system.

In the long range, versus its previous respective runs, the 12Z
GFS remains consistent in forecasting a cold front to push SE
across the waters Thu/Thu night, which overall is supported by the
other 12Z global models, with gale force associated winds mainly
near the gulf stream across the NT2 waters. So as a compromise,
would favor a blended 12Z GFS/ECMWF solution for this fropa and
with this in mind will populate our wind grids with a 50/50 blend
of the 12Z GFS 10m/first sigma level winds and 12Z ECMWF boundary
layer (BL) winds on Thu into Fri.

Then by late Fri through Sat night to varying degrees the 12Z
models all forecast a broad upper trough to persist near the E
coast while several embedded short wave troughs rotate through its
base. At the surface, this upper level pattern will play out with
a series of surface troughs passing SE across the waters which
will in turn maintain a moderate strong (generally up to 25-30 kt)
WNW gradient throughout much of the waters. So in an attempt to
smooth out their differences and to develop a compromise, plan on
populating with a 33/33/33 blend of the 12Z GFS first sigma winds
and 12Z UKMET/ECMWF BL winds for late Fri through Sat night.

.Seas...The higher 12Z ECMWF WAM has initialized the current seas
better than the 12Z Wavewatch III and as a result will populate
our forecast wave grids with the 12Z ECMWF WAM for tonight. Then
for a compromise and since a blended 12Z GFS/ECMWF solution will
often be used, will transition to populating with a 50/50 blend of
the 12Z Wavewatch III and 12Z ECMWF for Tue through Sat night.

.Extratropical Storm Surge Guidance...In the strong Ely gradient
forecast to shift Nwd across the Nrn waters tonight Tue, the 12Z
ESTOFS remains consistent in forecasting a slightly more
significant surge (up to 3-4 FT,which at times may be too low) to
spread N up the coast from Delaware to SW New England than
forecast by the 12Z ETSS. Would recommend continuing to favor the
higher 12Z ESTOFS solution.

.WARNINGS...Preliminary.

.NT1 New England Waters...
.ANZ800...Gulf of Maine...
     Gale tonight.
     Storm Tuesday.
     Gale Tuesday night.
.ANZ805...Georges Bank west of 68W...
 Storm tonight. Gale Tuesday. Gale Possible Thursday night.
.ANZ900...Georges Bank east of 68W...
     Gale today into Tuesday.
     Gale Possible Thursday night.
.ANZ810...South of New England...
 Storm tonight. Gale Possible Thursday night.
.ANZ815...South of Long Island...
 Storm tonight. Gale Tuesday night. Gale Possible Thursday
night.

.NT2 Mid-Atlantic Waters...
.ANZ820...Hudson Canyon to Baltimore Canyon...
 Storm tonight. Gale Tuesday into Tuesday night. Gale Possible
Thursday night.
.ANZ915...Hudson Canyon to the Great South Channel...
 Storm tonight. Gale Tuesday into Tuesday night. Gale Possible
Thursday night.
.ANZ920...Baltimore Canyon to the Great South Channel...
 Gale tonight into Wednesday. Gale Possible Thursday into
Thursday night.
.ANZ905...The Great South Channel to the Hague Line...
 Gale tonight into Tuesday. Gale Possible Thursday night.
.ANZ910...East of the Great South Channel and south of 39N...
 Gale tonight into Wednesday. Gale Possible Thursday into
Thursday night.
.ANZ825...Inner Waters from Baltimore Canyon to Cape Charles Light...
     Gale today.
     Gale Tuesday into Tuesday night.
.ANZ828...Inner Waters from Cape Charles Light to Currituck Beach Light...
     Gale Tuesday into Tuesday night.
     Gale Possible Thursday.
.ANZ925...Outer Waters from Baltimore Canyon to Hatteras Canyon...
     Gale today into Wednesday.
     Gale Possible Thursday into Thursday night.
.ANZ830...Inner Waters from Currituck Beach Light to Cape Hatteras...
     Gale Tuesday into Tuesday night.
     Gale Possible Thursday.
.ANZ833...Inner Waters from Cape Hatteras to Cape Fear...
     Gale Possible Thursday.
.ANZ930...Outer Waters from Hatteras Canyon to Cape Fear...
     Gale today into Tuesday night.
     Gale Possible Thursday into Thursday night.
.ANZ835...Inner Waters from Cape Fear to 31N...
     Gale today into Tuesday.
     Gale Possible Wednesday night into Thursday.
.ANZ935...Outer Waters from Cape Fear to 31N...
     Gale today into Tuesday.
     Gale Possible Thursday.

$$

.Forecaster Vukits. Ocean Prediction Center.



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