Marine Interpretation Message
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000
AGNT40 KWNM 231452
MIMATN

Marine Weather Discussion for N Atlantic Ocean
NWS Ocean Prediction Center Washington DC
1052 AM EDT Sat Sep 23 2017

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

In the near term slowly weakening remains of Jose will remain
nearly stationary in the NE NT2 waters in next 36 hours with
model consensus favoring the 06Z GFS, with models dissipating
Jose into a trough Sun night. Will be carrying maximum winds of
30 kt today lowering to 25 kt tonight and to less than 25 kt Sun.

The latest preliminary NHC advisory on Hurcn Maria continues to
nudge the track of Maria westward per the model consensus but not
as far west as the 00Z UKMET (which takes it close to Outer
Banks by Wed) nor as slow as 00Z ECMWF with CMC global a fast
outlier. For the morning update for background grids use the 06Z
GFS through 21Z Wed which is close to NHC track and beyond 21Z
Wed with the NHC track moving up to 12 hours ahead of the GFS, to
more closely match the NHC positions used the 06Z GFS but time
shifted 12 hours faster. For seas used a 80/20 blend of the 00Z
ECMWF WAM/00Z Wavewatch III, respectively, through 12Z Tue and a
20/80 blend of the two models (favoring the Wavewatch III)
through 21Z Tue. After that used the 06Z Wavewatch III except
time shifted 12 hours faster after 21Z Wed as was done for the
winds.

The KEY MESSAGES listed below still apply.

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PREVIOUS DISCUSSION...

Note: Warnings are preliminary, and will be modified based on
the next NHC advisory for Hurricane Maria.

KEY MESSAGES:

1. Swells from Maria are expected to increase along the coast of
the southeastern United States and will likely cause dangerous
surf and life-threatening rip currents for the next several
days.

2. Maria will move between the east coast of the United States
and Bermuda by the middle of next week, but it is too soon to
determine what, if any, direct impacts there might be in these
areas.

3. For more information on the flooding and rip current hazards
in the United States, please monitor information from your local
National Weather Service forecast office at www.weather.gov.

Over the short term, Post-Tropical Cyclone Jose is still
forecast to weaken over northern NT2 waters today through Sun,
and then likely dissipate by Mon. The preliminary 06Z OPC-NCEP
surface analysis indicated that Post-Tropical Cyclone Jose was
centered near 39N 69W with a central pressure of 1004 mb. It will
drift toward the east and southeast through tonight into Sun,
and then stall later Sun into early Mon over NE NT2 waters as it
dissipates. An evening ASCAT pass indicated a small area of gale
force winds just west of the center of Jose. The latest
observations indicate that the winds are continuing to diminish,
and will likely fall to below gale force by the time of the
forecast issuance around 0500 AM EDT. The 00Z models are in
pretty decent agreement regarding the future of Jose and the
surrounding weather features today into early Sun. We will
populate using the 00Z GFS 10 meter winds during this time frame,
with no major changes anticipated from the previous forecast for
the early morning package.

The main forecast challenge will continue to be the future track
and intensity of Hurricane Maria currently located to the east
of the Bahamas. Nearly all of the 00Z model guidance suggests
that Maria will trend further to the west. We expect tropical
storm to hurricane conditions to spread north with Maria, and
reach SE NT2 waters Sun afternoon, and then spread further north
into portions of the NT2 waters Sun night into Wed night. The
early morning package will be based on the latest NHC advisory
on Maria. Please closely monitor the latest NHC advisory, WFO
coastal forecast, and OPC forecast over the next few days.

As far as sea heights are concerned, the latest observations
indicate that the 00Z Wavewatch III is running around 2 feet too
high over most of the NT1 into the northern NT2 waters early
this morning, with the ECMWF WAM a little closer to these
observations. For the early morning package we will use a 80
percent WAM, and 20 percent Wavewatch blend for today into early
Sun. Additional adjustments will be made for Sun afternoon
through Wed night, based on the latest NHC advisory on Maria.

.Extratropical Storm Surge Guidance...The surge along the
western Long Island, New Jersey and Delmarva coasts appears to
be running about 1/2 ft higher than is forecast by the latest
ESTOFS or ETSS. As post-tropical cyclone Jose continues to
weaken over the next few hours, these values should diminish as
well. For surge information related to Maria please see the
latest information provided by NHC.

.WARNINGS...Preliminary.

.NT1 New England Waters...
     None.

.NT2 Mid-Atlantic Waters...
.ANZ828...Inner Waters from Cape Charles Light to Currituck Beach Light...
     Tropical Storm Possible Wednesday night.
.ANZ925...Outer Waters from Baltimore Canyon to Hatteras Canyon...
     Tropical Storm Possible Tuesday into Wednesday.
     Hurricane Possible Wednesday night.
.ANZ830...Inner Waters from Currituck Beach Light to Cape Hatteras...
     Tropical Storm Possible Tuesday into Wednesday night.
.ANZ833...Inner Waters from Cape Hatteras to Cape Fear...
     Tropical Storm Possible Monday night into Wednesday night.
.ANZ930...Outer Waters from Hatteras Canyon to Cape Fear...
     Tropical Storm Sunday night.
     Tropical Storm Possible Monday.
     Hurricane Possible Monday night into Wednesday night.
.ANZ835...Inner Waters from Cape Fear to 31N...
     Tropical Storm Possible Tuesday into Wednesday.
.ANZ935...Outer Waters from Cape Fear to 31N...
     Tropical Storm Sunday into Sunday night.
     Hurricane Possible Monday into Tuesday night.
     Tropical Storm Possible Wednesday into Wednesday night.

$$

.Forecaster Bancroft/Mills. Ocean Prediction Center.



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