marine weather discussion for N Atlantic Ocean NWS ocean prediction center Washington DC 315 PM EDT Wed Jun 28 2017
.Forecast discussion...Major features/winds/seas/significant .Weather for the North Atlantic ocean W of 50w from 30n to 50n.
Summary...the 12z NCEP surface analysis shows a 1012 mb low centered about 300 nm E of the nt1 area, with an associated cold front extending se from the low and across the outer zones of the southern nt2 waters. The analysis also shows a high pressure ridge building se into the offshore waters N and W of the cold front. Latest available ascat hi-res and ascat passes from a few hours ago indicate 15 to 20 kt winds in NE flow over the southern nt2 waters, with 5 to 15 kt winds elsewhere in the offshore waters.
Models...the 12z medium range models are in good agreement across the offshore waters during the forecast period regarding the flow pattern and timing of the main weather features, but disagree concerning the strength of SW flow expected over the nt1 waters for the late Thu through Sat night timeframe. The 12z GFS 10m solution looks like the most representative model solution and will be used for the wind grids over the entire forecast period, except am going to cap its winds at 30 kt for Thu night in deference to the 12z ECMWF/UKMET models which are a notch lower with the winds.
Seas...the 12z wna wavewatch and 12z ECMWF wam both initialized well over the offshore waters. Only minor differences were noted between the models for tonight through Mon night, so a 50/50 blend of the 12z wna wavewatch/ECMWF wam will be used over the entire forecast period to smooth out the model differences.
.Extratropical storm surge guidance...N/A.
.Nt1 New England waters... None.
.Nt2 mid-Atlantic waters... None.
.Forecaster Scovil. Ocean prediction center.