marine weather discussion for N Atlantic Ocean NWS ocean prediction center Washington DC 853 am EST Fri Mar 6 2015
.Forecast discussion: major features/winds/seas/significant .Weather for the North Atlantic ocean W of 50w from 30n to 50n.
For the update...cold front extends FM 40n54w SW thru 35n65w... or 200 nm N of Bermuda to 31n75w. Main concern this mrng is status of gales off the se coast. Winds at the buoys just off the coast...Frying Pan Shoals...edisto as well as coastal obs show winds hv begun to dmnsh slightly ovr the past few hours. However...with winds directly opposed to the Gulf Stream...areas of gale force winds are still occuring over the Gulf Stream attm. Warnings expire at 15z and will let them run until then. Expect winds to cont to slowly dmnsh today as the large area of high pres builds E over the wrn Atlc. Seas are running close to gdnc...except off the se coast in the NE flow where seas are 1 to 3 ft abv model gdnc. Will adjst the fcst for current conds for the fcst update...otw little chng.
----------------------------------------------------------------- Previous discussion...
Summary...a stg cold fnt extending NE to SW over the cntrl and srn nt2 wtrs will pass se of the nt2 area today. A stg hi pres ridge will build ofshr into the wtrs behind the cold fnt today...then move E of the ofshr area tonite. Another cold fnt will aprch the new eng and mid Atlc coasts from the NW Sat...then pass se across the ofshr wtrs Sat nite into sun. Another ridge will move E across the ofshr wtrs late sun into early Mon. A third cold front will move E across the waters Mon. A Third Ridge will build in from the W Mon nite...then move E across the nt1 and nrn nt2 wtrs Tue and Tue nite.
Models...the 00z Med rng mdls are in gud agreemnt thru sun nite...so the representative 00z GFS 30m soln will be used to populate the wind grids for this prd. The 00z Med rng mdls are contg to show fairly signif diffs in timing and strength of the main wx ftrs over the Mon thru Tue nite timeframe...altho the 00z ECMWF/GFS appr to be in better agreemnt than the other mdls. Will use a 50/50 blend of the 00z ECMWF/GFS for Mon thru Tue nite as a comprimise soln to resolve the Med rng mdl diffs...since it has decent support from the latest wpc Med rng fcstr guidance.
.Seas...The 00z multigrid ww3 mdl initialized well over the ofshr wtrs...except for the Gulf of Maine where its sea hts are about 2 ft underdone...so the 00z mww3 sea hts will be adjusted upwards for today to account for this. The 00z ECMWF wam and 00z mww3 mdl guidance are in gud agreemnt for today thru sun nite...and will use the 00z mww3 mdl for the wave ht grids for this prd. Then will use a 50/50 blend of the 00z ECMWF wam/mww3 for Mon thru Tue nite to reflect the model preferences for that timeframe.
.Extratropical storm surge guidance...Estofs is fcstg a neg surge in the 1.0 to 1.5 ft range along the Georgia/South Carolina coast tonite.
.Nt1 New England waters... None.
.Nt2 mid Atlc waters... .anz905...the great South Channel to the Hague line... gale Sat night into sun. Gale possible sun into Sun night.
.Forecaster prosise/Scovil. Ocean prediction center.