marine weather discussion for N Atlantic Ocean NWS ocean prediction center Washington DC 719 am EDT Tue Mar 28 2017
.Forecast discussion...Major features/winds/seas/significant .Weather for the North Atlantic ocean W of 50w from 30n to 50n.
Due to a system upgrade, the next offshore and high seas text forecasts will be issued by the Tropical Analysis and Forecast Branch at the National Hurricane Center.
----------------------------------------------------------------- Previous discussion...
The 00z surface analysis indicated low pressure over the northern Gulf of Maine waters, with warm front extending southeast and stationary front west. Several ascat passes from late Monday evening with decent coverage over nt2 waters but few returns over nt1 waters indicated winds less than 20 kt. There was a small area of gales noted just east of the Gulf of Maine.
The 00z models continue to be in very good agreement through most of the forecast period. There continue to be some differences with the strong low forecast to move off the mid Atlantic coast later Friday night into Saturday, although the models are in better agreement than yesterday morning. For the period from today through Thursday, the models all continue to be in decent agreement on the low forecast to move off the mid Atlantic coast this evening, then track east across the far northern nt2 waters and southern nt1 waters tonight, then moving east of the offshore waters Wednesday and intensifying. Will continue to use the first sigma level tool to enhance the stronger winds over the more unstable areas which will maintain gales over the northeast nt2 waters Thursday. High pressure ridge will then build offshore Thursday night through Friday. The next low will then move offshore later Friday night. The 00z GFS is similar to the 12 and 18z runs with the track, although it is slightly weaker compared to especially the 12z run from yesterday. The UKMET continues to be further north with the track and also deeper, while the ECMWF and CMC are closer to the GFS track albeit slightly north of the GFS. At the present time considering the GFS has had fewer changes from run to run, feel the best course is to use official grids during this period to maintain continuity as much as possible and will keep same warning headlines. Then will use the 00z GFS winds for remainder.
.Seas...The 06z sea state analysis indicated that the mww3 and ECMWF wam both matched up well with the observed seas. Plan on using the mww3 through the period except during the late Friday through Saturday night period will use official grids similar to winds which are based on 50/50 blend of mww3 and ECMWF wam from 12z.
.Extratropical storm surge guidance...N/A.
.Nt1 New England waters... .anz810...south of New England... gale possible Saturday night.
.Nt2 mid-Atlantic waters... .anz915...Hudson Canyon to the great South Channel... gale possible Saturday night. .Anz920...Baltimore Canyon to the great South Channel... gale possible Saturday. .Anz905...The great South Channel to the Hague line... gale Wednesday night. Gale possible Thursday. Gale possible Saturday night. .Anz910...East of the great South Channel and south of 39n... gale Wednesday night. Gale possible Saturday into Saturday night. .Anz828...Inner waters from Cape Charles Light to Currituck Beach Light... gale possible Friday night. .Anz925...Outer waters from Baltimore Canyon to Hatteras Canyon... gale possible Friday night into Saturday. .Anz830...Inner waters from Currituck Beach Light to Cape Hatteras... gale possible Friday night. .Anz833...Inner waters from Cape Hatteras to Cape Fear... gale possible Friday night. .Anz930...Outer waters from Hatteras Canyon to Cape Fear... gale possible Friday night into Saturday.
.Forecaster Kells/kosier. Ocean prediction center.