AGNT40 KWNM 290807 MIMATN Marine Weather Discussion for N Atlantic Ocean NWS Ocean Prediction Center Washington DC 407 AM EDT Thu Apr 29 2021 .FORECAST DISCUSSION...Major features/winds/seas/significant .weather for the North Atlantic Ocean W of 50W from 30N to 50N. The latest NCEP surface analysis shows a frontal boundary across the NT1 offshore waters this morning, and a high pressure ridge over the srn NT2 zones. In between the two features, the analysis shows a tightened pressure gradient across the nrn NT2 waters, indicating enhanced SW flow across the Gulf Stream. Ascat wind retrievals from 02Z late last night showed winds to 30 kt in the region ahead of the front with the highest conditions over the Gulf Stream. This matches up well with the previous wind grids, and the 00Z models agree on 30 kt max winds in this region for today as a frontal wave develops to the E of the region. The models do show higher winds just above the surface over the warmer SSTs, with GFS/ECMWF 925 mb winds indicating 40 kt over the Gulf Stream in nrn NT2. Although would not rule out an occasional gale force gust mixing to the surface, am not expected sustained gales for today with this wave as the models are not supporting that scenario. As such, am planning on keeping max winds at 30 kt for today. The 00Z models then show an active pattern continuing over the offshore waters through the remainder of the forecast period, with the guidance having a strong signal for the development of gale force conditions in the SW flow ahead of the next cold front tonight and Fri, and then in the cold air advection behind the front Fri night and Sat. The previous forecast had gale headlines up with this system consistent with the GFS winds, and confidence remains above average with them as a result of the strong consensus. As such, am planning on continuing with them in the next forecast package. Also, am planning on staying near the previous grids into Sat with only minor changes. The 00Z GFS then shows another strong cold front moving across the W Atlc Sun and Sun night, and again shows another round of gales developing ahead of it. However, the rest of the 00Z models are weaker with the winds than the GFS, which has also trended a little weaker from the 18Z run. As such, confidence is below average on the prospect of gales with this system. The previous forecast went up to 25 kt for Sun and Sun night, which seems reasonable considering the large spread in the models. As such, am planning on staying near this intensity for the next forecast package, and will be blending the 00Z GFS and ECMWF with the previous wind grids from Sat night through the rest of the forecast period as a compromise solution. .SEAS...In order to match up with the wind grids, am planning on staying near the previous wave height grids into Sat. Will then transition to a blend of the 00Z GFS Wave and ECMWF WAM models with the previous wave height grids through the rest of the forecast period. .EXTRATROPICAL STORM SURGE GUIDANCE...No significant positive surge events are expected during the next couple of days. Please monitor products from coastal National Weather Service offices for detailed water level information. .WARNINGS...Preliminary. .NT1 New England Waters... .ANZ805...Georges Bank west of 68W... Gale Friday night. Gale Possible Saturday. .ANZ810...South of New England... Gale Friday night. Gale Possible Saturday. .ANZ815...South of Long Island... Gale Friday night. Gale Possible Saturday. .NT2 Mid-Atlantic Waters... .ANZ820...Hudson Canyon to Baltimore Canyon... Gale tonight. Gale Friday night. Gale Possible Saturday. .ANZ915...Hudson Canyon to the Great South Channel... Gale tonight into Friday night. Gale Possible Saturday. .ANZ920...Baltimore Canyon to the Great South Channel... Gale tonight into Friday night. Gale Possible Saturday. .ANZ905...The Great South Channel to the Hague Line... Gale tonight into Friday night. Gale Possible Saturday. .ANZ910...East of the Great South Channel and south of 39N... Gale tonight into Friday night. Gale Possible Saturday. .ANZ825...Inner Waters from Baltimore Canyon to Cape Charles Light... Gale tonight. Gale Friday night. .ANZ828...Inner Waters from Cape Charles Light to Currituck Beach Light... Gale tonight into Friday night. .ANZ925...Outer Waters from Baltimore Canyon to Hatteras Canyon... Gale tonight into Friday night. Gale Possible Saturday. .ANZ830...Inner Waters from Currituck Beach Light to Cape Hatteras... Gale tonight into Friday. .ANZ833...Inner Waters from Cape Hatteras to Cape Fear... Gale tonight into Friday. .ANZ930...Outer Waters from Hatteras Canyon to Cape Fear... Gale tonight into Friday. $$ .Forecaster Kells. Ocean Prediction Center.