.Marine weather discussion for N Atlantic Ocean .NWS ocean prediction center Washington DC 1000 am EDT Fri 22 Sep 2017
.Forecast discussion...Major features/winds/seas/significant .Weather for the North Atlantic ocean W of 50w from 30n to 50n.
Note: warnings are preliminary, and will be modified based on the next NHC advisories for Post-tropical cyclone Jose and Hurricane Maria.
This mornings satellite presentation of Post-tropical Jose is better than was the case for most of the day yesterday. NOAA buoy 44008, which is about 50 nm north of the center of Jose, has been reporting 998mb over the past few hours. The buoy's anemometer is malfunctioning as it reports an inaccurate wind direction. However, the wind speed reports still appear OK. The large vessel which reported 50 kt just east of Nantucket at 10z has an elevated anemometer, and has since reported 41 kt. Given it's satellite appearance, we cannot rule out that there are 50 kt sustained winds over the northwest semicircle of the system. With a lack of any steering flow, the latest models are consistent that Jose will move very little over the next couple days remaining across the northern nt2 zones, while gradually weakening. It is unlikely that the offshore warning headlines will change with the next nt1/nt2 issuances which will be based on the 15z NHC advisory on Jose. The 06z wavewatch iii and 00z ECMWF wam are reasonably well initialized with the offshore and coastal wave heights this morning. A notable exception is just north of Cape Cod Bay where NOAA buoy 44013 is reporting 15 ft. Based on the latest observations, including a 0930z altimeter pass across the Gulf of Maine/Georges Bank/northeastern nt2 zones, will be boosting the previous wave height grids by about 10 to 15 percent near Jose over the near term forecast.
A large area of winds at 35 kt or higher associated with Post- tropical cyclone Jose, extending outward from the center of this cyclone roughly within 190 nm N semicircle, and 130 nm se and 160 nm SW quadrants. This data confirms information from the National Hurricane Center issued at 11 PM last evening. For the early morning package, we will again remain close to the latest advisory from NHC regarding Jose into the weekend, with the 00z models remaining consistent, and showing Jose dissipating over the northern nt2 waters, or S of Georges Bank, by Mon, as it drifts and meanders over these waters during the next couple of days. Winds are expected to diminish over the next day or two as the low slowly weakens. Winds below 35 kt are expected over the waters by midday Sat or earlier. For the early morning package we will populate grids with 00z GFS for today into early Mon, with no major change expected from the past few opc forecasts. Confidence levels remain near to above average over the waters through the weekend.
As for the medium range, we will again follow the advisory from the National Hurricane Center for Hurricane Maria. Maria is still forecast to bring tropical storm conditions to se nt2 offshore waters by Sun night, spreading north over se and east- central portions of the nt2 waters Mon into Tue night. For now, the latest NHC forecast track keeps hurricane force winds E of the offshore waters early next week. Overall, the 00z models are in fair agreement regarding the track of Maria as it passes near or E of the nt2 offshore waters early next week. Timing differences are noted with the 00z guidance with the 00z GFS and UKMET a tad faster, the 00z ECMWF and navgem slower, and the 00z Canadian Gem a further west outlier. Confidence levels in the forecast from Mon night through the end of the period are near to below average.
As far as seas are concerned once again, the 00z wavewatch and ECMWF wam have both initialized fairly well, and are within a foot or two of the current observations. These two models remain in pretty good agreement with the sea heights associated with Post-tropical cyclone Jose. For today into Sun night we will use a 50/50 blend of the wavewatch and wam guidance for our wave height grids. For Mon through Tue night we will wait to see the latest NHC advisory for Hurricane Maria and then attempt to populate our grids with something representative of the 5 am EDT NHC advisory.
.Extratropical storm surge guidance...Please refer to the latest local NWS WFO guidance in reference to any potential tropical storm surge.
NHC key messages for Post-tropical cyclone jose:
1. Tropical-storm-force winds, especially in gusts, are occuring within the Tropical Storm Warning area. These conditions are expected to continue through at least early today.
2. Minor coastal flooding is possible along portions of the coast of southern New England during the next few days. Please see products issued by local National Weather Service forecast offices.
3. Swells generated by Jose are affecting Bermuda and much of the U.S. East Coast, and will likely cause dangerous surf and rip current conditions for the next couple of days in these areas.
.Nt1 New England waters... .nt1 New England waters... .Anz805...Georges Bank west of 68w... tropical storm today into tonight. .Anz900...Georges Bank east of 68w... tropical storm today. .Anz810...South of New England... tropical storm today into tonight. .Anz815...South of Long Island... tropical storm today into tonight.
.Nt2 mid-Atlantic waters... .anz915...Hudson Canyon to the great South Channel... tropical storm today into tonight. .Anz920...Baltimore Canyon to the great South Channel... tropical storm today. .Anz905...The great South Channel to the Hague line... tropical storm today into tonight. .Anz910...East of the great South Channel and south of 39n... tropical storm today into tonight. .Anz925...Outer waters from Baltimore Canyon to Hatteras Canyon... tropical storm possible Tuesday. Hurricane possible Tuesday night. .Anz930...Outer waters from Hatteras Canyon to Cape Fear... tropical storm possible Monday into Monday night. Hurricane possible Tuesday into Tuesday night. .Anz935...Outer waters from Cape Fear to 31n... tropical storm possible Sunday night into Tuesday night.
.Forecaster Clark/Mills. Ocean prediction center.