marine weather discussion for N Atlantic Ocean NWS ocean prediction center Washington DC 900 am EST Mon 8 Feb 2016
.Forecast discussion: major features/winds/seas/significant .Weather for the North Atlantic ocean W of 50w from 30n to 50n.
Hurricane force low near 36.3n67.5w at 13z is moving NE at about 35 kt. Strongest winds have shifted E of offshore waters and will be downgrading offshore hurricane force wind warnings to storm warnings with this mornings nt2 update. Previous wind grids look reasonable this morning and will not be making any significant adjustments. Buoy observations over past few hours indicating that both 06z wavewatch iii and 00z ECMWF wam are about 20 to 30 percent underdone over W Atlc this morning. The 00z ECMWF wam has a slightly better handle than 00z/06z wavewatch iii over New England and northern mid Atlc offshore waters in strong NE winds. The higher estofs appears to initially have a better handle than the etss with storm surge affecting New England coast and mid Atlc coast N of Cape Hatteras. These models are in agreement that surge should subside today and tonight as hurricane force low accelerates NE away from offshore waters.
--------------------------------------------------------------- ...Previous discussion...
Over the short term...earlier 0145z and 0232z high resolution ascat-b and ascat-a scatterometer passes confirmed that the strong sfc low nr 33n73w had hurricane force ascd winds. The new 00z mdls remain in excellent agrmt in rgrds to the fcst track of this low with it passing just se of Georges Bank this afternoon...then movg off to the NE tonite. In rgrds to the fcst strength of this system...based on its current impressive satellite signature suspect that its now bottoming out central pressure-wise. Therefore with the mdls also fcstg smlr ascd fcst gradients...plan on populating our fcst wind grids today with the 00z GFS 30m bl winds with just sm minor additional edits per the 00z UKMET/ECMWF. So since the GFS 30m bl winds were prevly used...anticipate making only minimal chngs to the prevly ascd wrngs for this system.
Then in response to a series of upr S/W trofs rotating thru the base of an upr l/W trof movg in the ern conus...by late tonite the 00z mdls are in rsnbl agrmt that another dvlpg sfc low and strong cold front wl mov ofshr into the nt2 wtrs...pass se of Georges Bank Tue...then mov off to the NE Tue nite whl yet another sfc low moves E off the nrn mid Atlc coast. The end result wl be a mod to strong wly gradient dvlpg thrut the nt2 wtrs. Vs its prev respective runs...the 00z GFS fcsts this low to intensify mr rapidly with sm hurcn force 30m bl winds dvlpg nr its center Tue afternoon acrs the outermost nt2 wtrs. For now with the other 00z mdls fcstg weaker solutions...wl cap the winds ascd with this low in the storm force range...highest acrs the outermost nt2 wtrs. Therefore as a compromise plan on populating with a 50/50 blend of the 00z GFS 30m and 10m bl winds for tonite thru Tue nite
In the long range...the 00z GFS/ECMWF...and to a slightly lesser degree the 00z UKMET...are in rsnbly good agrmt that the sfc low wl mov off to the NE Wed...flwd closely by another sfc low and cold front passing acrs the wtrs Wed nite...then intensify E of the area Thu/Thu nite maintaining a mod/strong wnwly gradient thrut much of the wtrs. For this gradient plan on contg to populate with a 50/50 blend of the 00z GFS 30m and 10m bl winds Wed thru Thu.
Then Fri/Fri nite...the disparity btwn the 00z global mdls increases sigly. Smlr to its prev 18z run...the 00z GFS fcsts a rel weak dvlpg sfc low to race NE acrs the nt2 wtrs Fri into Fri nite which is sprtd by its ascd 00z gefs mean and the 00z Gem. The 00z UKMET does not hv this feature at all and instead fcsts a weaker sfc low passing ofshr further N. The new 00z ECMWF has now come in much mr amplified and fcsts a rapidly intensfying sfc low to mov ofshr acrs the NW nt2 wtrs Fri nite (by 13/12z a 985 mb low S of cp cod vs its prev 12z run of a 1007 mb low in the Gulf of maine) with wdsprd gales and sm storm force ascd bl winds dvlpg. For now am not going to jump on this 00z ECMWF solution. Therefore to be mr in line with the latest wpc medium range guidance...with gnrly low fcst confidence wuld favor a solution closer to the 12z GFS/gefs/Gem. So wl cont with a 50/50 blend of the blend of the 00z GFS 30m and 10m bl winds thru Fri nite.
Seas...as a compromise...wl populate our fcst wave grids with a 50/50 blend of the 00z wavewatch iii and 00z ECMWF wam for today thru Wed nite. Then since the 00z GFS wl bcm favored...wl go with all 00z wavewatch iii Thu thru Fri nite.
.Extratropical storm surge guidance...N/A.
.Nt1 New England waters... .anz800...Gulf of Maine... storm today. Gale tonight. .Anz805...Georges Bank west of 68w... storm today. Gale tonight. Gale possible Thu night. .Anz900...Georges Bank east of 68w... storm today into tonight. Gale Tue. Gale possible Thu night. .Anz810...South of New England... storm today. Gale possible Thu night. .Anz815...South of Long Island... storm today. Gale possible Thu into Thu night.
.Nt2 mid Atlc waters... .anz820...Hudson Canyon to Baltimore Canyon... gale today. Gale possible Thu. .Anz915...Hudson Canyon to the great South Channel... storm today. Gale Tue night. Gale possible Wed. Gale possible Thu into Thu night. .Anz920...Baltimore Canyon to the great South Channel... storm today. Storm Tue. Gale Tue night. Gale possible Wed. Gale possible Thu into Thu night. .Anz905...The great South Channel to the Hague line... storm today into Tue. Gale Tue night. Gale possible Wed. Gale possible Thu into Thu night. .Anz910...East of the great South Channel and south of 39n... storm today. Gale tonight. Storm Tue. Gale Tue night. Gale possible Wed. Gale possible Thu into Thu night. .Anz825...Inner waters from Baltimore Canyon to Cape Charles Light... gale possible Thu. .Anz925...Outer waters from Baltimore Canyon to Hatteras Canyon... storm today. Storm Tue. Gale Tue night. Gale possible Wed into Fri night. .Anz830...Inner waters from Currituck Beach Light to Cape Hatteras... gale Tue. .Anz833...Inner waters from Cape Hatteras to Cape Fear... gale tonight into Tue. .Anz930...Outer waters from Hatteras Canyon to Cape Fear... gale today into tonight. Storm Tue. Gale Tue night. Gale possible Wed into Thu. Gale possible Fri into Fri night. .Anz835...Inner waters from Cape Fear to 31n... gale tonight into Tue night. Gale possible Wed into Wed night. Gale possible Fri into Fri night. .Anz935...Outer waters from Cape Fear to 31n... gale tonight into Tue night. Gale possible Wed into Wed night. Gale possible Fri night.
.Forecaster Clark/vukits. Ocean prediction center.