marine weather discussion for N Atlantic Ocean NWS ocean prediction center Washington DC 900 am EDT Wed 23 Apr 2014
.Forecast discussion: major features/winds/seas/significant .Weather for the North Atlantic ocean W of 50w from 30n to 50n.
NOAA buoy 44066 just increased to 23 g 27 kt last hr. This increasing trend will continue over coastal and offshore waters this afternoon into Thu. Have high level of confidence with previously forecast gales this afternoon thru Thu ngt. There is some potential for winds to briefly reach storm force Thu evening over nern nt2 zones specifically anz905 and anz910 where SSTs are in 23 to 26 c range. 00z hi res ECMWF indicates 50 to 60 kt 925mb winds which could mix given low lvl lapse rates -12 to -14 here. Will wait for 12z guidance before upgrading gales over these zone as not enough confidence at this time. In the Med range over the last few run the GFS has become more in line with the weaker ECMWF with cold front and dvlpg sfc low(s) along front Fri ngt thru Sat ngt. By sun GFS is less progressive and also further N with closed upper low and associcated strengthening sfc low near Nova Scotia. Past few gefs runs appear to better support ECMWF so will maintain continuity in this mornings updates which favored 00z ECMWF.
06z multigrid wavewatch iii is 1 to 2 ft too high with sig WV hgts just off mid Atlc coast this morning. As in previous forecast for later this afternoon into Fri the slightly hier 00z ECMWF wave mdl is favored with NW gales.
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A trof nr the mid Atlc coast wl cont to mov into the offshr early this mrng and wkn. Avlbl mdl guid movs low pres E ovr inland areas Maine early this mrng...then movg se into the glf of Maine this aftn. An assoc cd fnt movs E into the offshr wtrs tdy and passes E of the much of the offshr wtrs this aftn with the exception of the far srn areas of the mid Atlc offshr wtrs. Mdls are smlr with gales dvlpg by this aftn ovr the mid Atlc and into the New England wtrs tngt...then shifting E of the nrn mid Atlc and New England wtrs by Thu ngt as strengthening low pres passes E of the offshr areas. By Fri wk high pres movs E acrs the offshr wtrs. Mdls differ with low pres that movs ewd into the nrn offshr wtrs ovr the weekend. The GFS conts to Show Low pres movg ewd into the nrn New England wtrs Sat while the UKMET/Gem hav svrl lows movg into the offshr wtrs with the first low pres movg E acrs the far nrn mid Atlc wtrs Sat...and a second low movg E into the nrn New England wtrs sun. Attm prefer the Gem/UKMET which is smlr to the 12z ECMWF guid which showed a smlr scenario. Wl await 00z ECMWF before making final decision on how to handle this with grids.
.Seas...The multigrid wwiii look OK init...altho with gales that dvlp tdy thru Thu ngt blv the wwiii is on the low side. Wl likely blend the wwiii guid with the 00z ECMWF WV guid when it comes in.
.Extratropical storm surge guidance...GFS guid looks good overall with gales that dvlp tdy into Thu ngt. The estoffs rmns consistent in dvlpg a neg surge of 1 to 2 ft off the mid Atlc and srn New England coast Wed ngt thru Thu ...which dmnsh late Thu ngt into early Fri. The etss values rmn consistent and are less than 1 ft thru this time pd.
.Nt1 New England waters... .anz800...Gulf of Maine... gale Thu. .Anz805...Georges Bank east of 68w... gale tonight into Thu night. .Anz900...Georges Bank west of 68w... gale tonight into Thu night. .Anz810...South of New England... gale tonight into Thu. .Anz815...South of Long Island... gale tonight into Thu.
.Nt2 mid Atlc waters... .anz820...Hudson Canyon to Baltimore Canyon... gale tonight into Thu. .Anz915...Hudson Canyon to the great South Channel... gale tonight into Thu. .Anz920...Baltimore Canyon to the great South Channel... gale today into Thu. .Anz905...The great South Channel to the Hague line... gale tonight into Thu night. .Anz910...East of the great South Channel and south of 39n... gale tonight into Thu night. .Anz825...Inner waters from Baltimore Canyon to Cape Charles Light... gale tonight. .Anz925...Outer waters from Baltimore Canyon to Hatteras Canyon... gale today into Thu.
.Forecaster Clark/Rowland. Ocean prediction center.