HS 100

marine weather discussion...updated NWS ocean prediction center Washington DC 205 am EST sun 8 Nov 2009

.Forecast discussion: major features/winds/seas/significant .Weather for North Atlantic ocean W of 50w from 30n to 50n.

The new 00z ECMWF has come in and thru the short term presents no sig fcst problems. But in the long range the 00z ECMWF has changed drastically vs its prev 12z run. The 00z ECMWF now joins the 00z GFS/Gem Camp of alwg the upr lvl energy FM Ida to either sprt its remnant sfc low (gem/ecwmf) and/or spawns a new frontal wave on the cold front off the se coast (gfs) and then tracks the deepening low NE acrs the srn/cntrl nt2 wtrs Wed into Thu. The 00z ECMWF by Thu bcms disturbing close to the 00z GFS and it now also fcsts solid storm force ascd bl winds to dvlp mainly acrs the outer nt2 wtrs. For now with stil a very low level of confidence plan on using a blended 00z GFS/Gem/ECMWF fcst track for low pres passing NE acrs the srn/cntrl nt2 wtrs Wed into Thu and wl go ahead and fcst psbl marginal storm wrngs for primarily the outer nt2 wtrs.

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Over the short term...the 00z mdls present no major problems. Per the 18z NAM/GFS...inadvof weakening cold fropa late early today wl cont to fcst Max SW winds up to 25 or 30 kt acrs the nt1 wtrs. Otherwise no sig short term chngs are planned to the prev ofshr fcsts.

In the long range...by Tue nite into Thu the latest mdls cont to offer sigly different solutions for the future path of T.S. Ida or its remnants as it is expected to interact with a strong cold front movg ofshr. Smlr to its prev 18z run...the 00z GFS conts to phase the srn and nrn upr streams with an ascd frontal low invof cp Hatteras Tue morning drifting slowly NE into early Thu whl deepening with ascd storm and hurcn force bl winds fcst to dvlp Wed into Thu acrs the cntrl/nrn nt2 and srn most nt1 wtrs. The 00z gefs has only a single ensemble member invof the 00z GFS low whicn lkly indicates that the GFS solution is overdone. The 00z global Canadian Gem vaguely sprts the GFS solution but is considerably slower and weaker than the GFS with its sfc low. The 00z UKMET/NOGAPS either keep what is left of Ida in the Gulf of Mexico (nogaps) and/or drift it E acrs Florida late (ukmet)...whl for the ofshr wtrs they focus on a strong cold fropa Tue nite/Wed flwd by strong high pres bldg ofshr Thu. For now with such large disparity btwn the mdls and per coord with HPC...with a very low level of confidence plan on favoring a blended 12z ECMWF and 00z gefs mean fcst solution which wl just focus on a strong cold fropa Tue nite/Wed which wl be in line with the latest HPC medium range guidance and require making only minimal long range chngs to the prev ofshr fcst package.

Overall the 00z wna wavewatch iii fcst seas look representative over the short term and wl not be deviated FM sigly. But in the long range since the 00z GFS solution wl not be favored...wl cont with fcst seas sigly lower than fcst by the mdl...smlr to the prev fcst package.

.Warnings/forecast confidence...Warnings are preliminary and are subject to change. Any changes will be coordinated through AWIPS 12 planet chat or by telephone.

.Nt1 New England waters... .Gulf of Maine...gale Wed...low confdc. .Georges Bank...Gale Wed...low confdc. .S of New England...Gale Wed...low confdc.

.Nt2 mid Atlc waters... .Hudson to balt cnyn...gale Wed...low confdc. .Balt cnyn to Hague line...Gale Wed bcmg storm Thu...low confdc. .Balt cnyn to Hatteras cnyn...Gale Wed bcmg storm Thu...low confdc. .Hatteras cnyn to Cape Fear...Gale Wed bcmg storm Thu...low confdc. .Cape Fear to 31n...Gale Wed into Thu...low confdc.

.Forecaster vukits. Ocean forecast branch.