HS 100

marine weather discussion NWS ocean prediction center Washington DC 702 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.

Note: after hurcn conference call with remnants of Ida approaching the SW nt2 waters plan to weaken low off the mid Atlc coast Wed and Thu. For this package will take down mention of storm for nt2 and keep gale force in N to NE flow.

The latest qscat pass showed SW winds 15 to 20 kt from the VA CAPES to Cape Cod and SW 20 to 30 kt over the Gulf of Maine. S of the VA CAPES to Cape Lookout winds were SW 10 to 15 kt and S of Cape Lookout variable 5 to 15 kt. Seas were 3 to 6 ft across the area with the exception of the NE Gulf of Maine where in the stronger SW flow seas had built to 6 to 9 ft. At 12z buoy 44027 near 44n 67w reported 9 ft.

High pres extends across the nt2 waters with a ridge extending NE just E of the nt1 area. A cold front will move through New York state and will move off the coast this morning passing se of nt1 by late afternoon. The weak front will stall over the central nt2 waters and either dissipate or move back N as a warm front Mon as a second high pres area move across nt1.

The model are in fair agreement into Tue then have problems with Wed and Thu. Have a low move off the Carolina coast Wed and deepening to a storm as it moves E across the area. The storm force winds will be N and W of the low over the nrn nt2 waters with gale force winds N to the Gulf of Maine and S to 31n. The last three runs of the GFS have been slower with the low now only abt 90 nm E of Cape Hatteras by Thu morning. From yesterday the GFS also had storm over New England S the track is shifting to the S. The last three runs have been more consistent with the track arnd 37n. This would put the strongest gradient over the N nt2 waters.

For the update will keep gale for nt1 without changes. If the low slows will have to keep gale up in Gulf of Maine into Thu but think the track will be far enough S to keep any mention of storm S of nt1. For nt2 will keep warnings in place.

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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 into Thu...low confdc. .Balt cnyn to Hague line...Gale Wed into Thu...low confdc. .Balt cnyn to Hatteras cnyn...Gale Wed into Thu...low confdc. .Hatteras cnyn to Cape Fear...Gale Wed into Thu...low confdc. .Cape Fear to 31n...Gale Wed into Thu...low confdc.

.Forecaster oszajca/vukits. Ocean forecast branch.