marine weather discussion NWS ocean prediction center Washington DC 930 PM EDT sun 5 Jul 2009

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

In absence of evening Quikscat pass which has not yet arrived regular sfc obs show wnds to 20 kt srn nt1 areas ascd with departing mrtms low and S to SW to 20 kt ahd of inland low pres indc by cstl obs S of hat cnyn. Current fcst apprs on track. Near term prefer the 18z NAM sln bringing wnds up to gale balt to hat cnyns Mon mrng...while 18z GFS apprs to start gales nr CST S of hat in the late overnight prd and apprs to be having gridscale feedback problems. Otrw the GFS and NAM are in good agrmt and with the more consistent ECMWF soln. 18z GFS has slowed down its soln for the third low expected to cross srn wtrs late Tue and Wed to be more in ln with 12z ECMWF...but wnds in outer srn wtrs Wed appr overdone due to gridscale feedback. Hence will follow closely the 18z GFS for this fcst thru early Thu but will not extend gales farther S as indc by GFS for third low. Looking beyond...the GFS takes a fourth low acrs srn wtrs Thu into Fri alg more nrn track not sprtd by its ensemble members or 12z ec/UK/Gem global. Hence prefer 12z ECMWF for these later prds.

The 18z wave watch iii mdl solns cont to look consistent and will use for the fcst prd. The gridscale feedback problems noted abv Apr to be small enuf in duration and spatial extent and the lows ovr srn wtrs late in week weak enuf to not have big impact on wave mdl fcst.

Previous discussion... update: 12z GFS and ECMWF solns cont to look consistent with prev runs...and are still in vry gud agreemnt over the ofshr wtrs into Tue. Am not planning to make any signif changes to the current fcst trend.

Seas...12z wavewatch iii mdl soln looks vry consistent with the 06z run.

.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...none. .Georges Bank...None. .S of New England...None.

.Nt2 mid Atlc waters... .Hudson to balt cnyn...none. .Balt cnyn to Hague line...None. .Balt cnyn to Hatteras cnyn...Gale Mon...MDT confdc. .Hatteras cnyn to Cape Fear...None. .Cape Fear to 31n...None.

.Forecaster Bancroft/Scovil. Ocean forecast branch.

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