HS 100

marine weather discussion for N Atlantic Ocean NWS ocean prediction center Washington DC 312 PM EDT Fri 24 may 2013

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

Summary...a cold fnt will pass E across the ofshr wtrs this aftn thru Sat. Low pres will move NE over the srn nt1 wtrs this aftn into tonite...then turn N and pass across the nrn nt1 wtrs Sat into sun. The low will move off to the NE late sun and Mon. Rdg will bld se into the srn nt2 wtrs sun...expand over the nrn nt2 wtrs Mon...then bld across the nt1 area Tue. The rdg will shift E of the nt1 area Wed...as a warm fnt lifts NE over the nrn nt2 and srn nt1 wtrs.

Models...the 12z NAM and 12z Med rng mdls are in gud overall agreemnt thru the fcst prd...with ECMWF and GFS in closest agreemnt across the cstl/ofshr wtrs. 12z ECMWF/UKMET look a bit wkr with the S to SW flow ahd of the cold fnt into Sat...while the 12z NAM/Gem are stgr...and 12z GFS/NOGAPS are median solns wrt strength of the S to SW flow. Since the GFS has stg support from the ECMWF...and because the GFS looks like a gud median soln...will be favoring the 12z GFS for the upcoming ofshr wtrs fcst package. Am not planning to make any signif changes to the current fcst trend.

Seas...the 12z multigrid ww3 and 12z ECMWF wam both initialized well over the cstl/ofshr wtrs. These mdls are in gud overall agreemnt during the fcst prd...with only some minor diffs noted on Sat and sun. Will use the multigrid ww3...except may go with a blend of the multigrid ww3 and ECMWF wam on Sat and sun to smooth some of the diffs.

Extratropical storm surge guidance...N/A.

.Warnings/forecast confidence...Preliminary. Any changes will be coordinated through AWIPS 12 planet chat or by telephone:

.Nt1 New England waters... .Gulf of Maine...none. .Georges Bank...None. .South of New England...None.

.Nt2 mid Atlc waters... .Hudson Canyon to Baltimore Canyon...gale Sat into early sun...low confdc. .Baltimore Canyon to Hague line...Gale this aftn into sun...mod to high confdc. .Baltimore Canyon to Hatteras Canyon...Gale this aftn...high confdc. Gale Sat into sun...mod confdc. .Hatteras Canyon to Cape Fear...None. .Cape Fear to 31n...None. $$

.Forecaster Scovil. Ocean prediction center.