marine weather discussion for N Atlantic Ocean
NWS ocean prediction center Washington DC
840 am EST Thu Dec 12 2013
.Forecast discussion: major features/winds/seas/significant
.Weather for the North Atlantic ocean W of 50w from 30n to 50n.
The 06z GFS has trended toward the 00z mdl consensus and the 00z
ECMWF. Hopefully this trend will cont for the 12z and aftn fcst
cycles. Ovrall we will not be making sig changes to the prev fcst
for the am update.
Summary...a cold fnt will move se across the nt1 and NE nt2 wtrs
today. Rdg will bld into the nt2 wtrs later today and
tonite...then pass E across the nt2 area Fri and Sat. A trof
will pass rapidly E across the nt1 wtrs early Fri. Another cold
fnt will drop S over the nt1 wtrs later Fri...then stall across
the nrn nt2 wtrs Fri nite into Sat. A dvlpg low will move NE to
the mid Atlc CST late Sat...pass NE across the Georges Bank wtrs
sun aftn...then move off well to the NE later sun into Mon. The
low will pull the warm fnt NE over the nt1 area sun...and a cold
fnt E across the nt2 wtrs. Another rdg will bld ofshr Mon...and
expand over all of the ofshr areas.
Models...00z NAM and 00z Med rng mdls are in gud overall
agreemnt durg the fcst prd. Only diff noted among the mdls
across the cstl/ofshr wtrs is one of timing of the dvlpg low for
the Sat into Mon timeframe...with gefs mean/ECMWF/NOGAPS/UKMET
slower than the GFS...and only the Gem faster than the GFS.
Since the 00z GFS looks too fast for Sat into Mon...am going to
use the more representative 00z ECMWF for the entire fcst prd.
Seas...mww3 under initialized by 1 to 2 ft over the nt1 wtrs
versus the buoys. Given the stg and active wx pattern expctd for
the nxt five days...prefer the ECMWF wam over the more
conservative mww3 thru sun...then going with a blend of the
ECMWF wam/mww3 for Mon as the deep low moves off to the E and
away from the ofshr areas.
Extratropical storm surge guidance...differences of about 1.0 ft
with neg surge values Delaware Bay Thu...with estofs values to
2.0 ft...while the more conservative etss is near 1.0 ft. Etss
is just a bit higher than etss over Cape Cod Bay sun mrng.
.Warnings...Preliminary. Any changes will be
coordinated through AWIPS 12 planet chat or by telephone:
.Nt1 New England waters...
.Gulf of Maine...gale Friday...Saturday...and Monday.
.Georges Bank...Gale Friday...Saturday...and Monday.
.South of New England...Gale tonight...Saturday.
.Nt2 mid Atlc waters...
.Hudson Canyon to Baltimore Canyon...gale Saturday.
.Baltimore Canyon to Hague line...Gale tonight...Saturday into Mon.
.Baltimore Canyon to Hatteras Canyon...Gale Saturday.
.Hatteras Canyon to Cape Fear...Gale Saturday into Sunday.
.Cape Fear to 31n...Gale Sunday.