Marine Interpretation Message
Issued by NWS

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AGNT40 KWNM 290223
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
923 PM EST FRI NOV 28 2014

.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT
.WEATHER FOR THE NORTH ATLANTIC OCEAN W OF 50W FROM 30N TO 50N.

HGH CLDS OVR THE REGION WITH NO LITGNG ATTM. THE RADAR DOES NOT
SHO ANY TSTMS CELLS OVR THE REGION. AT 00Z LOE PRES 996 MB APPROX
540 NM NE OF THE BALT CNYN WTRS. INLAND HGH PRES 1028 MB OVR NC/SC
HAS ARIDGE ACRS THE MID ATLC STATES AND THE SE STATES. THE PRES
GRDNT BTWN THE TWO SYNOP SYSM OVR THE NRN AND CNTRL WTRS IS JUST
TIGHT. THE MAX WINDS ARE 20 KT AND THE LAST ASCAT PASS AT 1535Z
MISSED MOST OF THE CNTRL REGION WHERE WINDS WERE STRNGR.THE SEAS
ARE EQUALLY MEDIOCORE WITH ONLY 11 FT PEAKS OVR THE ERN PARTS. THE
GLBL MDLS ARE IN DECENT AGRMNT OVR THE SHORT. HGH PRES WILL MOVE E
INTO THE CNTRL REGION AND KEEP A SLCK PRES GRDNT. WILL CONTNE WITH
NO WRNGS IN THE FCST AND WILL STAY WITH GFS FOR THIS UPDATE.


-----------------------------------------------------------------
PREVIOUS DISCUSSION...

OF IMMED CONCERN FOR THIS FCST IS STATUS OF NW GALES OVER OUTER OFFSHORE
WATERS...E OF 70W AND S OF GEORGES BANK. A 1000 MB SFC LOW WAS
LOCATED NR 39N63W AT 12Z AND IS MOVING NE AT 35 KT. THIS LOW IS
ABOUT 4 MB DEEPER THAN ALL THE 00Z GLOBAL MODEL SHORT RANGE FCST.
AND...NONE OF THE 12Z MODELS INITLD DEEP ENOUGH WITH THIS LOW.
THUS...EXPECT WINDS TO BE STRONGER AROUND THIS LOW THAN MODELS
GUESS...WHICH AS MEASURED BY THE 14Z ASCAT PASS...WINDS WERE GALE
FRC OVR ERN BALT CANYON...A FEW KTS HIGHER THEN THE GFS 30M WINDS.
FOR TNGT...WL BEGIN WITH NW GALES OVR ZONES ANZ905 AND ANZ910...AND
N TO NW 20 TO 30 KT ELSEWHERE E OF 70W. OTW...WINDS DMNSHNG TO
LGT AS LRG HGH PRES BUILDS E OVR THE W ATLC.

WINDS WILL BCMS SW BY LATE SAT AS THE CENTER OF THE HIGH MVS E OF
THE REGION. SW WINDS WILL INCRS AS NEXT COLD FRONT APPCHS. MODELS
AGREE ON WINDS INCRSNG TO 20 TO 30 KT N OF BALT CNYN BY LATE
SUN...AND SUSTAINING INTO MON. AFT 00Z MON...THE GFS SURGES AHEAD
WITH THE COLD FRONT...PUSHING IT SE ABOUT 6 TO 9 HOURS FASTER THAN
THE ECMWF/UKMET...UNTIL ABOUT 12Z TUE WHEN THE THREE MODELS ARE IN
BTTR AGREEMENT. THE GEM IS A SLOWER OUTLIER AND THE PARALLEL GFS
LKS LIKE TH OPRTNL RUN. ALOFT...THE GFS BCMS A GLOBAL OUTLIER IN
THE HANDELING OF THE UPR LOW NR 140W AND BCMS MORE UNHARMONIOUS
WITH GLOBAL CONSENSUS. THUS...WILL USE THE UKMET FROM 00Z MON
ON...FOR THE REST OF THE FCST. THE UKMET IS VRY SMLR TO THE 00Z
ECMWF. WL INCRS THE N TO NW WINDS SLGTLY MON INTO TUE BEHIND THE
COLD FRONT...WITH WINDS TO 30 KT. THE UKMET CAN UNDERPLAY
THESE...AND ALSO LOWER WINDS IN THE SRLY FLOW OVR THE NTHRN WATERS
WED AHD OF THE NEXT COLD FRONT. LATE WED AND WED NIGHT...THE
UKMET/ECMWF BRINGS NEXT COLD FRONT SWEEPING SE ACROSS THE OFFSHORE
WATERS. THE GFS THROWS A RDG WWRD INTO THE MID ATLC RGN AND HOLDS
THE NEXT FRONT INLAND THRU 12Z THU AND WL NOT BE USED. WL FCST NW
WINDS INCRSNG TO 25 BEHIND THIS SECOND COLD FRONT.


.SEAS...THE MULTIGRID WAVEWATCH III INITLD WELL. AT 18Z...SEAS ARE
WITHIN A FT OF THE MODEL FCST. FCST GDNC LOOKS GOOD...EXCEPT WILL
TRANSISITON OVR TO THE ECMWF WAM AFT 12Z MON AS THE ECMWF WINDS
MORE ACCURATELY REFLECT THE FCST.


.EXTRATROPICAL STORM SURGE GUIDANCE...BY LATE TUE...THE ESTOFS
DVLPS A SURGE OF 1 TO 2 FT IN THE NE FLOW...AND SPREADS THE SURGE
N THRU THE MID ATLC COAST TUE NGT. CONSIDERING THE GFS IS TOO FAST
WITH THE FRONT...THE TIMING OF THE SURGE IS LIKELY TOO SOON.



.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
     NONE.

.NT2 MID ATLC WATERS...
     NONE.

$$

.FORECASTER MUSONDA/PROSISE. OCEAN PREDICTION CENTER.



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