Marine Interpretation Message
Issued by NWS

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AGNT40 KWNM 171932
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
232 PM EST WED 17 DEC 2014

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

14 UTC AND 15 UTC HIGH RESOLUTION ASCAT-A AND -B RETURNED GALES
E OF MID ATLC OFFSHORE WATERS E OF COLD FRONT...AND 20 TO 30 KT
BEHIND COLD FRONT OVER OUTER NT2 ZONES N OF HATTERAS CNYN. SFC
WINDS CLOSE TO GALE N OF OCCLUDED FRONT OVER GULF OF MAINE WHERE
ELEVATED MISM1 GUSTING TO 40 KT...WITH ASCAT INDICATING 30 KT
MAX. ALSO BUOY 44037 OVER NERN GULF OF MAINE HAD 10 FT REPORT AT
17Z. OVER THE NEXT COUPLE DAYS MODELS ARE IN VERY GOOD AGREEMENT
OVER THE W ATLC. HIGH CONFIDENCE WITH PREVIOUSLY FORECAST W
GALES TONIGHT AND THU ERN NEW ENGL AND NERN MID ATLC WATERS AS
MODELS HAVE CONVERGED ON STRONGER SOLUTION WHICH GFS HAS
ADVERTISED FOR PAST FEW DAYS. EVEN THE TYPICALLY UNDERDONE UKMET
SFC WINDS ARE AS HIGH AS GALE. SECONDARY COLD FRONT SHOULD MOVE
OFFSHORE TONIGHT AND FURTHER ENHANCE COLD AIR ADVECTION TONIGHT
INTO THU. MODELS THEN INDICATE HIGH PRES RIDGE WILL BUILD OFF
COAST S OF HATTERAS THU NIGHT THROUGH FRI NIGHT AS SERIES OF LOW
PRES TROFS DROP SE OVER NEW ENGL WATERS. AM CONTINUING TO FAVOR
THE SLIGHTLY HIGHER GFS 30M WINDS IN COLD AIR ADVECTION THROUGH
THU NIGHT... THEN WILL TRANSITION TO 12Z GFS 10M WINDS FRI/FRI
NIGHT.

MODELS THEN CONTINUE TO HAVE DIFFICULTY AND EXHIBIT VERY LITTLE
RUN TO RUN CONSISTENCY WITH WEAK DVLPG COASTAL LOW(S) THIS
WEEKEND. OVER LAST COUPLE RUNS ECMWF AND NOT PARALLEL GFS HAVE
TRENDED SIGNIFICANTLY SLOWER. DETAIL DIFFERENCES AT SFC ARE NOT
THAT SURPRISING GIVEN MORE ZONAL FLOW AT UPPER LVLS WITH
MULTIPLE EMBEDDED SHRTWVS MOVING OFF THE COAST. FOR WIND GRIDS
WILL BE USING A 50/50 BLEND OF PAST TWO RUNS OF ECMWF WHICH WILL
RESULT IN LESS PROGRESSIVE SOLUTION THAN PREVIOUS GRIDS LATE SAT
THROUGH MON. MODELS COME INTO BETTER AGREEMENT WITH NEXT WEEK IN
SHOWING LARGE CLOSED UPPER LOW APPROACHING ERN US LATE TUE/WED.
WILL CONTINUE WITH MAX WINDS TO 25 KT OVER MOST ZONES SUN/MON.


AS MENTIONED ABOVE BUOY 44037 OVER NERN GULF OF MAINE HAD 10 FT
REPORT AT 17Z BUT HAS NOT REPORTED SINCE. WILL BUMP SIG WV HGTS
GULF OF MAINE BY 1 TO 2 FT TONIGHT. THEN 12Z MWW3 LOOKS
REASONABLE. WITH PREFERENCE FOR ECMWF BLEND SAT THROUGH MIDWEEK
WILL BE USING SIMILAR 50/50 BLEND OF PAST TWO ECMWF WAVE MDL
RUNS.

.EXTRATROPICAL STORM SURGE GUIDANCE...GIVEN OFFSHORE WINDS OVER
NEXT COUPLE DAYS BOTH 12Z ESTOFS AND 12Z ETSS SHOW A NEGATIVE
SURGE WITH ESTOFS IN -1 TO -1.5 FT RANGE FROM VA CAPES TO
MARTHAS VINEYARD TONIGHT THROUGH FRI. ETSS IS LESS NEGATIVE WITH
SURGE VALUES CLOSER TO -1 FT. A BLEND OF THESE TWO MODELS IS
LIKELY TO BE THE BEST APPROACH.

.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
.ANZ800...GULF OF MAINE...
     GALE TONIGHT INTO THU.
.ANZ805...GEORGES BANK WEST OF 68W...
     GALE TONIGHT INTO THU.
.ANZ900...GEORGES BANK EAST OF 68W...
     GALE TONIGHT INTO THU.
.ANZ810...SOUTH OF NEW ENGLAND...
     GALE TONIGHT INTO THU.

.NT2 MID ATLC WATERS...
.ANZ915...HUDSON CANYON TO THE GREAT SOUTH CHANNEL...
     GALE TONIGHT INTO THU.
.ANZ905...THE GREAT SOUTH CHANNEL TO THE HAGUE LINE...
     GALE TONIGHT INTO THU.
.ANZ910...EAST OF THE GREAT SOUTH CHANNEL AND SOUTH OF 39N...
     GALE THU.

$$

.FORECASTER CLARK. OCEAN PREDICTION CENTER.


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