Marine Interpretation Message
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000
AGNT40 KWNM 090118
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
818 PM EST MON FEB 8 2016

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

THE STRONG LOW PRES CENTER CONTS TO TRACK NEWD AND IS NOW S OF
NOVA SCOTIA. ASCD STORM FORCE WINDS SHULD NOW BE E OF THE OFSHR
WTRS WITH MAX WINDS ACRS THE ERN MOST NT1 AND NE MOST NT2 WTRS UP
TO 40 OR 45 KT. MAX SEAS ACRS THESE SAME WATERS ARE IN THE MID
20S...WHICH ARE STIL RUNNING HIGHER THAN FCST BY THE 18Z WAVEWATCH
III AND 12Z ECMWF WAM...THO THE WAM IS DOING BETTER. FURTHER
S...PER BUOY 41004...WINDS HV ALREADY INCRSD TO MARGINAL GALE
FORCE ACRS THE SW MOST NT2 WTRS AS AN INLAND SFC LOW AND COLD
FRONT ARE POISED TO MOV OFSHR.

OVER THE SHORT TERM...A VERY PROGRESSIVE AND ACTIVE PATTERN IS
FCST TO CONT BY ALL OF THE LATEST FCST MDLS. PER A CONSENSUS OF
THE MDLS...EXPECT WINDS ASCD WITH THE DEPARTING STORM TO DMNSH TO
SUBGALE THRUT THE WTRS BY EARLY TONITE. THEN OVERALL THE LATEST
MDLS ARE IN GNRLY GOOD AGRMT THAT THE NEXT DVLPG SFC LOW WL MOV
OFF THE MID ATLC COAST TONITE...INTENSIFY AS IT TRACKS NE ACRS THE
NERN NT2 WTRS TUE AND PULLS A STRONG COLD FRONT OFSHR...THEN MOVES
OFF TO THE NE TUE NITE. WITH THE 18Z GFS TRENDING SLIGHTLY
STRONGER THAN ITS PREV 12Z RUN...WHICH IS SPRTD BY THE 18Z GEFS
MEAN...STIL CANNOT COMPLETELY RULE OUT HURCN FORCE ASCD WINDS
DVLPG ACRS THE NT2 ZONES ANZ905 AND ANZ910 LATE TUE. BUT FOR NOW
WL CONT TO COMPROMISE WITH THE OTHER GLOBAL MDLS AND WL CONT TO
FCST ASCD STORM FORCE WINDS BY USING THE PREV MIX OF SMLR 12Z GFS
BL WINDS. THEN QUICKLY IN THE WAKE OF THIS DVLPG SFC LOW THE
18Z/12Z GFS AND 12Z UKMET/ECMWF ARE OVERALL IN GOOD AGRMT THAT
ANOTHER SFC LOW WL MOV OFF THE NRN MID ATLC COAST TUE NITE...TRACK
ENE NR 40N WED...THEN MOV OFF TO THE NE WED NITE WHICH WL MAINTAIN
A MOD TO STRONG WLY GRADIENT TO ITS S ACRS THE NT2 WTRS. SO AGAIN
WITH THE 18Z GFS RMNG VERY CONSISTENT...WL JUST MAKE SM MINOR
TWEAKS TO THE PREVLY POPULATED 12Z GFS WINDS...MAINLY IN DEFERENCE
TO THE 12Z ECMWF.

IN THE LONG RANGE...THE MOST SIG FCST PROBLEM DVLPS FRI NITE INTO
SAT NITE. IN GNRLY THE LASTEST GLOBAL MDLS CONVERGE TWDS A
SOLUTION OF A SERIES OF SFC LOWS MOVG OFSHR FRI NITE...
CONSOLIDATING INTO ONE SIG SFC LOW SAT...THEN PASSING E OF THE
OFSHR WTRS SAT NITE. THE FCST PROBLEM IS HOW THE MDLS GET TO THEIR
CONSOLIDATED SOLUTIONS. FOR NOW WITH NOT ANY SIG FCST
CONFIDENCE...WL FAVOR THE QUICKER 12Z ECMWF SOLUTION WHICH IS IN
LINE WITH THE LATEST WPC MEDIUM RANGE GUIDANCE. SO PLAN ON MAKING
SM GNRLY MINOR LONG RANGE CHNGS TO THE PREV OFSHR FCSTS.




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

14Z AND 15Z HIGH RESOLUTION ASCAT OVERPASSES CONFIRMED STORM
FORCE WINDS OVER OUTER MID ATLC ZONES N OF HATTERAS CANYON AND
ALSO S OF NEW ENGLAND WATERS AND GEORGES BANK. ASCAT SUGGESTS
THAT THE HIGHER 12Z GFS 30M WINDS INITIALIZED BEST. 12Z MODELS
IN GOOD AGREMEEMENT OVER THE NEAR TERM THAT HURRICANE FORCE LOW
WILL CONTINUE TO TRACK NE WITH THE MAXIMUM ASSOCIATED WINDS
SLOWLY WEAKENING. THEN WITH NEXT DEVELOPING LOW AND STRONG COLD
FRONT FORECAST TO MOVE OFF THE COAST NEAR THE VIRGINIA CAPES
TONIGHT... THE 12Z GFS HAS BACKED OFF THE HURRICANE FORCE WINDS
IT HAD ADVERTISED IN PREVIOUS RUNS. 12Z GFS AND 12Z ECMWF ARE
SLIGHTLY DEEPER THAN 12Z UKMET AND 12Z CANADIAN. WILL CONTINUE
TO FAVOR DEEPER SOLUTION AND OPT TO KEEP CONTINUITY WITH HIGHEST
WINDS TO 60 KT OVER OUTER MID ATLC WATERS TUE AFTERNOON. AS
WOULD BE EXPECTED UKMET AND CANADIAN ARE ALSO SE OF GFS/ECMWF
WITH SURFACE LOW TRACK. MODELS THEN INDICATE THAT IN RESPONSE TO
ANOTHER UPPER SHORTWAVE ROTATING THROUGH BASE OF LONG WAVE UPPER
TROUGH SHOULD SEE ANOTHER SFC LOW DEVELOP AND MOVE OFF THE
DELMARVA PENINSULA TUE NIGHT. GFS AND ECMWF ARE IN REASONABLE
AGREEMENT THIS LOW WILL ACCELERATE NE FOLLOWED BY ANOTHER LOW
AND COLD FRONT MOVING OFF THE NEW ENGLAND COAST WED NIGHT. WITH
STRONG HIGH PRES BUILDING IN BEHIND THE W TO NW GALES SHOULD
PERSIST THU INTO FRI. FOR WIND GRIDS USED A 50/50 BLEND OF 12Z
GFS 10M AND 30M WINDS WHICH WILL NOT RESULT IN MUCH CHANGE TO
PREVIOUS WARNINGS.

MODELS THEN DIVERGE LATE IN THE WEEK WITH ANOTHER POTENTIAL LOW
MOVING OFF THE MID ATLC COAST FRI/FRI NIGHT. 12Z ECMWF BACKED
OFF FROM ITS PREVIOUS SOLUTION WHICH FEATURED A RAPIDLY
DEVELOPING LOW JUST SE OF CAPE COD BY EARLY SAT. 12Z GFS TRENDED
FURTHER S WITH LOW FROM ITS PREVIOUS RUN AND ITS ASSOCIATED
WINDS LOOK A BIT SUSPECT. BASED ON THIS AND TO KEEP SOME
CONTINUITY USED  50/50 BLEND 12Z ECMWF AND PREVIOUS GRIDS FRI
THROUGH REMAINDER OF FORECAST PERIOD. BY SAT AND SAT NIGHT 12Z
MODELS ARE ACTUALLY IN BETTER AGREEMENT THAN 24 HOURS PRIOR AS
ALL SHOW FAIRLY WIDESPREAD NW GALES OVER WATERS. GIVEN THAT THIS
AIRMASS WILL BE COLDEST OF THE WINTER AND POSSIBLY OF PAST
SEVERAL WINTERS BOOSTED BLENDED WINDS BY 10 PERCENT GIVEN
STRENGTH OF COLD AIR ADVECTION BEGINNING SAT. HAVE ABOVE AVERAGE
FORECAST CONFIDENCE WITH THESE WEEKEND GALES.

BUOY OBSERVATIONS OVER NEW ENGLAND WATERS FOR PAST FEW HOURS ARE
INDICATING THAT BOTH 12Z WAVEWATCH III AND TO A LESSER EXTENT
THE 12Z ECMWF WAM ARE ABOUT 20 PERCENT UNDERDONE THIS AFTERNOON.
USED THE HIGHER ECMWF WAM AS A START FOR TONIGHT AND BOOSTED
THESE GRIDS UP FROM THERE. TRANSITIONED TO 12Z WW3 TUE/TUE NIGHT
BEFORE USING 50/50 BLEND OF 12Z ECMWF WAM AND 12Z WW3 WED ONWARD.

.EXTRATROPICAL STORM SURGE GUIDANCE...THE HIGHER ESTOFS APPEARS
TO INITIALLY HAVE A BETTER HANDLE THAN THE ETSS WITH STORM SURGE
AFFECTING NEW ENGLAND COAST AND NORTHERN MID ATLC COAST
CURRENTLY. THEN AS IS OFTEN TIMES THE CASE THE ESTOFS IS LIKELY
OVERDONE WITH NEGATIVE SURGE IN STRONG OFFSHORE FLOW TONIGHT
THROUGH THU OFF SE US COAST AND CENTRAL/NRN MID ATLC AND NEW
ENGLAND WED INTO FRI.


.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
.ANZ800...GULF OF MAINE...
     GALE TONIGHT.
     GALE POSSIBLE THU NIGHT.
     GALE POSSIBLE SAT NIGHT.
.ANZ805...GEORGES BANK WEST OF 68W...
     GALE TUE.
     GALE POSSIBLE THU INTO THU NIGHT.
     GALE POSSIBLE SAT INTO SAT NIGHT.
.ANZ900...GEORGES BANK EAST OF 68W...
     GALE TUE INTO TUE NIGHT.
     GALE POSSIBLE THU NIGHT.
     GALE POSSIBLE SAT NIGHT.
.ANZ810...SOUTH OF NEW ENGLAND...
     GALE TUE.
     GALE POSSIBLE THU INTO THU NIGHT.
     GALE POSSIBLE SAT NIGHT.
.ANZ815...SOUTH OF LONG ISLAND...
     GALE POSSIBLE THU INTO THU NIGHT.
     GALE POSSIBLE SAT INTO SAT NIGHT.

.NT2 MID ATLC WATERS...
.ANZ820...HUDSON CANYON TO BALTIMORE CANYON...
     GALE POSSIBLE THU INTO THU NIGHT.
     GALE POSSIBLE SAT INTO SAT NIGHT.
.ANZ915...HUDSON CANYON TO THE GREAT SOUTH CHANNEL...
     GALE TUE INTO WED.
     GALE POSSIBLE THU INTO THU NIGHT.
     GALE POSSIBLE SAT INTO SAT NIGHT.
.ANZ920...BALTIMORE CANYON TO THE GREAT SOUTH CHANNEL...
     STORM TUE.
     GALE TUE NIGHT INTO WED.
     GALE POSSIBLE WED NIGHT INTO THU NIGHT.
     GALE POSSIBLE SAT INTO SAT NIGHT.
.ANZ905...THE GREAT SOUTH CHANNEL TO THE HAGUE LINE...
     GALE TONIGHT.
     STORM TUE INTO TUE NIGHT.
     GALE WED.
     GALE POSSIBLE THU INTO FRI.
     GALE POSSIBLE SAT NIGHT.
.ANZ910...EAST OF THE GREAT SOUTH CHANNEL AND SOUTH OF 39N...
     GALE TONIGHT.
     STORM TUE INTO TUE NIGHT.
     GALE WED.
     GALE POSSIBLE THU INTO THU NIGHT.
     GALE POSSIBLE SAT NIGHT.
.ANZ825...INNER WATERS FROM BALTIMORE CANYON TO CAPE CHARLES LIGHT...
     GALE POSSIBLE THU INTO THU NIGHT.
     GALE POSSIBLE SAT NIGHT.
.ANZ828...INNER WATERS FROM CAPE CHARLES LIGHT TO CURRITUCK BEACH LIGHT...
     GALE TUE.
     GALE POSSIBLE SAT NIGHT.
.ANZ925...OUTER WATERS FROM BALTIMORE CANYON TO HATTERAS CANYON...
     GALE TONIGHT.
     STORM TUE.
     GALE TUE NIGHT INTO WED.
     GALE POSSIBLE WED NIGHT INTO SAT NIGHT.
.ANZ830...INNER WATERS FROM CURRITUCK BEACH LIGHT TO CAPE HATTERAS...
     GALE TONIGHT INTO TUE NIGHT.
     GALE POSSIBLE SAT NIGHT.
.ANZ833...INNER WATERS FROM CAPE HATTERAS TO CAPE FEAR...
     GALE TONIGHT INTO WED.
.ANZ930...OUTER WATERS FROM HATTERAS CANYON TO CAPE FEAR...
     STORM TONIGHT INTO TUE.
     GALE TUE NIGHT INTO WED.
     GALE POSSIBLE WED NIGHT.
     GALE POSSIBLE FRI INTO FRI NIGHT.
     GALE POSSIBLE SAT NIGHT.
.ANZ835...INNER WATERS FROM CAPE FEAR TO 31N...
     GALE TONIGHT INTO WED.
     GALE POSSIBLE FRI NIGHT.
.ANZ935...OUTER WATERS FROM CAPE FEAR TO 31N...
     GALE TONIGHT.
     STORM TUE.
     GALE TUE NIGHT INTO WED.
     GALE POSSIBLE WED NIGHT.
     GALE POSSIBLE FRI NIGHT INTO SAT.

$$

.FORECASTER VUKITS/CLARK. OCEAN PREDICTION CENTER.


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