Marine Interpretation Message
Issued by NWS

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000
AGNT40 KWNM 100109
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
809 PM EST TUE FEB 9 2016

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

AS THE DVLPG LOW PRES CENTER NOW E OF GEORGES BANK CONTS OFF TO
THE NE SUSPECT THAT ANY ASCD GALES HV NOW BCM LIMITED TO THE FAR
NE NT2 WTRS. MAX ASCD SEAS OVER THESE WTRS ARE LKLY NR 20 FT WHICH
ARE IN BTWN WHAT THE LOWER 18Z WAVEWATCH III AND HIGHER 12Z ECMWF
WAM MDLS HV AT THE MOMENT. ELSWHR PER RECENT SFC/BUOY OBS S OF THE
ASCD COLD FRONT WLY GALES ARE ALSO PRESENT OVER THE SRN NT2 WTRS.

OVER THE SHORT TERM...DUE TO THE SHORT WAVELENGTH BTWN THEIR ASCD
UPR S/W TROFS...THE LATEST MDLS CONT TO HV SM TRACK AND TIMING
DIFFERENCES IN RGRDS TO A SERIES OF ASCD SFC LOWS FCST TO DVLP AND
TRACK ENE ACRS THE NRN MOST NT2 AND SRN NT1 WTRS TONITE INTO WED.
THEN WED NITE INTO THU NITE IN RESPONSE TO A FINAL UPR S/W TROF
EXPECTED TO PASS E ACRS THE NRN WTRS THE MDLS GNRLY AGREE THAT A
FINAL ASCD SFC LOW WL CROSS THE NRN MOST NT1 WTRS WED NITE...THEN
CONT OFF TO THE E THU/THU NITE. THE END RESULT OF THE SFC LOWS
CROSSING THE AREA WL BE FOR THE CURRENT MOD TO STRONG WLY GRADIENT
TO GRADLY SHIFT NWD TONITE INTO THU NITE...WITH ANY ASCD GALES
BCMG LIMITED TO THE SE MOST NT1 AND NE MOST NT2 WTRS BY THU NITE.
PER THE LATEST MDLS HV LOW FCST CONFIDENCE IN THESE GALES
EXPANDING N INTO THE GULF OF MAINE WTRS LATE THU INTO THU NITE.
BUT FOR NOW WITH THE 18Z GFS RMNG CONSISTENT VS ITS PREV RUNS IN
FCSTG THESE GALES WL LEAVE THEM IN PLACE FOR NOW AND THEN SEE IF
THE 00Z MDLS LATER DICTATE OTHERWISE. SO OTHERWISE PLAN ON JUST
MAKING SM MINOR EDITS TO THE PREV USED FCST WINDS MAINLY IN
DEFERENCE TO THE 18Z GFS AND 12Z ECMWF.

IN THE LONG RANGE...VS ITS PREV 12Z RUN...THE 18Z GFS HAS NOW
TRENDED SMWHT DEEPER WITH ITS DVLPG SFC LOW FCST TO TRACK NE ACRS
THE SRN AND CNTRL NT2 WTRS FRI INTO FRI NITE WHICH IS MR IN LINE
WITH THE 12Z ECMWF. SO SINCE THE 18Z GEFS MEAN ALSO SPRTS THE 18Z
GFS...WL BEEF UP THE PREVLY POPULATED WINDS...MAINLY ACRS THE
OUTERMOST NT2 WTRS. THEN SAT INTO SUN...THO THE LATEST GLOBAL MDLS
DIFFER IN THEIR EXACT FCST TRACKS AND STRENGTHS OF MULTIPLE SFC
LOWS FCST TO DVLP E OF THE AREA...THEY ALL GNRLY FCST A SMLRLY
STRONG NNWLY GRADIENT WITH WDSPRD GALES TO DVLP THRUT MUCH OF THE
WTRS. THEREFORE WITH THE 18Z GFS RMNG CONSISTENT...WL CONT WITH
THE PREVLY POPULATED WINDS...WITH SM MINOR ADDITIONAL EDITS IN
DEFERENCE TO THE 12Z UKMET/ECMWF ACRS THE NT1 WTRS...WHICH WL
RESULT IN ADDING THE GULF OF MAINE WTRS TO THE PREVLY FCSTD PSBL
GALES ON SAT NITE INTO SUN. SO OTHERWISE NO MAJOR LONG RANGE CHNGS
ARE PLANNED TO THE PREV OFSHR FCSTS.




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

1430Z AND 1520Z HIGH RESOLUTION ASCAT OVERPASSES CONFIRMED W
GALES OFFSHORE S OF CAPE LOOKOUT. HOWEVER THIS MORNINGS PASSES
MISSED OUTER NT2 WATERS WHERE HIGHEST WINDS ASSOCIATED WITH
DEVELOPING LOW WERE OCCURRING. BOTH THE 12Z GFS AND 12Z ECMWF
ARE INITIALIZING TWO SURFACE LOWS OVER SOUTHEASTERN EDGE OF
OUTER ZONES ANZ920 AND ANZ910. BASED ON THE ESTIMATED LOW
POSITIONS FROM THE GOES 1 MIN SUPER RAPID SCAN IMAGERY
TODAY...IT APPEARS THAT THE 12Z ECMWF HAS A BETTER 18Z POSITION
AT LEAST WITH SECOND CENTER INVOF 37N70W AT 18Z. 12Z GFS IS
ABOUT 1 TO 2 DEGREES NE OF ECMWF POSITION. 12Z MODELS ARE IN
GOOD AGREEMENT THAT THESE LOWS WILL ACCELERATE NE THIS AFTERNOON
AND EVENING. GIVEN ITS BETTER INITIAL POSITION(S) WILL USE 12Z
ECMWF FOR NEAR TERM WIND GRIDS. WILL HOWEVER BOOST THESE WINDS
SO THEY ARE MORE IN LINE WITH STRONGER 12Z GFS 30M WINDS. THERE
REMAINS SOME POTENTIAL THAT WINDS OVER SE QUADRANT OF SECOND LOW
WILL REACH HURRICANE FORCE OVER NEXT SEVERAL HOURS BUT THESE
WINDS WOULD BE E AND SE OF OUTER OFFSHORE WATERS.

THEN TONIGHT THROUGH WED NIGHT MODELS ARE IN GENERAL AGREEMENT
THAT A SERIES OF LOW WILL DEVELOP AND TRACK E ACROSS THE
NORTHERN MID ATLC AND SOUTHERN NEW ENGLAND WATERS. 12Z ECMWF AND
UKMET ARE SIMILAR TO PREVIOUS RUNS OF GFS IN LIMITING GALES TO
MID ATLC WATERS WED AND WED NIGHT. 12Z GFS TRACKS A DEVELOPING
LOW FURHTER N INTO NEW ENGLAND WATERS ALONG WITH ASSOCIATED
MARGINAL GALES. WILL NOT BE MAKING CHANGES TO WED/WED NIGHT WIND
GRIDS AS THEY ARE STRONGLY SUPPORTED BY LATEST 12Z ECMWF/UKMET.
W TO NW GALES SHOULD PERSIST THROUGH THU NIGHT WHILE SHIFTING
NORTHWARD THROUGH OFFSHORE WATERS AS LOW PRES CONSOLIDATES E OF
NEW ENGLAND WATERS. 12Z ECMWF HAS THEN BECOME IN LINE WITH GFS
AND UKMET AND NOW MOVES NEXT DEVELOPING LOW OFF THE COAST S OF
CAPE FEAR FRI. GFS STILL APPEARS TOO STRONG WITH WINDS FRI NIGHT
BUT BASED ON 12Z ECMWF WILL INTRODUCE SOME GALES OVER OUTER
WATERS S OF HATTERAS CANYON FRI NIGHT AS LOW TRACKS NE.
POPULATED WITH 12Z GFS 10M WINDS FRI AND FRI NIGHT TRIMMED
HIGHEST WINDS BY ABOUT 20 PERCENT OR SO. 12Z MODELS ALL SUGGEST
THAT FAIRLY WIDESPREAD GALES WILL DEVELOP AGAIN OFFSHORE SAT IN
SOME OF STRONGEST COLD AIR ADVECTION OF THIS WINTER SEASON. TO
ACCOUNT FOR SOME MINOR DIFFERENCES BETWEEN MODELS USED A 50/50
BLEND OF GFS 30M AND ECMWF WINDS...THEN ADJUSTED UP BY 5 TO 10
PERCENT. THE STRONG HIGH PRES RIDGE SHOULD REACH THE MID ATLC
AND NEW ENGLAND COASTS LATE SUN NIGHT...WITH DIMINISHING
WINDS/SEAS SUN AND SUN NIGHT.
WAVEWATCH III AND ECMWF WAM ARE DOING A MUCH BETTER JOB WITH
OFFSHORE AND COASTAL WAVE HEIGHTS THIS AFTERNOON THAN HAS BEEN
THE CASE OVER THE LAST 24 TO 36 HOURS. HOWEVER GUIDANCE IS STILL
SEVERAL FT UNDERDONE OVER NT1 WATERS...MAINLY THE GULF OF MAINE
AND GEORGES BANK. HAD TO MAKE MAJOR ADJUSTMENTS TO HIGHER 12Z
ECMWF WAM THROUGH THE NEAR TERM. THEN USED A 50/50 BLEND OF 12Z
WW3 AND 12Z ECMWF WAM THROUGH THE REMAINDER OF THE FORECAST
PERIOD.

.EXTRATROPICAL STORM SURGE GUIDANCE...AS THE STRONG OFFHSORE WLY
GRADIENT IS FCST BY THE GFS TO SPREAD NWD...SMLR TO ITS PREV
RESPECTIVE RUNS THE 12Z ESTOFS CONTS TO FCST A HIGHER NEGATIVE
SURGE TO DVLP FM THE SE COAST NWD UP THE COAST TODAY INTO FRI
THAN FCST BY THE 12Z ETSS...WHICH IS LKLY OVERDONE. CURRENTLY
WATER LEVEL ANOMALIES ARE GENERALLY RUNNING +1 TO +2 FT FROM SC
COAST NWD BUT THIS IS MOSTLY DUE TO HIGH ASTRONOMICAL TIDES.


.WARNINGS...PRELIMINARY.

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

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

$$

.FORECASTER VUKITS/CLARK. OCEAN PREDICTION CENTER.


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