Marine Interpretation Message
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000
AGNT40 KWNM 281350
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
950 AM EDT TUE APR 28 2015

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

LOW PRES WAS ABT 400 NM E OF CAPE COD AT 8 AM AND WL MOV E AND NE
TDA AND TNGT WHILE INTENSIFYING. WITHIN ABT 300 NM OF THE WRN
SEMICIRCLE MDL GUID HAS WINDS TO 35 KT. BUOY OBS IN THIS REGION
ARE SHOWING ABT 25 TO 30 KT IN THE PAST SVRL HRS. THERE WAS A
SHIP OBS AT 8 AM JUST E OF THE NRN MID ATLC OFFSHR WTRS ZONE 910
WHICH HAD 35 KT WHICH FIT WELL WITH 30M GFS WINDS. MDLS ARE IN
GOOD AGRMT WITH THE LOW PRES PASSING E AND NE TDA THRU WED. THERE
ARE DIFFS WITH THE DVLPG LOW PRES THAT MOVS NE OFF THE SE COASTLN
LATE WED AND WED NGT. THE GFS IS STGST WITH THE DVLPMT LIFTING
THE LOW PRES FM THE FL COAST THEN MOVG N ALG THE SE COAST AND
BECOMG STGR AS UPR SHRTWV MOVS IN FM THE NW. THE ECMWF IS FURTHER
E WITH THE DVLPMT AND LIFTS THE STRENGTHENING LOW ALG THE ERN
AREAS OF THE MID ATLC WTRS. THE UKMET TRACKS THE LOW PRES ALG THE
SRN WTRS OF MID ATLC WHICH PASSES E OF THE AREA LATE THU. THE GEM
ALSO SUPPORTS THE UKMET WITH A TRACK ALG THE SRN WTRS...BUT IT
ALSO DVLPS ANOTHER LOW IN RESPONSE TO UPR SHRTWV ALG E COAST NR
THE OUTER BANKS OF NC. ATTM THE GRIDS FAVOR THE ECMWF WITH THE LOW
PRES DVLPMT AND WL STAY WITH THE 00Z ECMWF FOR NOW. AM NOT HIGHLY
CONFDT WITH THE ECMWF WITH ITS SLN AND WUD PREFER A MORE WWD
TRACK. FOR THE UPDATE WL STAY WITH ECMWF. WL AWAIT THE 12Z
NUMERICAL MDL GUID BEFORE MAKING ANY CHANGES LATER THIS AFTN.

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

SUMMARY...LOW PRES CNTRD JUST E OF THE NE NT2 WTRS WILL INTENSIFY
AS IT DRIFTS E TODAY AND TONITE...THEN ACCELERATE OFF TO THE E
WED. A HI PRES RIDGE WILL BUILD SE OVER THE NT2 WTRS TODAY...THEN
PASS E ACROSS THE NT2 AREA TONITE AND WED. ANOTHER RIDGE WILL
BUILD OVER THE NT1 WTRS WED INTO THU...THEN WILL WEAKEN AND RECEDE
TO THE N THU NITE INTO FRI. DVLPG LOW PRES WILL MOVE E INTO THE SW
NT2 WTRS LATE WED INTO WED NITE...INTENSIFY AS IT TRACKS NE ACROSS
THE CNTRL NT2 WTRS THU INTO FRI...THEN PASS E OF THE NRN NT2 WTRS
FRI NITE INTO SAT. THE LOW WILL MOVE WELL E OF THE REGION LATE
SAT AND SAT NITE AS ANOTHER RIDGE BUILDS E OVER THE OFSHR AREAS.

MODELS...THE 00Z MED RNG MDLS ARE IN GUD OVERALL AGREEMNT ACROSS
THE OFSHR WTRS INTO EARLY WED...SO THE REPRESENTATIVE 00Z GFS 30M
SOLN WILL BE USED TO POPULATE THE WIND GRIDS FOR THIS TIMEFRAME.
THE 00Z MED RNG MDLS ARE NOT IN GUD AGREEMNT FOR THE LATER WED
THRU SAT NITE PRD. THE GFS HAS NOT BEEN SHOWING GUD RUN TO RUN
CONSISTENCY...AND THE 00Z GFS IS NOT VRY WELL SUPPORTED BY THE 00Z
GEFS MEAN. 00Z ECMWF IS THE PREFERRED MDL FOR LATER WED THRU SAT
NITE...BECAUSE IT HAS BEEN SHOWING THE BEST RUN TO RUN CONSISTENCY
AND ALSO SINCE IT HAS STG SUPPORT FROM THE LATEST WPC MED RNG
FCSTR GUIDANCE. 00Z ECMWF WINDS WILL BE BOOSTED UP BY 15 PERCENT
SO THEY MATCH UP BETTER WITH CNTRL PRES OF THE DVLPG LOW. AM NOT
PLANNING TO MAKE ANY SIGNIF CHANGES TO THE CURRENT FCST TREND.

SEAS...WILL POPULATE THE SEA HT GRIDS USING A 50/50 BLEND OF 00Z
WNA VERSION OF WAVEWATCH III/ECMWF WAM FOR TODAY INTO EARLY
WED...THEN USE JUST THE 00Z ECMWF WAM FOR LATER WED THRU SAT
NITE. 00Z WNA WAVEWATCH III MDL LOOKS TOO SLOW TO BUILD UP THE
SEAS WITH THE DVLPG LOW ON THU THRU FRI...AND THE PREFERRED 00Z
ECMWF WAM BUILDS UP THE SEAS MORE QUICKLY THAN THE WAVEWATCH III.

.EXTRATROPICAL STORM SURGE GUIDANCE...ESTOFS AND ETSS HAVE BEEN
SHOWING A POS SURGE IN THE 1.0 TO 1.5 FT RANGE ALG THE CAROLINA
COAST FOR WED NITE INTO THU...WHICH CLD BE UNDERDONE GIVEN STG E
TO NE FLOW FCST FOR THAT AREA BY ECMWF/UKMET MDLS.


.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
.ANZ800...GULF OF MAINE...
     GALE TONIGHT.
.ANZ805...GEORGES BANK WEST OF 68W...
     GALE TONIGHT.
     GALE POSSIBLE FRI NIGHT.
.ANZ900...GEORGES BANK EAST OF 68W...
     GALE TODAY INTO TONIGHT.
     GALE POSSIBLE FRI NIGHT INTO SAT.

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

$$

.FORECASTER ROWLAND/SCOVIL. OCEAN PREDICTION CENTER.


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