Marine Interpretation Message
Issued by NWS

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AGNT40 KWNM 281304
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
904 AM EDT FRI AUG 28 2015

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

A QUIET PATTERN PERSISTS ACRS THE CSTL/OFSHR WTRS. A HIGH PRES
RIDGE NOSING OFSHR ACRS THE NRN WTRS IS MAINTAINING WINDS GRNLY IN
THE 5-10 KT RANGE ACRS THE NT1 AND NRN/CNTRL NT2 WTRS. S OF THE
RIDGE AND N OF STNRY FRONT SW-NE ACRS THE SRN NT2 WTRS A NELY
GRADIENT WITH MAX WINDS GNRLY IN THE 15-20 KT PERSISTS.

OVER THE SHORT TERM...THE LATEST MDLS FCST THE QUIET PATTERN TO
PERSIST. THE MDLS ALL FCST THE HIGH PRES RIDGE TO BUILD OFSHR ACRS
THE NRN WTRS MAINTAINING LITE WINDS. FURTHER S TO VARYING DEGREES
THE MDLS FCST A WEAK FRONTAL WAVE TO TRACK NE ALONG THE STNRY
FRONT ACRS THE SRN AND CNTRL NT2 WTRS THRU SAT NITE. A COMPROMISE
00Z GFS/ECMWF SOLUTION FOR THIS FRONTAL WAVE LOOKS RSNBL AND AS A
RESULT WULD CAP MAX ASCD WINDS IN THE 15-20 KT RANGE. THEREFORE
FOR NOW WL CONT TO USE THE PREVLY POPULATED 00Z GFS 10M BL WINDS
THRU THE SHORT TERM WITH JUST SM MINOR ADDITIONAL EDITS MAINLY IN
DEFERENCE TO THE 00Z ECMWF.

IN THE LONG RANGE...VS ITS PREV 00Z RUN...OVER THE NRN WTRS THE
06Z GFS REMAINS CONSISTENT IN FCSTG THE ONLY SIG WEATHER FEATURE
TO BE A WEAK COLD FRONT PUSHING S ACRS THE NT1 WTRS LATE MON/MON
NITE...THEN STALLING ACRS THE CNTRL NT2 WTRS LATE TUE/TUE NITE WHL
DSIPTG. OTHERWISE THE BIGGEST FCST PROBLEM LATE IN THE LONG RANGE
REMAINS THE FUTURE TRACK OF T.S. ERIKA...IF SHE STILL EXISTS BY
THEN. VS ITS PREV 00Z RUN...THE 06Z GFS NOW FCSTS ERIKA TO TRACK
FURTHER N MON/MON NITE...THEN DRIFT SLOWLY N INLAND INTO NRN
FLORIDA TUE/TUE NITE WITH ITS 02/06Z FCST POSITION NOW QUITE
CLOSE TO THE LATEST NHC 120 HR FCST PSN. THE 06Z GFDL AND 06Z HWRF
BOTH FCST SIGLY STRONGER CYCLONES TRACKING MR QUICKLY N TO JUST
OFSHR S CAROLINA OR INLAND NR THE S CAROLINA/GEORGIA BORDER...
RESPECTIVELY. WITH THE 00Z GFS/UKMET/ECMWF ALL BEING SIGLY FURTHER
W AT 120 HRS...AND DUE TO THE CURRENT MDL DISPARITY...WITH THE
06Z GFS CLOSE TO THEIR PREV FCST TRACK THEN WL NOT BE SURPRISED
IF NHC DOES NOT MAKE AND MAJOR CHNGS TO THEIR PREV FCST TRACK IN
THE NEXT ADVISORY. SO OF COURSE WL HV TO WAIT FOR THE NEXT HURCN
CONFERENCE CALL AND THE NEXT ADVSRY BEFORE MAKING ANY SIG CHNGS TO
PREV NT2 FCST.



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

THE 06Z SFC ANALYSIS INDICATED A COLD FRONT WELL E OF THE NRN
OFFSHORE WATERS...WITH STATIONARY FRONT EXTENDING ACROSS THE SRN
PORTION OF MID ATLANTIC WATERS. AN ASCAT PASS FROM LATE THU
EVENING INDICATED A SMALL AREA OF 20 KT WINDS OVER THE CENTRAL MID
ATLANTIC WATERS...OTHERWISE WINDS WERE LESS THAN 20 KT.

THE 00Z MODELS ARE IN VERY GOOD AGREEMENT DURING THE SHORT TERM
PERIOD...AND HAVE COME INTO SLIGHTLY BETTER AGREEMENT DURING THE
EXTENDED PERIOD AS WELL WITH EVENTUAL TRACK OF T.S. ERIKA. FOR
TODAY THROUGH THE WEEKEND AND INTO MON...THE MODELS ARE VERY
SIMILAR MAINTAINING STATIONARY FRONT IN THE SAME GENERAL VICINITY
AS HIGH PRES RIDGE BUILDS OFFSHORE OVER THE NT1 AND NRN NT2
WATERS. SEVERAL WEAK WAVES WILL MOVE NE AND E ALONG THE
FRONT...THOUGH WINDS WILL REMAIN UNDER 25 KT. THEN LOOKING AHEAD
TO THE LONGER RANGE...THE GFS AND CMC HAVE TRENDED FURTHER W WITH
THE TRACK OF ERIKA...AND THE GFS/ECMWF/UKMET ARE ACTUALLY NOW IN
DECENT AGREEMENT WITH A MORE W TRACK WITH ONLY MINIMAL EFFECTS
FOR THE SRN OFFSHORE WATERS TUE AND TUE NIGHT. THE OFFICIAL NHC
TRACK BRINGS ERIKA INLAND OVER S FLORIDA...THEN TURNS N. WILL
POPULATE USING THE GFS 10M WINDS THROUGH MAJORITY OF PERIOD THEN
USE TCM WINDS LATER MON INTO TUE NIGHT.

.SEAS...THE 06Z SEA STATE ANALYSIS INDICATED THAT OBSERVED SEAS
CONTINUE TO MATCH UP WELL WITH THE MWW3/ECMWF WAM. WILL POPULATE
THE WAVE GRIDS USING THE MWW3 THROUGH THE PERIOD.

.EXTRATROPICAL STORM SURGE GUIDANCE...N/A.


.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
     NONE.

.NT2 MID ATLC WATERS...
     NONE.

$$

.FORECASTER VUKITS/KOSIER. OCEAN PREDICTION CENTER.



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