Marine Interpretation Message
Issued by NWS

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000
AGNT40 KWNM 170214
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
1014 PM EDT WED APR 16 2014

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

STLT TRENDS AND NEW 00Z NCEP SFC ANAL SHOW FNT E OF OFSHR WTRS
SLOWING DOWN WITH SRN PART BCMG STNRY. NEAR TERM GRADIENTS IN NE
FLOW NW OF FNT AS SHOWN IN MDLS SPRT SUBGALE CONDS AS FNT AND HI
PRES RDG TO N SLOLY WKN THRU THU NIGHT. MDLS ARE IN GOOD AGRMT
THRU THU NIGHT...WITH 12Z/18Z GFS LOOKING RSNBL. GFS THEN MORE
QUICKLY MOVS LOW PRES ALG FNT NE ACRS FL VERSUS OTHER MDLS. 12Z
UKMET/GEM AND ECMWF SPRT SLOWER TRACK AND FARTHER W. PREVIOUS
SHIFT EVENTUALLY USED 12Z ECMWF FM 12Z FRI ON AS THIS MDL IS
SLOWER BUT NOT AS FAR W AS UK/EC. 12Z ECMWF IS CLOSE TO FINAL WPC
MED RNG GUIDANCE...BEGINNING TO LIFT LOW PRES OUT NR OUTER SRN NT2
WTRS BY DAY 5. IT BEARS WATCHING THE INCRG GRADIENTS OVR SRN WTRS
AS REINFORCING HIGH PRES FM CANADA BLDS DOWN INTO MID ATLC
WTRS...AS THESE SITUATIONS OF LOWS UNDERCUTTING HIGHS OFTEN
PRODUCE WRNGS. ECMWF DVLPS NMRS 30 KT BL WNDS WITH EVEN A 35 KT
SML AREA OUTER SRN WTRS ON SUN...BEFORE THE CNDN HIGH MOVS E AND
GRADIENT WKNS. FOR NOW WILL CAP WNDS AT 30 KT FOR NOW AS LOW LVLS
APPR MORE UNSTABLE TO THE N WHERE GRADIENTS ARE LESS.

SEAS...COMPARING MDLS WITH 00Z SEA STATE ANAL...12Z ECMWF WAM
APPRS BEST INITIALIZED OVR NT2 WTRS ESPCLY IN THE S...AND
THEREFORE REPOPULATED WITH THAT MDL THRU 12Z THU. MDLS BCM CLOSER
AFTER THAT AND USED 50/50 BLEND OF MULTIGRID WW3 WITH ECMWF OUT TO
12Z FRI AND THEN WITH ECMWF FAVORED...USED 12Z ECMWF WAM FRI AND
BYND.
-----------------------------------------------------------------
PREVIOUS DISCUSSION...

SFC ANALYSIS AND SATELLITE IMAGERY INDICATE COLD FRONT NOW MOSTLY
E OF THE OFFSHORE WATERS EXCEPT THE FAR E PORTION OF BALT CANYON
TO HAGUE WATERS. AN ASACT PASS FROM 1510Z INDICATED SEVERAL AREAS
OF NW GALES...ONE OVER THE W PORTION OF BALT TO HATTERAS CANYON
AND HATTERAS CANYON TO CAPE FEAR...WITH ANOTHER OVER SRN PORTION
OF BALT CANON TO HAGUE. THESE AREA WERE EMBEDDED IN A BROAD AREA
OF 25 TO 30 KT WINDS DEPICTED OVER MOST OF AREA.

THE 12Z MODELS AREA IN DECENT AGREEMENT THROUGH THE SHORT TERM
PERIOD...ROUGHLY FROM TONIGHT THROUGH 12Z FRI. FROM 12Z FRI AND
BEYOND...THE MODELS DIVERGE WITH THE GFS CONTINUING TO BE A CLEAR
OUTLIER. FOR THE SHORT TERM PERIOD...WILL ALLOW THE GALE WARNINGS
TO EXPIRE AS SCHEDULED WITH THE NEXT FCST ISSUANCE. STILL
EXPECTING WINDS TO REMAIN IN THE 20 TO 30 KT RANGE OVER THE NRN
NT2 WATERS OVERNIGHT BEFORE DIMINISHING THU. LOOKING AHEAD TO 12Z
FRI AND BEYOND...THE 12Z GFS HAS TRENDED CLOSER TO THE
ECMWF/UMKET/CMC...HOWEVER IT IS FURTHER E AND FASTER MOVING A LOW
ACROSS FLORIDA FRI NIGHT AND EARLY SAT THEN MOVING NE. AT THE
PRESENT TIME...AM FAVORING THE 12Z UKMET/CMC WHICH HAS A SLOWER
AND FURTHER W LOW TRACK. THESE ARE ALSO MORE IN LINE WITH THE
PREVIOUS 00Z ECMWF...ALTHOUGH THE LOW IS A BIT FURTHER N. IN
SUMMARY...WILL GO CLOSE TO THE 12Z GFS THROUGH 12Z FRI...THEN WILL
TREND TO THE 12Z UKMET FOR THE REMAINDER OF THE PERIOD. NO WARNING
HEADLINES WILL BE NEEDED THROUGH THE PERIOD.

.SEAS...THE LATEST SEA STATE ANALYSIS INDICATED THAT OBSERVED SEAS
WERE WITHIN A FT OF THE MWW3 FCST VALUES. WILL GO CLOSE TO THE
MWW3 THROUGH 12Z FRI. FOR THE REMAINDER OF THE PERIOD...WILL TREND
CLOSER TO THE ECMWF WAM WHICH AS MENTIONED IS MORE IN LINE WITH
THE UKMET/CMC.

.EXTRATROPICAL STORM SURGE GUIDANCE...N/A

.WARNINGS...PRELIMINARY. ANY CHANGES WILL BE COORDINATED THROUGH
AWIPS 12 PLANET CHAT OR BY TELEPHONE:

.NT1 NEW ENGLAND WATERS...
     NONE.

.NT2 MID ATLC WATERS...
     NONE.

$$

.FORECASTER BANCROFT/KOSIER. OCEAN PREDICTION CENTER.



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