Marine Interpretation Message
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
AGNT40 KWNM 220643
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
243 AM EDT FRI MAY 22 2015

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

OVER THE SHORT TERM...THE NEW 00Z MDLS REMAIN CONSISTENT AND IN
EXCELLENT AGRMT THAT THE DVLPG SFC LOW NOW NR 37N72W WL CONT TO
TRACK NE ACRS THE NE NT2 WTRS THIS MORNING...THEN ACCELERATE OFF
TO THE NE LATER TODAY. OVERALL BLV THE WELL SPRTD 00Z GFS SOLUTION
LOOKS REPRESENTATIVE FOR THIS SYSTEM (THE 00Z ECMWF LOOKS A LTL
TOO WEAK THRUT THE SHORT TERM) AND AS A RESULT SMLR TO THE PREV
OFSHR FCST PACKAGE WL START THE TODAY FCST PERIOD WITH HIGH
CONFIDENCE GALES ACRS THE NE NT2 AND EXTREME SE MOST NT1
WTRS...BCMG SUBGALE BY LATE THIS AFTERNOON. THEN THE 00Z MDLS
SHARE SMLR FCST TIMING FOR A COLD FRONT TO PUSH SE ACRS THE NT1
WTRS TONITE...THE NRN/CNTRL NT2 WTRS SAT...THEN DSIPT ACRS THE SRN
NT2 WTRS SAT NITE. THE BIGGEST FCST CHALLENGE FOR THIS FROPA IS
WHETHER MARGINAL POSTFRONTAL GALES WL DVLP BRIEFLY ACRS THE GULF
OF MAINE EARLY SAT. SMLR TO THEIR PREV RESPECTIVE RUNS...THE 00Z
NAM/GFS/GEM ALL FCST A BRIEF PD OF POSTFRONTAL GALE FORCE BL WINDS
OVER THESE WTRS. BASED ALSO ON THE MOD STRONG COLD AIR ADVECTION
FCST WITH THIS FROPA...WL GO AHEAD AND CONT WITH THE PREVLY FCSTD
LOWER CONFIDENCE MARGINAL GALES ACRS THE GULF OF MAINE FOR EARLY
SAT. SO AS WAS DONE WITH THE PAST SVRL FCSTS...PLAN ON POPULATING
OUR SHORT TERM FCST WIND GRIDS WITH THE 00Z GFS 30M BL WINDS FOR
TODAY THRU SAT...WITH SM ADDITIONAL MINOR EDITS MAINLY IN
DEFERENCE TO THE 00Z NAM...THEN WL TRANSITION TO THE 00Z GFS 10M
BL WINDS ON SAT NITE.

IN THE LONG RANGE...THE 00Z MDLS ARE IN GOOD AGRMT THAT A QUIET
WX PATTERN WL DVLP THRUT THE WTRS. IN RESPONSE TO AN UPR RIDGE
FCST TO BUILD TWDS THE E COAST SUN INTO MON NITE...THEN PERSIST
TUE/TUE NITE ALL OF THE 00Z MDLS FCST ASCD SFC HIGH PRES TO BLD IN
BHND THE COLD FRONT SAT/SAT NITE...THEN DVLP AND MAINTAIN A W-E
RIDGE ACRS THE CNTRL NT2 WTRS SUN THRU TUE NITE WITH LITE WINDS
PERSISTING IN ITS VCNTY. IN THE SWLY GRADIENT THAT WL DVLP N OF
THIS RIDGE ACRS THE NT1 AND NRN NT2 WTRS...ALONG WITH A WEAK WARM
FROPA MON NITE INTO TUE NITE...THE 00Z MDLS CONT TO VARY SMWHT IN
THEIR FCST STRENGTHS OF THIS GRADIENT. FOR NOW THE 00Z GFS
SOLUTION (WITH MAX ASCD WINDS HOLDING IN THE 20-25 KT RANGE) LOOKS
LK A RSNBL COMPROMISE FOR THIS GRADIENT BTWN THE STRONGER 00Z GEM
AND WEAKER 00Z UKMET/ECMWF SOLUTIONS. SO PLAN ON CONTG TO POPULATE
OUR LONG RANGE FCST WIND GRIDS WITH THE 00Z GFS 10M BL WINDS WHICH
WL RESULT IN ONLY MINIMAL CHNDS TO THE PREV OFSHR FCSTS.

.SEAS...OVER THE NT2 WTRS THE 00Z WAVEWATCH III HAS INITIALIZED
TOO LOW WITH THE DVLPG SFC LOW. THEREFORE WL USE A 50/50 BLEND OF
THE 00Z WAVEWATCH III WITH THE HIGHER 00Z ECMWF WAM FCST SEAS FOR
TODAY THRU SUN NITE. THEN LATER PREFER THE SMWHT LOWER SEAS FCST
BY THE 00Z WAVEWATCH III VS THE HIGHER 00Z ECMWF WAM ACRS THE NRN
WTRS IN THE SWLY GRADIENT. SO WL THEN TRANSITION TO POPULATING
WITH ALL 00Z WAVEWATCH III MON INTO TUE NITE.

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

.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
.ANZ800...GULF OF MAINE...
     GALE SAT.
.ANZ900...GEORGES BANK EAST OF 68W...
     GALE TODAY.

.NT2 MID ATLC WATERS...
.ANZ820...HUDSON CANYON TO BALTIMORE CANYON...
     GALE EARLY TODAY.
.ANZ915...HUDSON CANYON TO THE GREAT SOUTH CHANNEL...
     GALE EARLY TODAY INTO TODAY.
.ANZ920...BALTIMORE CANYON TO THE GREAT SOUTH CHANNEL...
     GALE EARLY TODAY INTO TODAY.
.ANZ905...THE GREAT SOUTH CHANNEL TO THE HAGUE LINE...
     GALE TODAY.
.ANZ910...EAST OF THE GREAT SOUTH CHANNEL AND SOUTH OF 39N...
     GALE TODAY.
.ANZ925...OUTER WATERS FROM BALTIMORE CANYON TO HATTERAS CANYON...
     GALE EARLY TODAY.

$$

.FORECASTER VUKITS. OCEAN PREDICTION CENTER.


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.