Marine Interpretation Message
Issued by NWS

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AGPN40 KWNM 111424
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
624 AM PST THU FEB 11 2016

.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT
.WEATHER FOR THE NORTH PACIFIC N OF 30N AND E OF 150W.

THE SAT IMG SHOW THAT MOST OF THE CLDS ARE OVR THE NRN AND CNTRL
WTRS WITH LIGHTNG STRIKES WELL W OF THE REGION. THE RADAR HAS NO
INDC OF TSTMS OVR THE REGION. THE SREF HAS LESS THAN 5 PERCENT
CHNCE OF TSTMS IN THE SHORT TERM. AT 12Z HGH PRES 1023 MB JUST W
OF THE SRN WTRS HAS RIDGE ACRS THE SRN WTRS. AN AREA OF LOW PRES
WITH SVRL CNTRS TO THE NW OF THE REGION WITH A WRM FRNT NOW ACRS
THE OREG WTRS. THE PRES GRDNT IS FAIRLY RELAXED OVR THE SRN WTRS
BUT TIGHT OVR THE NRN WTRS WHERE THE MAX OBSVD WINDS ARE IN THE
GALE FORCE. THE LAST ASCAT PASS IS DESCRIBED BELOW. THE HGHST SEAS
ARE OVR THE N-WRN WTRS WITH PEAK TO 19 FT. SEAS RANGE BTWN 9 AND
18 FT OVR THE NRN WTRS AND THEY RANGE BTWN 4 AND 8 FT ELSEWHERE
WITH SMALLEST SEAS OVR THE FAR S. THE NWW3 MULTI GRID WV MDL FITS
VERY WELL WITH THE OBSVD SEAS PATTERN AND HAS BEEN QUITE CONSSTNT
IN TE PREVIOUS RUNS. NWW3 IS ALSO CLOSE TO THE THE ECMWFWV AND SO
WILL CONTINUE WITH NWW3 GDNC FOR SEAS.

AN UPPRLVL RIDGE STILL LINGERS JUST E OF THE REGION WHILE SOME
ENERGY IS EMBBD IN AN UPPRLVL LOW NW OF THE REGION BUT SE OF THE
ALEUTIAN ISLANDS. IN THE SHORT TERM SOME OF THE ENRGY TO THE NW
WILL CONTINUE TO IMPACT THE NRN WTRS AS THEY SHIFT E. THE UPPRLVL
RIDGE WILL START TO WEAKEN AND ALLOW MORE ENRGY TO DIP FARTHER S
BUT THE MJR IMPACT ON WINDS WILL STILL BE CONFINED TO THE NRN
WTRS. LATER IN THE XTND PRD THE UPPRLVL RIDGE WILL STRENGTHEN
AGAIN AND KEEP WIPE OUT THE ENRGY OVR THE NRN WTRS THAT WILL
RESULT IN WINDS DIMINISHING TO BELOW GALE FORCE OVR THGE NRN WTRS.
MOST OF THE SRN WTRS WILL BE DOMINATED BY THE RIDGE AND THAT WILL
KEEP WINDS BELOW GALE FORCE THRESHOLD THRU THE FRCST PRD.

THE MDLS HAVE INITAILIZE WELL AND THEY ALL AGREE ON THE HGH PRES
REMAINING NEARLY STNRY NR THE SRN WTRS. THE MDLS ALSO AGRE WELL IN
THE SHORT TERM BUT SOME MNR DIFFS IN THE XTNDD PRD ON THE TIMING
OF THE SERIES OF FRNTS THAT WILL PASS OVR THE NRN WTRS. OTHERWISE
EVEN WITH THOSE SMALL DIFFS THE GENERAL YSNOP PATTERN REMAINS THE
SAME AND SO WILL JUST CONTINUE USE THE GFS AS MAIN GDNC. IN THE
SHORT TERM HGH PRES WILL MAINTAIN A RIDGE OVR THE SRN WTRS WHILE A
SERIES OF WEAK FRONTS WILL MOVE INTO THE NRN WTRS WHERE THEY WILL
DISPT. WILL KEEP GALES IN THE NRN WTRS INTO TONIGHT AND AGAIN FRI
NIGHT INTO EARLY SAT.

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

SHORT TERM...THE LATEST ASCAT AND ASCAT-B PASSES INDICATED A HIGH
PRES RIDGE OVER CENTRAL CALIF OFF WTRS...WITH STRONGER WINDS W OF
THE NRN CALIF AND PZ5 WTRS EARLY THIS MORNING ASSOC WITH A RATHER
LARGE COMPLEX LOW PRES SYSTEM. LOW PRES WILL INTENSIFY W OF THE
PZ5 WTRS TODAY AND LIFT N WITH A DVLPG WARM FRONT CROSSING PZ5
WTRS LATER THIS MORNING AND AFTN. A PERIOD OF GALE FORCE WINDS
STILL APPEAR LKLY JUST AHEAD OF THE FRONT OVR WRN AND NRN PZ5
WTRS TODAY. THE GALES WILL LIFT N OF THE WTRS TONITE AS THE WARM
FRONT LIFTS N OF THE AREA...WITH A BRIEF PERIOD OF GALES PSBL
NEAR AN ASSOC COLD FRONT MOVG INTO NW WASH WTRS TONITE PER THE
00Z MDL GUID. CONFDC LVLS FOR THE GALES OCCURRING OVR PZ5 WTRS
TODAY IS NEAR TO ABV AVERAGE...AND NEAR AVERAGE FOR TONITE OVR NW
WASH WTRS. THE HIGH PRES RIDGE OVR CENTRAL CAL OFF WTRS TODAY
WILL EXPAND OVR THE REGION TONITE INTO EARLY SAT WITH A LOW PRES
TROF DVLPG ALONG THE CALIF COAST. FOR THE MOST PART WE WILL
REMAIN CLOSEST TO THE 00Z GFS 30M WINDS FOR THE FCST FROM TODAY
INTO SAT. THE 00Z GFS IS VRY CONSISTENT FROM ITS PREV FEW CYCLES
AND ALSO HAD GOOD SUPPORT FROM THE 00Z NON-GFS GUIDANCE. OVERALL
THIS WILL RESULT IN LITTLE CHANGE FROM THE PREV OPC FCST FOR THE
EARLY AM PACKAGE.

LONG TERM...A WARM FRONT IS STILL FCST TO PASS NE OVR PZ5 WTRS SAT
AFTN INTO SAT NITE FOLLOWED BY A WEAK COLD FRONT. WE WILL CONT TO
FCST MARGINAL GALES NEAR AND JUST AHEAD OF THE WARM FRONT OVR PZ5
WTRS SAT...WITH THE GALES LIFTING N OF THE WTRS SAT NITE. CONFDC
LVLS IN THESE GALES IS NEAR TO BELOW AVERAGE. THE WEAK COLD FRONT
WILL THEN LKLY STALL EITHER OVR THE NW PORTION OF THE PZ5 WTRS OR
JUST NW OF THE WTRS SUN INTO SUN NITE...WITH HIGH PRES DOMINATING
SE PZ5 AND NW PZ6 WTRS...AND A COASTAL TROF PERSISTING ALONG THE
SRN AND CENTRAL CAL COASTLINE. FOR SAT AFTN INTO SUN NITE WE WILL
ONCE AGAIN RELY ON THE 00Z GFS 30M WINDS FOR THE EARLY AM PACKAGE
AS THE 00Z GFS REMAINS QUITE CONSISTENT OVR THE OFF WTRS SAT INTO
SUN NITE...AND IS SIMILAR TO THE 00Z ECMWF... 00Z CANADIAN...AND
00Z UKMET MDL GUIDANCE. DURING THE DAY MON AND MON NITE THE 00Z
MDLS DIVERGE MAINLY REGARDING LOW PRES TRACKING NE ALONG THE
STALLED FRONT OVR NW PZ5 WTRS. AS A RESULT...TO MAINTAIN
CONTINUITY IN THE FCST WE WILL CONT TO USE THE PREV OFFICIAL
GRIDS FOR THE OFF WTRS FCST FOR MON AND MON NITE.

SEAS...BASED ON THE LATEST OBS AND ALTIMETER DATA OVR THE FAR ERN
N PACIFIC OCEAN EARLY TODAY...THE 00Z ENP WW3 APPEARS TO BE
RUNNING A COUPLE FT TOO HIGH ESPEC OVR PZ5 WTRS BASED ON THE
LATEST OBS...WITH THE 00Z ECMWF WAM INTIALIZING JUST A TAD
BETTER. FOR THE EARLY AM PACKAGE WE WILL USE A 50-50 BLEND OF THE
ENP WW3 AND ECWMF WAM IN AN ATTEMPT TO LOWER THE 00Z ENP WW3 MDL
OUTPUT SLIGHTLY FOR TODAY INTO FRI. LONG PERIOD...20-22 SEC...
W-NW SWELLS OVR PZ5 AND NRN CALIF OFF WTRS EARLY TODAY WILL
SPREAD SE INTO CENTRAL AND SRN CALIF WTRS THROUGHOUT TODAY INTO
THIS EVE WITH THESE LONGER SWELLS DIMINISHING FROM NW TO SE OVR
THE WTRS FRI INTO SAT. FOR FRI NITE INTO SUN NITE...WE WILL CONT
TO USE A 50-50 BLEND OF THESE TWO WV MDLS WITH THEIR OUTPUT BCMG
QUITE SIMILAR FOR THIS TIME FRAME. FOR MON AND MON NITE...WE WILL
USE THE PREV GRIDS AND FCST WHICH WILL MAINTAIN FCST CONTINUITY
FOR THE EARLY AM PACKAGE.

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


.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
.PZZ800...INNER WATERS FROM CAPE FLATTERY TO CAPE SHOALWATER...
     GALE TODAY.
     GALE POSSIBLE SAT.
.PZZ900...OUTER WATERS FROM CAPE FLATTERY TO CAPE SHOALWATER...
     GALE TODAY INTO TONIGHT.
     GALE POSSIBLE SAT.
.PZZ805...INNER WATERS FROM CAPE SHOALWATER TO CAPE LOOKOUT...
     GALE TODAY.
     GALE POSSIBLE SAT.
.PZZ905...OUTER WATERS FROM CAPE SHOALWATER TO CAPE LOOKOUT...
     GALE TODAY INTO TONIGHT.
     GALE POSSIBLE SAT.
.PZZ910...OUTER WATERS FROM CAPE LOOKOUT TO FLORENCE OR...
     GALE TODAY.
     GALE POSSIBLE SAT.
.PZZ915...OUTER WATERS FROM FLORENCE OR TO POINT ST. GEORGE...
     GALE TODAY.

.PZ6 CALIFORNIA WATERS...
     NONE.

$$

.FORECASTER MUSONDA/MILLS. OCEAN PREDICTION CENTER.


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