Marine Interpretation Message
Issued by NWS

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AGPN40 KWNM 231425
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
725 AM PDT WED JUL 23 2014

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

A WEAK LOW PRES CENTER OVER THE NE PZ5 WTRS HAS MAX ASCD WINDS
UP TO 20 OR 25 KT WHICH IS IN LINE WITH THE LATEST FCST MDLS. MAX
ASCD SEAS ARE ONLY IN THE 5-7 FT RANGE WHICH ARE BEING HANDLED
FINE BY THE 06Z WAVEWATCH III AND 00Z ECMWF WAM MDLS AT THE
MOMENT.

OVER THE SHORT TERM...THE LATEST MDLS CONT TO FCST THIS LOW TO
REMAIN WEAK AS ITS DRIFTS EWD TODAY. BUT AS STRONG HIGH PRES
BUILDS IN FM THE W THE 06Z GFS/NAM REMAIN CONSISTENT WITH THEIR
PREV RESPECTIVE RUNS IN FCSTG THE GRADIENT OVER ITS W AND SW
QUADRANTS TO STRENGTHEN UP TO 25 OR 30 KT. BUT THEN TONITE AS ITS
ASCD CLOSED UPR LOW MOVES INLAND ALL OF THE MDLS FCST THE ASCD SFC
LOW TO MOV INLAND AND DISSIPATE ALWG THE GRADIENT IN ITS WAKE TO
WEAKEN ACRS THE PZ5 WTRS THRU TONITE INTO THU NITE.

FURTHER S THO...AS THE MDLS FCST THE HIGH PRES RIDGE TO BUILD
ACRS THE PZ5 WTRS...IT WL COMBINE WITH THE INLAND CALIFORNIA SFC
TROF TO CAUSE A STRENGTHENING NNWLY GRADIENT TO DVLP ACRS MUCH OF
THE PZ6 WTRS THU/THU NITE. WITH THE 06Z NAM/GFS REMAINING
CONSISTENT IN FCSTG THIS GRADIENT TO ATTAIN MARGINAL GALE FORCE BY
LATE THU/THU NITE...DO NOT PLAN ON REPOPULATING OUR SHORT TERM
FCST WIND GRIDS WHICH USED A COMBINATION OF THE 00Z GFS 10M AND
30M WINDS. SO ANTICIPATE MAKING ONLY GNRLY MINOR SHORT TERM CHNGS
IN THE NEXT OFSHR FCST PACKAGE.

IN THE LONG RANGE...BY LATE FRI INTO SAT THE LATEST GLOBAL MDLS
ARE IN RSNBLY GOOD AGRMT THAT THE HIGH PRES RIDGE ACRS THE PZ5
WTRS WL GRADLY WEAKEN. AGAIN WITH THE 06Z GFS RMNG CONSISTENT WL
CONT WITH THE PREVLY USED 00Z GFS 30M BL WINDS AND WL ALLOW THE
MARGINAL GALE WRNG TO END FRI NITE. THEN SAT INTO SUN NITE THE
GLOBAL MDLS ALL FCST THE HIGH PRES RIDGE TO REMAIN IN PLACE ACRS
THE NRN PZ5 WTRS WHL MAINTAINING A MOD STRONG (UP TO 25 OR 30 KT)
NLY GRADIENT TO ITS SE ACRS THE SE PZ5 AND NRN PZ6 WTRS. THE PREV
OFSHR FCST PACKAGE CONTD WITH THE 00Z GFS 30M BL WINDS THRU SUN
NITE AND PER THE 06Z GFS DO NOT SEE ANY REASON TO REPOPULATE FOR
NOW. SO PLAN ON MAKING MINIMAL LONG RANGE CHNGS TO THE PREV OFSHR
FCSTS.

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

00Z GLOBAL MODELS IN GOOD AGRMT THRU FCST PERIOD. POPULATED WIND
GRIDS WITH 10M WINDS FROM THE 00Z GFS THRU 00Z THU...THEN 30M
WINDS WITH SOME MINOR TWEAKS THEREAFTER. 00Z GFS HAS GOOD SUPPORT
FROM BOTH THE ECMWF AND THE UKMET.

LOW PRES NR 46N126W IS EXPECTED TO REMAIN NEARLY STATIONARY OVER
THE NEXT 12 TO 24 HOURS...WHILE SLOWLY STRENGTHENING. MAJORITY OF
THE GLOBAL MODELS STILL SHOWING AREA OF 20 TO 30 KT WINDS DVLPG IN
THE W AND SW QUAD OF THE LOW OVER THE PZ5 WATERS LATER TODAY AND
INTO TONIGHT. LOW EXPECTED TO MOVE INLAND LATER TONIGHT INTO THU
WITH CONDITIONS DIMINISHING.

HIGH PRES RIDGE THEN BUILDS OVER THE NW WATERS THU AND THU
NIGHT...WHILE LOW PRES TROF EXTENDS NWRD ACROSS THE NRN CALIF
COAST. BORDERLINE GALE CONDITIONS POSSIBLE FOR THE PZZ820 WATERS
THU NIGHT AND AGAIN LATE FRI INTO FRI NIGHT AS THIS PATTERN
PERSISTS. STRONGEST CONDITONS ARE EXPECTED TO BE IN THE ADJACENT
CSTL WATERS...WITH BORDERLINE GALE CONDITIONS ONLY EXPECTED TO BE
OVER THE FAR ERN PORTIONS OF THE OFFSHR ZONE. PATTERN WEAKENS
SLIGHTLY SAT AND SAT NIGHT...WITH EVEN GFS 30M WINDS SHOWING
SUBGALE CONDTIONS DURING THIS TIME PERIOD. WILL TAKE OUT GALES FOR
LATE SAT AND SAT NIGHT IN THE NEXT PACKAGE...AS ANY GALES SHUD BE
CONFINED TO THE CSTL ZONES.

PATTERN CONTINUES TO SLOWLY WEAKEN SUN AND SUN NIGHT...AS TROF
EXTENDS FURTHER NWRD ALONG THE OR COAST.

.SEAS...ENP VERSION OF WWIII WITHIN A FT OR TWO OF CURRENT OBS.
POPULATED WAVE GRIDS FROM 00Z ENP THRU THE FCST PERIOD. DID INCR
SEAS BY 10 PERCENT IN THE GALE AREA THU NIGHT...AND 5 PERCENT FRI
NIGHT.

.EXTRATROPICAL STORM SURGE GUIDANCE...N/A

.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
     NONE.

.PZ6 CALIFORNIA WATERS...
.PZZ820...INNER WATERS FROM POINT ST. GEORGE TO POINT ARENA...
     GALE THU NIGHT.
     GALE POSSIBLE FRI INTO FRI NIGHT.

$$

.FORECASTER VUKITS/ACHORN. OCEAN PREDICTION CENTER.



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