Marine Interpretation Message
Issued by NWS

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AGPN40 KWNM 252044
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
144 PM PDT SAT APR 25 2015

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


AFTER SEVERAL DAYS OF MODEL CHAOS 12Z SUITE OF GLOBAL GUID IS
FINALLY COMING INTO BETTER AGRMT ACRS THE ERN PAC. THE AFTN GRIDS
WILL BE POPULATED USING THE 12Z GFS 30M WINDS INTO 12Z MON...THEN
THE 12Z ECMWF THEREAFTER.

XPCT QUICK ROUND OF GALES TO SPREAD INTO THE W-RN WASH WTRS JUST
BFR 06Z TNGT AHD OF A STG APRCHG FRONTAL BOUNDARY AS PARENT LOPRES
STRENGTHENS INTO THE W-RN GLFAK. FCST WINDS WL CONT TO BE CAPPED
AT 40 KT...BUT STILL XPCT STORM FORCE WINDS N OF OUR WATERS IN THE
PINCHING BW THE BNDRY AND VANCOUVER ISL.

FARTHER S A CDFNT IS ON THE DOORSTEP OF THE SRN CAL ZNS. THE
FRONT WL CONT ITS QUICK S-WARD PROGRESSION THRU THE AFTN AND CLR S
OF...OR DSIPT ACRS...THE SRN WTRS THIS EVE OR EARLY TNGT. BHND THE
FROPA HIGH PRES WL NOSE IN FROM THE W AS A SFC LOW DVLPS INLAND
ACRS THE GREAT BASIN. RESULTANT PRES GRAD WILL STG ENUF TO SUPPORT
MARG GALES...AND STILL FEEL THESE CONDS THAT MEET WARNING CRITERIA
WILL LIKELY BE IN GUSTS WITHIN THE CSTL ZNS NEAR THE CHANNEL
ISLANDS. WITH THAT BEING SAID CANNOT RULE OUT THESE HIER WINDS
MAKING IT INTO THE INNER ZNS...SO WILL LEAVE GALE HEADLINES AS IS
WITH LOW CONFDC. AND BASED ON 12Z GUID WL XTND AREAL EXTENT OF
GLW TO INCD PZZ835 WHICH WILL ALSO BETTER MATCH CSTL FCSTS. XPCT
MINIMAL GALES TO ABATE BLO WARNING CRITERIA JUST BFR 12Z MON.

12Z MON AND BYND MODEL GUID HAS FINALLY CONVERGED ON SMLR SOLNS
AS AN UPR S/W NR HAWAII LIFTS QUICKLY NE-WARD ACRS THE NEPAC WHILE
PHASING WITH STGR S/W TROF ROUNDING BASE OF BROAD UPR LOW ACRS THE
GLFAK. AT THE SFC THE LOW IS XPCTD TO PASS JUST NW OF THE WASH
WTRS INTO WRN BC WHILE QUICKLY PULLING A CDFNT ACRS THE AREA TUE.
FOR THE PAST SEVERAL CYCLES THE GFS HAS BEEN CHASING THIS
PREFERRED ECMWF/UKMET SOLN. GALES AHD OF QUICKLY MVG CDFNT NOT
XPCTD TO EXCEED 30 KT...WHICH HAS BEEN THE ONGOING FCST...AND
SHUD BE CONFINED TO AREAS N OF THE PZ5 WTRS AND INVOF AND N OF
VANCOUVER ISL.

AFTER FROPA TUE A MORE CLASSIC SYNOPTIC PATTERN SETS UP ACRS OF
THE OFSHR WTRS FOR THE RMNDR OF FCST AS A THERMAL TROF DVLPS AND
XPNDS ALONG THE CAL COAST...AND A STG HIGH PRES BUILDS ACRS THE
EPAC. ALL GUID IN GUD AGRM WITH THIS UPCOMING PATTRN AND EACH
SUGGEST PRES GRAD THAT MAY BE STG ENUF TO SUPPORT MINIMAL GALES.
WL CONT TO CARRY NO WARNING HEADLINES DURING THE LATER TIME
FRAME...HOWEVER WILL CAP WINDS TO 30 KT WITH INCRSG CONFDC IN
PATTERN (AS OPPOSED TO 25 KT MAX IN PREV FCSTS).

SEAS...WILL USE THE 12Z ECMWF WAM THRUT...HWVR WILL MAX SIG WVHTS
TO 14 FT TWDS END OF THE FCST WHERE ECMWF HINTS AS POSSIBLE GALES.

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

.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
.PZZ800...INNER WATERS FROM CAPE FLATTERY TO CAPE SHOALWATER...
     GALE SUN.
.PZZ900...OUTER WATERS FROM CAPE FLATTERY TO CAPE SHOALWATER...
     GALE TONIGHT INTO SUN.

.PZ6 CALIFORNIA WATERS...
.PZZ835...INNER WATERS FROM POINT PIEDRAS BLANCAS TO SANTA CRUZ ISLAND, CA...
     GALE SUN NIGHT.
.PZZ840...INNER WATERS FROM SANTA CRUZ ISLAND, CA TO SAN CLEMENTE ISLAND, CA...
     GALE TONIGHT INTO SUN NIGHT.

$$

.FORECASTER COLLINS. OCEAN PREDICTION CENTER.



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