Marine Interpretation Message
Issued by NWS

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000
AGPN40 KWNM 121443
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
643 AM PST FRI FEB 12 2016

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

LATEST OBS SHOW WINDS 20 KT OR LESS OVER THE FORECAST AREA. A
COLD FRONT DRAPES THROUGH THE NRN AND CENTRAL PZ06 WATERS.

LOOKS LIKE GALES IN PLACE FOR NRN PZ05 WTRS FOR SAT ARE WELL
PLACED. DO NOT SEE ANY MAJOR SHIFTS IN 06Z GUIDANCE FROM PREVIOUS
FORECAST SO WILL NOT MAKE ANY BIG CHANGES OTHER THAN TO REFRESH
GRIDS.

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

THERE WILL BE A THREAT FOR GALES OVR MAINLY PZ5 OFF WTRS SAT WITH
CONFDC LVLS NEAR AVERAGE. OTW...NO HEADLINES ARE FCST OVR THE OFF
WTRS FOR THE NEXT 3-5 DAYS. THERE IS A SLIGHT CHANCE FOR GALES
OVR THE INNER OFF WTRS OF CENTRAL AND SRN CALIF LTR SAT INTO SUN
AS THE PRES GRAD BETWEEN HIGH PRES W OF THE WTRS...AND A COASTAL
LOW PRES TROF STRENGTHENS. CHANCES ARE NOT HIGH ENOUGH TO ADD
THEM TO THE FCST AT THIS TIME...AND WE WILL KEEP MAX WINDS AT 30
KT FOR THE EARLY AM FCST PACKAGE.

SHORT TERM...HIGH PRES IS WEAKENING OVR CENTRAL CAL OFF WTRS AS A
COLD FRONT MOVES E OVR PZ5 AND NRN CALIF WTRS EARLY THIS MORNING.
OBS AND ASCAT DATA INDICATE THAT GALES ASSOC WITH THE FRONT ARE
OCCURRING N OF THE OFF WTRS CLOSER TO THE MAIN LOW PRES AREA
ASSOC WITH THE FRONT W AND NW OF VANCOUVER ISLAND. THE FRONT WILL
CONT TO PUSH E AND SE TODAY AND WEAKEN. HIGH PRES WILL RE-BUILD
OVR NRN CALIF WTRS TONITE AS A LOW PRES TROF FORMS ALONG THE
CALIF COAST. THE HIGH WILL PERSIST SAT AS THE TROF STRENGTHENS. A
WARM FRONT WILL LIFT NE OVR PZ5 WTRS SAT WITH A DECENT CHANCE FOR
GALES AS NOTED ABOVE. THE WARM FRONT WILL THEN MOVE INLAND SAT
NITE AS LOW PRES DEVELOPS WELL OF THE W OF THE PZ5 WTRS. A WEAK
WARM FRONT WILL LIFT NE OVR PZ5 WTRS SUN AS THE HIGH PREVAILS OVR
NRN CALIF WTRS AND THE LOW PRES TROF NEAR THE CALIF COAST BEGINS
TO SLWLY WEAKEN BY SUN EVE. OVERALL...THE 00Z MDLS ARE IN VRY
GOOD AGREEMENT OVR THE OFF WTRS THRU SUN. WE WILL USE THE 00Z GFS
AS A RESULT FOR THE EARLY AM PACKAGE...PREFERRING TO USE THE 10M
WINDS FOR MOST OF THE FCST THRU SUN...EXCEPT THE SOMEWHAT HIGHER
30M WINDS NR THE WARM FRONT CROSSING PZ5 WTRS SAT. BOTH THE 00Z
NAM AND 00Z ECMWF INDICATE THAT THE PRES GRAD MAY BE A LITTLE
STRONGER THAN WHAT IS INDICATED BY THE 00Z GFS OVR PZ5 WTRS ON
SAT. THEREFORE BY USING THE STRONGER 30M GFS WINDS THIS WILL
HOPEFULLY BETTER CAPTURE THE WINDS EXPECTED OVR PZ5 WTRS AT THAT
TIME. THIS WILL ALSO MAINTAIN FCST CONTINUITY FOR THE EARLY AM
PACKAGE.

LONG TERM...THE 00Z MDLS REMAIN IN GOOD AGREEMENT OVR THE WTRS SUN
NITE. MDL GUID SUGGESTS THAT A WEAK COLD FRONT WILL STALL AS IT
MOVES INTO NW PZ5 WTRS. HIGH PRES WILL CONT DOMINATING NRN CALIF
OFF WTRS ALONG WITH THE PERSISTENT CALIF COASTAL LOW PRES TROF SUN
NITE. WE WILL STAY CLOSE TO THE 00Z GFS 10M WINDS AS A RESULT FOR
SUN NITE. THE 00Z MDLS BEGIN TO SHOW DIFFERENCES MON THRU TUE NITE
OVR THE ERN PAC. THE HIGH PRES AREA WILL LKLY PERSIST OVR NRN
CALIF WTRS AS WILL THE WEAKENING CALIF COASTAL TROF ON MON...WITH
MOST MDLS LIFTING THE STALLED FRONT N AS A WARM FRONT OVR NRN PZ5
WTRS. MDLS DIFFER SOMEWHAT ON THE LOCATION OF LOW PRES TO THE W
AND NW OF WASH WTRS ON MON. FOR MON NITE AND TUE...BOTH THE HIGH
AND COASTAL LOW PRES TROF WILL LKLY CONT TO WEAKEN WITH LOW PRES
DRIFTING E OVR THE GULF OF AK...WELL TO THE W AND NW OF THE PZ5
WTRS. BY TUE NITE...MOST OF THE 00Z GLBL MDLS SUGGEST THAT LOW
PRES WILL ORGANIZE TO THE W OF THE WTRS AND DRIFT E. THE LOCATION
AND INTENSITY OF THE LOW VARY FAIRLY SIGNIFICANTLY PER EACH
SEPARATE MDL SOLUTION. GEFS MEMBERS INDICATE LOW PRES AREAS WDLY
SCTD ANYWHERE FROM NR 35N 135W N INTO THE GULF OF AK TUE NITE. AS
A RESULT...WE WILL USE A 50-50 BLEND OF THE 00Z GFS AND 00Z ECMWF
FOR MON THRU TUE NITE OVR THE OFF WTRS...WITH ANY GALES LKLY
HOLDING TO THE W AND NW OF THE WTRS AT THAT TIME.

.SEAS...THE 00Z ENP WV WATCH III MDL GUID APPEARS TO BE RUNNING
MOSTLY WITHIN A COUPLE FT OF MOST OF THE OBS OVR AND NR THE OFF
WTRS EARLY THIS MORNING. WE WILL MAKE A FEW MINOR TWEAKS TO THE
GRIDS AND FCST INITIALLY TO BETTER REPRESENT THE ACTUAL
CONDITIONS PRIOR TO FCST ISSUANCE...BUT OTW...AS WE WILL REMAIN
CLOSE TO THE 00Z GFS FOR WINDS...WE WILL RELY ON THE 00Z ENP WW3
FOR THE SEA HT FCST FOR TODAY THRU SUN NITE. LONG PERIOD W-NW
SWELLS AROUND 20 SEC OVR THE WTRS EARLY TODAY WILL SLOWLY DECAY
OVR THE NEXT 24 HRS OR SO. FOR MON THRU TUE NITE...WE WILL USE A
50-50 BLEND OF THE WW3 AND ECMWF WAM MDLS FOR SEA HTS AS WE USE A
SIMILAR BLEND FOR FCST WINDS OVR THE OFF WTRS.

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



.WARNINGS...PRELIMINARY.

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

.PZ6 CALIFORNIA WATERS...
     NONE.

$$

.FORECASTER LEE/MILLS. OCEAN PREDICTION CENTER.


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