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
AGPN40 KWNM 290803
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
103 AM PDT FRI APR 29 2016

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

OVER THE SHORT TERM...AN EARLIER 0441Z HI RESOLUTION ASCAT-A PASS
SHOWED MAX WINDS IN THE 25-30 KT RANGE IN THE NNWLY GRADIENT OFF
THE NRN AND CNTRL CALIFORNIA COAST. THE NEW 00Z MDLS ARE IN RSNBLY
GOOD AGRMT THAT THE WEAK COLD FRONT NOW PUSHING SE ACRS THE PZ5
WTRS WL CONT SE INTO THE NRN PZ6 WTRS BY LATE TODAY MAINTAINING
THE CURRENT GRADIENT...THEN DSIPT ACRS THE CNTRL PZ6 WTRS TONITE
WHILE A STRONG HIGH PRES RIDGE BLDS TWDS 130W CAUSING THE GRADIENT
TO BEGIN STRENTHENING WITH GALE FORCE ASCD BL WINDS DVLPG. THEN AS
THE MDLS FCST TO RIDGE TO REMAIN STRONG SAT INTO SAT NITE...THEY
FCST A LOW PRES TROF TO SHARPEN NR THE CALIFORNIA COAST WHICH WL
STRENGTHEN THE NNWLY GRADIENT FURTHER WITH THE AREA OF GALE FORCE
ASCD BL WINDS EXPANDING NWD. OVERALL WULD FAVOR THE SLIGHTLY
STRONGER 00Z NAM/GFS/GEM SOLUTIONS FOR THIS GRADIENT (THO THE
USUALLY CONSERVATIVE 00Z NAVGEM/UKMET/ECMWF ALSO FCST GALE FORCE
ASCD BL WINDS). THERFORE PLAN ON POPULATING OUR SHORT TERM FCST
WIND GRIDS WITH A 50/50 BLEND OF THE REPRESENTATIVE 00Z GFS 30M
AND 10M BL WINDS FOR TODAY THRU SAT NITE. SO AS A RESULT DO NOT
ANTICIPATE MAKING ANY SIG TIMING AND/OR AREAL COVERAGE CHNGS TO
THE PREVLY FCSTD GALE WRNGS ASCD WITH THE NNWLY GRADIENT.

IN THE LONG RANGE...AS ALL OF THE 00Z MDLS FCST THE HIGH PRES
RIDGE TO WEAKEN LATE SAT NITE/SUN...THE ASCD NNWLY GRADIENT WL
WKN SIGLY WITH ITS ASCD WINDS BCMG SUBGALE THRUT LATE SAT NITE. WL
CONT TO POPULATE WITH A 50/50 BLEND OF THE 00Z GFS 30M AND 10M BL
WINDS FOR THIS WKNG TREND. THEN SUN NITE INTO MON...TO SLIGHTLY
VARYING DEGREES THE MDLS FCST THE LOW PRES TROF TO EXPAND NWD UP
THE PAC NW COAST WITH A WEAK ASCD LOW TRACKING N ALONG THE TROF
JUST OFF THE OR/WA COASTS. AS A COMPROMISE...WL TRANSITION TO A
50/50 BLEND OF THE 00Z GFS 10M AND 00Z ECMWF BL WINDS SUN
NITE...FLWD BY ALL 00Z ECMWF BL WINDS ON MON. THEN MON NITE INTO
TUE NITE THE 00Z GLOBAL MDLS ALL FCST A VERY WEAK COLD FRONT TO
DRIFT SLOWLY E INTO THE OFSHR WTRS...FLWD BY A HIGH PRES RIDGE
BLDG INVOF 135W CAUSING A MOD STRONG (GNRLY UP TO 20-25 KT)
POSTFRONTAL NNWLY GRADIENT TO DVLP ACRS THE NRN WTRS. OVERALL WULD
FAVOR A BLENDED 00Z GFS/UKMET/ECMWF SOLUTION FOR THIS MOD
POSTFRONTAL GRADIENT VS THE STRONGER 00Z GEM SOLUTION. THEREFORE
WL CONT TO POPULATE WITH THE REPRESENTATIVE 00Z ECMWF BL WINDS MON
NITE THRU TUE NITE...BOOSTED UP 10 PERCENT ON AVERAGE MAINLY IN
DEFERENCE TO THE SLIGHTLY STRONGER 00Z UKMET SOLUTION.

.SEAS...THE SLIGHTLY HIGHER 00Z ECMWF WAM HAS INITIALIZED BETTER
THAN THE 00Z WAVEWATCH III. THEREFORE WL POPULATE OUR FCST WAVE
GRIDS WITH THE 00Z ECMWF WAM FOR TODAY. THEN AS THE DIFFERENCES
BTWN THE TWO MDLS BCM MINIMAL (GNRLY IN THE 1-2 FT RANGE)...WL
TRANSITION TO POPULATING WITH A 50/50 BLEND OF THE TWO MDLS FOR
TONITE THRU MON. THEN SINCE THE 00Z ECMWF SOLUTION WL BCM
FAVORED...WL USE ALL 00Z ECMWF WAM FCST SEAS FOR MON NITE THRU TUE
NITE.

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

.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
.PZZ815...INNER WATERS FROM FLORENCE OR TO POINT ST. GEORGE...
     GALE SAT NIGHT.

.PZ6 CALIFORNIA WATERS...
.PZZ820...INNER WATERS FROM POINT ST. GEORGE TO POINT ARENA...
     GALE TONIGHT INTO SAT NIGHT.
.PZZ825...INNER WATERS FROM POINT ARENA TO PIGEON POINT...
     GALE TONIGHT INTO SAT NIGHT.
.PZZ925...OUTER WATERS FROM POINT ARENA TO PIGEON POINT...
     GALE SAT.
.PZZ830...INNER WATERS FROM PIGEON POINT TO POINT PIEDRAS BLANCAS...
     GALE TONIGHT INTO SAT.
.PZZ930...OUTER WATERS FROM PIGEON POINT TO POINT PIEDRAS BLANCAS...
     GALE SAT.

$$

.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.