Marine Interpretation Message
Issued by NWS

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AGPN40 KWNM 040249
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
649 PM PST TUE MAR 3 2015

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

THE IR SAT IMG INDCT ALMOST CLR SKIES WITH NO LIGHTNG OVR THE
REGION. THE RADAR ALSO HAS NO INDC OF TSTMS CELLS OVR THE WTRS
AND EVEN WITHIN ITS VCNTY. AT 0000Z HGH PRES 1032 MB CNTRD 40N140W
HAS ITS RIDGE OVR THE NRN WTRS WITH ITS SE RIDGE AXIS PASSING W OF
THE SRN WTRS. INLAND TROF STRETCHES NW FROM AZ THRU NV THEN INTO
NRN CA AND THE COAST OF OREG. LOW PRES 1012 MB SE OF THE ALEUTIAN
ISLANDS HAS A FRNT PASSING W OF THE HGH PRES NOTED ABOVE. UPSTREAM
IS ANOTHER HGH PRES 1038 MB OVR CNTRL PAC. THE PRES GRDNT IS
FAIRLY SLACK OVR THE REGION AND THE OBSVD WINDS RANGE BTWN 10 AND
20 KT. THE LAST R-SCAT PASS AT 1932Z HAD NO WINDS ABOVE 20 KT ACRS
THE REGION. THE SEAS ARE HGHST OVR THE CNTRL AND SRN WTRS PEAKING
AT 10 FT WHILE THEY RANGE BTWN 4 AND 6 OVR THE NRN WTRS. NO LTST
JASON PASS SINCE 1255Z WHICH ACTUALLY MISSED THE ENTIRE REGION.
NWW3 FITS WELL WITH THE OBSVD SEAS PATTERN AND HAS BEEN QUITE
CONSISTTNT WITH THE FCST SEAS. NWW3 IS ALSO CLOSE TO THE
ECMWFWAVE AND SO WILL STAY CLOSE TO IT.

AN UPPRLVEL RIDGE JUST W OF THE REGION HAS KEPT ALL THE ENRGY E
OF THE WTRS XCPT FOR SOME ENRGY FROM A BACK HANGNG INLAND UPPRLVL
TROF THAT STRTCHES INTO THE FAR SRN WTRS INLINE WITH 20 KT WINDS
AND HGHR SEAS NOTED ABOVE. UPPERLVL RIDGE WILL SHIFT E AND BE OVR
THE REGION THRU THE FCST PRD. AS SUCH A MDL CHOICE SHUD BE ONE
THAT WILL KEEP SHIFTING WINDS MAINLY FROM N TO SW UP TO 20 KT.

THE GLBL MDLS HV INITILAIZED WELL AND THEY ARE IN DECENT AGRMNT
WITH JUST MNR DIFFS IN THE WIND SPEED WHEN LOW PRES PASSES TO THE
NW. OTHERWISE WILL CONTNE WITH GFS. IN THE SHORT TERM THE HGH
PRES WILL REMAIN ANCHORED TO THE W AND THAT WILL PREVENT FRNTL
SYSMS FROM REACHING THE WTRS. AS HGH PRES SHIFTS E... A FRNTL
SYSTEM WILL ALSO MOVE CLSR TO THE WTRS BUT WILL STILL BE BLOCKED
AND STALL THUS WILL ONLY ALLOW THE LOW PRES TO GLIDE NE AND DISPT
NW OF THE REGION. ANOTHER LOW PRES WILL DVLP ON THE QSTNRY FRNT
BUT THAT WILL BE AT THE END OF THE FCST PRD AND WILL NOT BE IN THE
WTRS. AS SUCH THE PRES GRDNT WILL REMAIN RELAXED THRU THE FCST PRD
AND WINDS WILL NOT REACH GALE FORCE THRESHOLD.



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

THE 18Z SFC ANALYSIS INDICATED HIGH PRES RIDGE W OF THE OFFSHORE
WATERS ALONG 140W...WITH A WEAK TROUGH ALONG THE CA AND OREGON
COAST...AND WEAK LOW PRES OVER THE FAR SE S CA WATERS. LIGHTNING
DATA STILL INDICATING A FEW STRIKES OVER THE FAR SE ZONE OF S CA
OFFSHORE WATERS IN VCNTY OF LOW. NO NEW ASCAT DATA...HOWEVER
RECENT RAPID SCAT PASS FROM LATE TUE MORNING INDICATED SOME 25 KT
WINDS OVER THE N CA WATERS...OTHERWISE WINDS WERE MOSTLY IN THE 15
TO 20 KT RANGE.

THE 12Z MODELS CONTINUE TO BE IN VERY GOOD AGREEMENT THROUGH THE
FCST PERIOD. THE MODELS DO DIFFER WITH THE INTENSITY OF LOW FCST
TO PASS WELL W OF THE AREA WED NIGHT INTO FRI...HOWEVER THESE
DIFFERENCES WILL HAVE MINIMAL IMPACT ON THE OFFSHORE/COASTAL
WATERS. THE GFS/UKMET SEEM TO BE IN DECENT AGREEMENT WITH THE
TRACK AND INTENSITY OF LOW...WHILE THE ECMWF/CMC ARE WEAKER.
MEANWHILE...WEAK HIGH PRES RIDGE WILL PERSIST OVER THE OFFSHORE
WATERS WITH WEAK TROUGH ALONG THE COAST. THIS WILL RESULT IN A
LIGHT WIND REGIME WITH WINDS REMAINING WELL BELOW WARNING
THRESHOLD THROUGH THE WEEKEND. WILL POPULATE GRIDS USING THE 10M
GFS WINDS THROUGHOUT.

.SEAS...THE 18Z SEA STATE ANALYSIS INDICATED THAT OBSERVED WERE
WITHIN A FT OF THE MWW3/ECMWF WAM FCST VALUES. WILL POPULATE GRIDS
USING THE MWW3 THROUGH THE PERIOD.

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


.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
     NONE.

.PZ6 CALIFORNIA WATERS...
     NONE.

$$

.FORECASTER MUSONDA/KOSIER. OCEAN PREDICTION CENTER.


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