Marine Interpretation Message
Issued by NWS

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AGPN40 KWNM 010334
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
834 PM PDT FRI JUL 31 2015

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

THE IR SAT IMG INDC MOSTLY CLR SKIES WTH JUST A FEW THIN CLDS NR
NRN CA WTRS AND THERE IS NO INDC OF LGHTNG EVEN WITHIN THE VCNTY.
THE RADAR SHOWS NO INDC OF TSTMS CELLS ACRS THE REGION. AT
01/0000Z HGH PRES TO THE W WITH ONE CNTR 1026 MB NR 45N135W HAS A
RIDGE ACRS THE NRN WTRS. LOW PRES 1015 MB W OF RGE SRN WTRS HAS A
TROF XNTNG NE INTO THE CNTRL WTRS WHICH IS ASSCTD WITH THE THIN
CLDS. THE SRN PARTS IS COVRD BY ANOTHER HIGH PRES RIDGE WHICH IS
PART OF THE HGH MENTIONED ABOVE. A SERIES OF LOWS ARE ALONG THE
TROF AXIS THAT XTND JUST INLAND FROM SRN CA INTO OREG AND WASH
STATES. THE PRES GRDNT IS FAIRLY SLCK AND THE OBSVD MAX WINDS ARE
20 KT. THE LAST R-SCAT AT 1926Z HAD 20 KT WINDS OVR THE NRN WTRS
AND BTWN 5 AND 15 KT ELSEWHERE. THE SEAS ARE EQUALLY SMALL WITH
ONLY 9 FT PEAK OVR THE CNTRL WTRS WHILE THEY RANGE BTWN 3 AND 6 FT
ELSEWHERE. THE NWW3 MULTI GRID WV MDL FIST VERY WELL WITH THE
OBSVD SEAS PATTERN AND IS QUITE CLOSE TO THE ECMWFWAVE ESPCLY IN
THE SHORT TERM.

THE ONLY SIG ENRGY NR THE WTRS IS THAT ASSOCTD WITH THE LOW PRES
JUST W OF THE SRN WTRS. UN UPPRLVL RIDGE ACRS THE REGION HAS
BLOCKED ANY EASTWARD SHIFT OF THE ENRGY AND THAT WILL BE THE CASE
IN THE SHORT TERM. IN THE XTNDD PRD SIG ENERGY WILL BE INDCD IN
THE GULF OF AK AND APPROACH THE NRN WTRS BUT WILL ONLY PASS N AND
THAT WILL HAVE LESS IMPACT ON THE PRES GRDNT OVR THE RN WTRS.
MEANWHILE THE ENERGY TO THE W OF THE SRN WTRS WILL ALSO INCRS BUT
WILL REMAIN WITHIN THE SAME VCNTY AND JUST STRENGTHEN THE SFC LOW
PRES IN THE SAME AREA. AS SUCH THE FCST REGION WILL REMAIN UNDER
THE INFLUENCE OF HGH PRES RIDGE AND THE INLAND TROF WILL REMAIN
WEAK THRU THE PRD.

THE GLBL MDLS HV INITALIZED WELL AND THEY HAVE NO DIFFS ESPCLY IN
THE SHORT TERM. EVEN IN THE XTNDD PRD THAY JUST HV MNR DIFFS ON
THE STRENGTH OF THE LOW PRES TROF ACRS THE CNTRL WTRS THAT WILL BE
ASCCTD WITH THE ERNGY TO THE W OF THE REGION. OTHERWISE THE MDLS
ARE IN A FAIRLY GUD AGREMNT AND SO WILL CONTNE TO USE THE GFS AS
MAIN GDNC. IN THE SHORT TERM THE HGHPRES WILL PERSIST TO THE W OF
THE REGION BUT WILL WEAKEN SLIGHTLY WHILE THE INLAND TROF WILL
ALSO PERSIST BUT WEAKEN. WINDS WILL REMAIN BELO GALE FORCE THRU
THE FCST PRD AND SEAS WILL ALSO REMAIN BELOW 12 FT.

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

HIGH PRES CURRENTLY CENTERED W OF THE PZ5 WATERS CONTINUES TO
COMBINE WITH WEAK LOW PRES NEAR THE COAST OF NRN CALIFORNIA TO
PRODUCE N TO NE WINDS ACROSS THE SRN PZ5 AND NRN PZ6 WATERS WITH
WINDS AS HIGH AS 20 OR 25 KT. BY TONIGHT NRLY WINDS WILL INCREASE
TO 25 OR 30 KT ACROSS ERN PORTIONS OF THE PZ5 WATERS AND THEN
CONTINUE INTO SAT NIGHT. THESE WINDS WILL THEN DIMINISH BY SUN.
FARTHER S...NW WINDS WILL INCREASE TO 25 KT OR SO OFF THE COAST OF
SRN CALIFORNIA BY SUN NIGHT AS INLAND LOW PRES OVER THE SW U.S.
STRENGTHENS. THESE WINDS WILL THEN CONTINUE INTO TUE NIGHT. THE
STRONGEST WINDS WILL THEN SHIFT N TO THE AREA W OF CAPE MENDOCINO
BY WED NIGHT. MEANWHILE...WEAK LOW PRES W OF THE PZ6 WATERS WILL
REMAIN NEARLY STATIONARY AND THEN DISSIPATE BY MON NIGHT. CURRENT
FORECAST LOOKS REASONABLE AND WILL CONTINUE TO CARRY NO WARNINGS
ACROSS THE OFFSHORE WATERS DURING THE FORECAST PERIOD.

THE ENP VERSION OF THE NWW3 LOOKS REASONABLE WITH THE SEAS AND
WILL CONTINUE TO FOLLOW IT FAIRLY CLOSELY DURING THE FORECAST
PERIOD.

EXTRATROPICAL STORM SURGE GUIDANCE...N/A.


.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
     NONE.

.PZ6 CALIFORNIA WATERS...
     NONE.

$$

.FORECASTER MUSONDA/NOLT. OCEAN PREDICTION CENTER.


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