Marine Interpretation Message
Issued by NWS

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000
AGPN40 KWNM 250809
MIMPAC

MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
109 AM PDT SUN SEP 25 2016

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

SUMMARY...FOR THE MOST PART THE 00Z GLOBAL MODELS REMAIN IN VERY
GOOD AGREEMENT OVER THE EASTERN NORTH PACIFIC OCEAN DURING THE
NEXT 5 DAYS. AN UPPER LEVEL HIGH PRESSURE RIDGE CURRENTLY
CENTERED ALONG 125W OR SO WILL SLOWLY WEAKEN AND SHIFT INLAND
DURING THE NEXT 24-48 HOURS AS AN UPPER LEVEL TROUGH SLIDES EAST
OVER THE GULF OF ALASKA. THE TROUGH WILL WEAKEN AS IT SLIDES EAST
OVER WESTERN CANADA ON MON. A WEAK RIDGE WILL DEVELOP IN THE WAKE
OF THIS TROUGH OVER THE FAR EASTERN NORTH PACIFIC TUE AS UPPER
LEVEL LOW ORGANIZES OVER THE EASTERN AND CENTRAL GULF OF ALASKA.
THIS SYSTEM WILL MOVE EAST AND SOUTHEAST TOWARD THE OFFSHORE
WATERS WED...AND BEGIN TO CROSS THE WATERS THU. AT THE SURFACE WE
STILL EXPECT COLD FRONTS TO IMPACT ESPECIALLY WASHINGTON AND
OREGON WATERS MON AND MON NIGHT...AND AGAIN WED NIGHT INTO THU
NIGHT...AS NOTED IN PREVIOUS OPC FORECASTS.

MODELS AND HEADLINES...AS THE 00Z GLOBAL MODELS REMAIN WELL
CLUSTERED AND QUITE CONSISTENT WE WILL RELY ON THE 00Z GFS 10M
WINDS FOR THE EARLY MORNING FORECAST PACKAGE. THIS WILL RESULT IN
ONLY MINOR CHANGES FROM THE PAST FEW OPC FORECASTS...WITH NO
HEADLINES CURRENTLY EXPECTED OVER THE OFFSHORE WATERS DURING THE
NEXT 3 TO 5 DAYS. GALES ARE CURRENTLY OCCURRING NORTH OF THE
WATERS NEAR VANCOUVER ISLAND PER THE LATEST OBSERVATIONS AND
A-SCAT OVERPASSES. GALES ARE STILL FORECAST TO REMAIN NORTH OF
THE OFFSHORE WATERS DURING THE NEXT 24 TO 48 HOURS AS LOW PRES
AREAS TRACK NORTH AND NORTHEAST AND PASS WEST AND NORTH OF THE
OFFSHORE WATERS. THERE IS A CHANCE FOR GALES OFF THE NORTHERN
CALIFORNIA AND SOUTHERN OREGON COASTS TUE AFTERNOON INTO WED AS
THE PRESSURE GRADIENT TIGHTENS BETWEEN HIGH PRESSURE WEST OF THE
WATERS AND LOWER PRESSURES NEAR THE COAST AND INLAND OVER THE
ROCKIES. AT THIS TIME...IT APPEARS AS IF THE BEST CHANCE FOR
THESE GALES WILL BE OVER THE COASTAL WATERS WITH CHANCES
REMAINING TOO LOW TO ADD TO THE OFFSHORE FORECAST FOR THIS
PACKAGE. OVERALL...THE CONFIDENCE LEVELS IN THE EARLY MORNING
FORECAST ARE ABOVE AVERAGE AS THE 00Z MODELS ARE IN VERY GOOD
AGREEMENT THROUGH THU NIGHT.

.SEAS...THE 00Z ECMWF WAM WAVE MODEL OUTPUT APPEARS TO BE A LITTLE
BETTER THAN THE 00Z WAVE WATCH III MODEL OUTPUT BASED ON THE
LATEST OBSERVATIONS AND ALTIMETER DATA OVER THE EASTERN NORTH
PACIFIC EARLY THIS MORNING. MAXIMUM SEA HEIGHTS NEAR VANCOUVER
ISLAND ARE NEAR 18 FT OR SO...WITH 10 FT SEAS OCCURRING OFF THE
CENTRAL CALIFORNIA COAST PER THE 06Z RP1 SEA STATE ANALYSIS...
WITH THESE MAX HEIGHTS BETTER REFLECTED BY THE 00Z WAM GUIDANCE.
WE WILL THEREFORE REMAIN CLOSER TO THE 00Z WAM WAVE GUIDANCE
THROUGHOUT THE NEXT FORECAST PACKAGE...WITH THE 00Z WAVE WATCH
III MODEL GUIDANCE POTENTIALLY OVER FORECASTING SEA HEIGHTS LATER
TUE INTO WED OFF THE SOUTHERN OREGON AND NORTHERN CALIFORNIA
COASTS. SOME MANUAL EDITS WILL BE MADE SO THAT OPC WAVE HEIGHTS
FORECAST FIT WITH NEARBY COASTAL AND TAFB FORECASTS THROUGH THE
NEXT FORECAST PACKAGE.

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

.WARNINGS...PRELIMINARY.

.PZ5 WASHINGTON/OREGON WATERS...
     NONE.

.PZ6 CALIFORNIA WATERS...
     NONE.

$$

NOTE: ON OCTOBER 06, 2016...THE NWS FTPMAIL SERVICE WILL DISABLE
THE CURRENT EMAIL ADDRESS. THE NEW EMAIL ADDRESS IS LIVE NOW.
PLEASE TRANSITION TO IT AS SOON AS POSSIBLE TO AVOID A SERVICE
DISRUPTION.

NEW EMAIL ADDRESS...NWS.FTPMAIL.OPS@NOAA.GOV
/ALL LOWER CASE LETTERS/

FOR THE SERVICE CHANGE NOTICE...PLEASE GO TO
HTTP://WWW.NWS.NOAA.GOV/OS/NOTIFICATION/SCN16-37FTPMAIL.HTM
/ALL LOWER CASE LETTERS/

.FORECASTER MILLS. OCEAN PREDICTION CENTER.



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