

225 

AGPN40 KWNM 250836

MIMPAC



MARINE WEATHER DISCUSSION FOR N PACIFIC OCEAN 

NWS OCEAN PREDICTION CENTER WASHINGTON DC

135 AM PDT THU 25 AUG 2016 



.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT 

.WEATHER FOR THE NORTH PACIFIC N OF 30N AND E OF 150W. 



0500Z AND 0540Z ASCAT OVERPASSES ACROSS THE OFFSHORE WATERS 

INDICATED HIGHEST WINDS TO 25 KT OVER OUTER PZ5 WATERS N OF 43N. 

ELSEWHERE WERE ALSO 25 KT RETURNS INVOF THE CHANNEL ISLANDS BUT 

WERE LIMITED TO THE COASTAL ZONES. 00Z MODELS WERE WELL 

INITIALIZED WITH WINDS ACROSS THE PZ5 AND NRN PZ6 WATERS...BUT 

WERE SLIGHTLY DEFICIENT WITH THE AFOREMENTIONED 25 KT NEAR THE 

CHANNEL ISLANDS. ACROSS THE IMMEDIATE OFFSHORE AND COASTAL ZONES 

THE 00Z MODELS ARE IN ABOVE AVERAGE AGREEMENT FOR THE NEXT FEW 

DAYS. STRONG HIGH PRES NEAR 49N141W SHOULD CONTINUE TO MIGRATE 

WESTWARD WHILE WEAKENING...WHILE LATEST GUIDANCE ALL INDICATE 

THAT WEAK LOW PRES SHOULD DEVELOP ALONG THE NRN CA COAST LATE 

TODAY/TONIGHT AND SLOWLY DRIFT SSW ACROSS PZ6 WATERS FRI THROUGH 

 SAT NIGHT BEFORE DISSIPATING SUN. WITH WEAKENING E PACIFIC HIGH 

PRES AND THIS WEAK LOW DEVELOPMENT SHOULD SEE A DIMINISHING 

TREND WITH THE OFFSHORE WINDS OVER THE WEEKEND. 



ALTHOUGH THERE ARE THEN TIMING DIFFERENCES WITH A MID/UPPER 

LEVEL TROF DROPPING S AND APPROACHING THE PZ5 WATERS 

FRI/SAT...AT THE SURFACE MODELS ARE SIMILAR IN DEPICTING A 

DEVELOPING SURFACE LOW WILL MOVE SSE NEAR VANCOUVER ISLAND WITH 

AN ASSOCITED NW SURGE DROPPING S INTO NRN PZ5 WATERS FRI NIGHT 

INTO SAT. PLAN TO KEEP OPC CONTINUITY WHICH FAVORED THE SLIGHTLY 

HIGHER GFS WITH WINDS BRIEFLY TO 30 KT N OF CAPE SHOALWATER FRI 

NIGHT. WILL BE POPULATING WITH THE 00Z GFS 10M WINDS THROUGH SAT 

NIGHT. BY SUN THROUGH EARLY NEXT WEEK MODELS ALL SHOW A WEAK 

COLD FRONT WILL APPROACH AND MOVE SE ACROSS THE PZ5 WATERS. 

LATEST GFS LOOKS A BIT SUSPECT IN DEVELOPING MULTIPLE WEAK LOWS 

ALONG THE FRONT SUN/MON. 00Z ECMWF TIMING IS BETTER SUPPORTED BY 

00Z GEFS. AM THEN FAVORING THE 00Z ECMWF SUN THROUGH EARLY NEXT 

WEEK.       



THE 00Z WAVEWATCH III WAS WELL INITIALIZED WITH E PACIFIC WAVE 

HEIGHTS AT 06Z. THE 00Z ECMWF WAM APPEARS A COUPLE FT TOO HIGH 

ACROSS OUTER PZ5 WATERS...YET HAS SLIGHLTLY BETTER HANDLE ON 

SEAS OFF S CA. A 50/50 BLEND OF THE ABOVE GUIDANCE LOOKS 

REPRESENTATIVE FOR TODAY...THEN TRANSITIONED TO 00Z WW3 THROUGH 

SAT NIGHT. WITH PREFERENCE FOR ECMWF BEGINNING SUN POPULATED 

WITH 00Z ECMWF WAM SUN THROUGH THE REMAINDER OF THE FORECAST 

PERIOD.  



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



.WARNINGS...PRELIMINARY. 



.PZ5 WASHINGTON/OREGON WATERS... 

     NONE. 



.PZ6 CALIFORNIA WATERS... 

     NONE. 



$$ 



.FORECASTER CLARK. OCEAN PREDICTION CENTER.

