


High Seas Forecast
Issued by NWS
Issued by NWS
395 FZPN02 KWBC 171725 HSFEPI HIGH SEAS FORECAST FOR METAREA XII NWS OCEAN PREDICTION CENTER WASHINGTON DC 1745 UTC SUN AUG 17 2025 CCODE/1:31:12:01:00/AOW+POR/NWS/CCODE SUPERSEDED BY NEXT ISSUANCE IN 6 HOURS SEAS GIVEN AS SIGNIFICANT WAVE HEIGHT...WHICH IS THE AVERAGE HEIGHT OF THE HIGHEST 1/3 OF THE WAVES. INDIVIDUAL WAVES MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT. ONLY YOU KNOW THE WEATHER AT YOUR POSITION. REPORT IT TO THE NATIONAL WEATHER SERVICE. EMAIL US AT VOSOPS@NOAA.GOV(LOWERCASE). FOR ANY TROPICAL CYCLONE INFORMATION BEYOND 48 HOURS REFERENCE THE ASSOCIATED NWS TROPICAL CYCLONE FORECAST/ADVISORY (TCM). SECURITE PACIFIC N OF 30N AND S OF 67N E OF A LINE FROM BERING STRAIT TO 50N 160E ALL FORECASTS VALID OVER ICE FREE FORECAST WATERS SYNOPSIS VALID 1200 UTC AUG 17. 24 HOUR FORECAST VALID 1200 UTC AUG 18. 48 HOUR FORECAST VALID 1200 UTC AUG 19. .WARNINGS. .NONE. .SYNOPSIS AND FORECAST. .LOW 57N143W 1002 MB MOVING S 20 KT. BETWEEN 180 NM AND 480 NM W QUADRANT...ALSO WITHIN 600 NM SW QUADRANT WINDS 20 TO 30 KT. SEAS 2 TO 3.5 M. .24 HOUR FORECAST LOW 49N133W 1009 MB. CONDITIONS DIMINISHED. .24 HOUR FORECAST LOW NW OF AREA 53N159E 1002 MB. N OF 50N BETWEEN 169E AND 164E WINDS TO 25 KT. SEAS LESS THAN 2.5 M. .48 HOUR FORECAST LOW NW OF AREA 58N165E 1005 MB. N OF 52N BETWEEN 176E AND 171E WINDS TO 25 KT. SEAS LESS THAN 2.5 M. .KLYUCHEVSKOY VOLCANO 56.03N 160.38E HAS ERUPTED. VOLCANIC ASH MAY BE REACHING THE SURFACE. MARINERS SHOULD EXERCISE CAUTION. IF MARINERS ENCOUNTER VOLCANIC ASH OR FLOATING VOLCANIC DEBRIS IN AND NEAR VICINITY YOU ARE ENCOURAGED TO REPORT THE OBSERVATION TO THE OCEAN PREDICTION CENTER BY CALLING 301-683-1520. .DENSE FOG. VSBY OCCASIONALLY LESS THAN 1 NM FROM 44N TO 55N BETWEEN 162W AND 174E...ALSO BETWEEN 43N AND 46N W OF 161E. .24 HOUR FORECAST DENSE FOG FROM 47N TO 55N BETWEEN 158W AND 179W...AND N OF 44N W OF 166E. .48 HOUR FORECAST DENSE FOG FROM 46N TO 50N BETWEEN 151W AND 158W...AND N OF 44N BETWEEN 172E AND 166E. .FORECASTER SHAW. OCEAN PREDICTION CENTER. NATIONAL HURRICANE CENTER MIAMI FL E PACIFIC FROM THE EQUATOR TO 30N E OF 140W AND 03.4S TO THE EQUATOR E OF 120W SYNOPSIS VALID 1200 UTC SUN AUG 17. 24 HOUR FORECAST VALID 1200 UTC MON AUG 18. 48 HOUR FORECAST VALID 1200 UTC TUE AUG 19. .WARNINGS. .NONE. .SYNOPSIS AND FORECAST. .WITHIN 09N134W TO 09N140W TO 04N140W TO 05N135W TO 06N133W TO 09N134W WINDS 20 KT OR LESS. SEAS 2.5 TO 3.0 M IN SE SWELL. .18 HOUR FORECAST CONDITIONS IMPROVE. WINDS 20 KT OR LESS. SEAS LESS THAN 2.5 M. .WITHIN 02S101W TO 00N114W TO 00N120W TO 03.4S120W TO 03.4S101W TO 02S101W WINDS 20 KT OR LESS. SEAS 2.5 TO 3.0 M IN S TO SW SWELL. .24 HOUR FORECAST WITHIN 00N99W TO 01S115W TO 03.4S120W TO 03.4S95W TO 00N99W WINDS 20 KT OR LESS. SEAS 2.5 TO 3.0 M IN SE TO S SWELL. .48 HOUR FORECAST WITHIN 01S103W TO 00N114W TO 01S120W TO 03.4S120W TO 03.4S98W TO 01S103W WINDS 20 KT OR LESS. SEAS 2.5 TO 3.0 M IN SE TO S SWELL. .30 HOUR FORECAST WITHIN 08N110W TO 05N115W TO 03N114W TO 03N113W TO 04N110W TO 08N110W WINDS 20 KT OR LESS. SEAS 2.5 TO 3.0 M IN S TO SW SWELL. .48 HOUR FORECAST WITHIN 08N109W TO 08N112W TO 07N113W TO 05N113W TO 03N112W TO 04N110W TO 08N109W WINDS 20 KT OR LESS. SEAS 2.5 TO 3.0 M IN S SWELL. .REMAINDER OF AREA WINDS 20 KT OR LESS. SEAS LESS THAN 2.5 M. CONVECTION VALID AT 1430 UTC SUN AUG 17... .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH FROM 09N84W TO 10N107W TO 14N118W TO 13N126W. ITCZ FROM 13N126W TO 10N140W. SCATTERED MODERATE ISOLATED STRONG FROM 04N TO 10N BETWEEN 80W AND 110W...FROM 06N TO 13N BETWEEN 112W AND 119W...AND FROM 10N TO 15N BETWEEN 123W AND 140W. $$ .FORECASTER AL. NATIONAL HURRICANE CENTER. NATIONAL WEATHER SERVICE HONOLULU HI NORTH PACIFIC EQUATOR TO 30N BETWEEN 140W AND 160E SYNOPSIS VALID 1200 UTC AUG 17 2025. 24 HOUR FORECAST VALID 1200 UTC AUG 18 2025. 48 HOUR FORECAST VALID 1200 UTC AUG 19 2025. .WARNINGS. .NONE. .SYNOPSIS AND FORECAST. .TROUGH 30N167W 25N169N NEARLY STATIONARY. NUMEROUS STRONG TSTMS N OF 26N BETWEEN 172W AND 163W. .24 HOUR FORECAST TROUGH 30N168W 25N168W. .48 HOUR FORECAST TROUGH 30N171W 26N173W. .TROUGH 30N178E 25N176E NEARLY STATIONARY. ISOLATED MODERATE TSTMS WITHIN 180 NM OF TROUGH. .24 HOUR FORECAST TROUGH 30N175E 25N172E. .48 HOUR FORECAST TROUGH 30N174E 25N172E. .TROUGH 28N165E 21N160E MOVING NW 10 KT. ISOLATED MODERATE TSTMS WITHIN 330 NM E OF TROUGH... AND WITHIN 180 NM W OF TROUGH W OF 163E. .24 HOUR FORECAST TROUGH 30N163E 24N160E. .48 HOUR FORECAST TROUGH 30N163E 27N160E. .TROUGH 24N152W 18N150W MOVING W 10 KT. .24 HOUR FORECAST TROUGH 22N157W 19N157W. .48 HOUR FORECAST TROUGH DISSIPATED. .SEAS 2.5 TO 3 M FROM 10N TO 17N BETWEEN 160W AND 145W. .24 HOUR FORECAST SEAS DIMINISHED TO 2.5 M OR LESS. .WINDS 20 KT OR LESS AND SEAS 2.5 M OR LOWER OVER REMAINDER OF FORECAST AREA. .ITCZ 10N140W 10N160W 06N174W 03N170E. SCATTERED MODERATE TSTMS WITHIN 180 NM N OF ITCZ BETWEEN 158W AND 153W. ISOLATED MODERATE TSTMS ELSEWHERE WITHIN 90 NM S OF ITCZ W OF 155W. .ISOLATED MODERATE TSTMS FROM 02N TO 14N W OF 170E... AND FROM 10N TO 12N BETWEEN 172W AND 169W... AND N OF 29N BETWEEN 162E AND 165E. $$ .FORECASTER SHIGESATO. HONOLULU HI.