FZPN40 PHFO 191531

HSFNP 



HIGH SEAS FORECAST

NATIONAL WEATHER SERVICE HONOLULU HI

1700 UTC TUE AUG 19 2025



SUPERSEDED BY NEXT ISSUANCE IN 6 HOURS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.



THIS HIGH SEAS FORECAST USES 1-MINUTE AVERAGE WINDS WHICH MAY BE

HIGHER THAN 10-MINUTE AVERAGE WINDS.



SECURITE



NORTH PACIFIC EQUATOR TO 30N BETWEEN 140W AND 160E



SYNOPSIS VALID 1200 UTC AUG 19 2025.

24 HOUR FORECAST VALID 1200 UTC AUG 20 2025.

48 HOUR FORECAST VALID 1200 UTC AUG 21 2025.



.WARNINGS.





.NONE.



.SYNOPSIS AND FORECAST. 



.TROUGH FROM 30N170W TO 26N174W MOVING NW SLOWLY. ISOLATED 

MODERATE TSTMS N OF 28N BETWEEN 1695W AND 172W E OF TROUGH.

.24 HOUR FORECAST TROUGH FROM 30N175W TO 27N179E.

.48 HOUR FORECAST TROUGH FROM 30N177W TO 27N179E.



.TROUGH FROM 30N174E TO 26N170E MOVING N SLOWLY. ISOLATED 

MODERATE TSTMS WITHIN 240 NM EITHER SIDE OF TROUGH N OF 26N.

.24 HOUR FORECAST TROUGH MOVED N OF AREA.



.TROUGH FROM 24N166E TO 25N161E MOVING E SLOWLY. SCATTERED 

MODERATE TSTMS WITHIN 90 NM EITHER ALONG TROUGH S OF 27N...AND 

WITHIN 240 NM W OF TROUGH N OF 27N. 

.24 HOUR FORECAST FROM 30N167E TO 23N160E. 

.48 HOUR FORECAST TROUGH DISSIPATED.



.TROUGH FROM 22N167W TO 17N162W NEARLY STATIONARY. 

.24 HOUR FORECAST TROUGH DISSIPATED. 



.24 HOUR FORECAST NEW TROUGH FROM 12N159W TO 09N160W. WINDS 20 TO

25 KT WITHIN 60 NM OF TROUGH N OF 10N.

.48 HOUR FORECAST TROUGH FROM 13N164W TO 05N167W. WINDS 20 TO 25 

KT WITHIN 90 NM OF TROUGH N OF 11N.



.SEAS 2.5 TO 3 M FROM 10N TO 13N BETWEEN 154W AND 158W.

.24 HOUR FORECAST SEAS 2.5 TO 3 M FROM 11N TO 16N BETWEEN 155W 

AND 164W.

.48 HOUR FORECAST SEAS 2.5 M TO 3 M FROM 11N TO 16N BETWEEN 158W 

AND 171W. 



.WINDS 20 KT OR LESS AND SEAS 2.5 M OR LOWER OVER REMAINDER OF 

FORECAST AREA.



.SCATTERED MODERATE TSTMS WITHIN 180 NM OF A LINE FROM 11N179W TO

04N160E. 



.MONSOON TROUGH FROM 10N150W TO 10N157W THENCE ITCZ TO 07N175E. 

ISOLATED MODERATE TSTMS WITHIN 150 NM N OF MONSOON TROUGH.

ISOLATED MODERATE TSTMS WITHIN 180 NM MAINLY S OF ITCZ .







$$



.FORECASTER BLOOD. HONOLULU HI.