918
FZPN40 PHFO 212159
HSFNP

HIGH SEAS FORECAST
NATIONAL WEATHER SERVICE HONOLULU HI
2300 UTC THU AUG 21 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SUPERSEDED BY NEXT ISSUANCE IN 6 HOURS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 1800 UTC AUG 21 2025.
24 HOUR FORECAST VALID 1800 UTC AUG 22 2025.
48 HOUR FORECAST VALID 1800 UTC AUG 23 2025.

.WARNINGS.

.NONE.

.SYNOPSIS AND FORECAST.

.TROUGH 30N173E 26N173E MOVING NW SLOWLY. ISOLATED MODERATE TSTMS
WITHIN 120 NM OF TROUGH.
.24 HOUR FORECAST TROUGH MOVED N OF AREA.

.TROUGH 30N177E 27N177E 23N178E MOVING NW 10 KT. ISOLATED
MODERATE TSTMS WITHIN 270 NM E OF TROUGH.
.24 HOUR FORECAST TROUGH 30N173E 25N169E.
.48 HOUR FORECAST TROUGH 30N168E 26N165E.

.TROUGH 29N170W 27N171W 25N171W MOVING NW SLOWLY. ISOLATED
MODERATE TSTMS 120 NM W OF TROUGH AND 210 NM E OF TROUGH.
.24 HOUR FORECAST TROUGH DISSIPATED.

.TROUGH 22N163E 18N161E NEARLY STATIONARY. ISOLATED MODERATE
TSTMS WITHIN 60 NM OF TROUGH.
.24 HOUR FORECAST TROUGH DISSIPATED.

.WINDS 20 TO 25 KT FROM 16N TO 11N BETWEEN 174W AND 162W...AND
FROM 19N TO 13N E OF 153W.
.24 HOUR FORECAST WINDS 20 TO 25 KT FROM 18N TO 13N E OF 157W.
.48 HOUR FORECAST WINDS 20 TO 25 KT FROM 19N TO 14N E BETWEEN 153W
AND 144W.

.SEAS 2.5 TO 3 M FROM 16N TO 11N BETWEEN 173W AND 163W...AND FROM
18N TO 14N E OF 154W.
.24 HOUR FORECAST SEAS 2.5 TO 3 M FROM 17N TO 11N BETWEEN 179W AND
170W...AND FROM 20N TO 13N E OF 158W.
.48 HOUR FORECAST SEAS 2.5 TO 3 M FROM 17N AND 13N BETWEEN 173E
AND 179W...AND FROM 21N TO 13N BETWEEN 162W AND 141W.

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

.MONSOON TROUGH 12N140W 12N147W THENCE ITCZ 10N156W 10N169W
05N171E 07N160E. ISOLATED MODERATE TSTMS WITHIN 210 NM OF TROUGH
AND ITCZ BETWEEN 167E AND 179E...BETWEEN 171W AND 157W...AND E OF
152W.

.ISOLATED MODERATE TSTMS FROM 27N TO 22N W OF 163E.

$$

.FORECASTER PIERCE. HONOLULU HI.