The High Seas Forecast for the Central North Pacific

High Seas Forecast Issued: 08/18/2025 12:57:02 PM UTC
                        
863
FZPN40 PHFO 180257
HSFNP

HIGH SEAS FORECAST
NATIONAL WEATHER SERVICE HONOLULU HI
0500 UTC MON AUG 18 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SUPERSEDED BY NEXT ISSUANCE IN 6 HOURS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 0000 UTC AUG 18 2025.
24 HOUR FORECAST VALID 0000 UTC AUG 19 2025.
48 HOUR FORECAST VALID 0000 UTC AUG 20 2025.

.WARNINGS.

.NONE.

.SYNOPSIS AND FORECAST.

.TROUGH 30N168W 26N170N NEARLY STATIONARY. ISOLATED MODERATE TSTMS
N OF 28N BETWEEN 172W AND 164W.
.24 HOUR FORECAST TROUGH 30N170W 25N173W.
.48 HOUR FORECAST TROUGH 30N172W 24N176W.

.TROUGH 30N177E 26N175E NEARLY STATIONARY.
.24 HOUR FORECAST TROUGH 30N171E 25N170E.
.48 HOUR FORECAST TROUGH 30N170E 25N168E.

.TROUGH 30N162E 26N160E MOVING NW 10 KT. ISOLATED MODERATE TSTMS
N OF 25N AND W OF 168E.
.24 HOUR FORECAST TROUGH 30N163E 25N160E.
.48 HOUR FORECAST TROUGH 30N161E 28N160E.

.TROUGH 27N155W 22N155W MOVING W 10 KT.
.24 HOUR FORECAST TROUGH 27N155W 20N155W.
.48 HOUR FORECAST TROUGH DISSIPATED.

.SEAS 2.5 TO 3 M FROM 09N TO 18N BETWEEN 166W AND 143W.
.24 HOUR FORECAST SEAS DIMINISHED TO 2.5 M OR LESS.
.48 HOUR FORECAST SEAS 2.5 M TO 3 M FROM 11N TO 15N BETWEEN 153W AND 164W.

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

.ITCZ 10N140W 10N153W 06N170W 05N180E. SCATTERED MODERATE TSTMS WITHIN
210 NM N OF ITCZ E OF 170W.

.SCATTERED MODERATE TSTMS FROM 05N TO 10N W OF 163E.

$$

.FORECASTER M BALLARD. HONOLULU HI.