123
FZPN40 PHFO 181520
HSFNP

HIGH SEAS FORECAST
NATIONAL WEATHER SERVICE HONOLULU HI
1700 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SUPERSEDED BY NEXT ISSUANCE IN 6 HOURS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 1200 UTC AUG 18 2025.
24 HOUR FORECAST VALID 1200 UTC AUG 19 2025.
48 HOUR FORECAST VALID 1200 UTC AUG 20 2025.

.WARNINGS.


.NONE.

.SYNOPSIS AND FORECAST.

.TROUGH 30N167W 26N171N NEARLY STATIONARY. SCATTERED MODERATE
TSTMS N OF 25N BETWEEN 171W AND 164W.
.24 HOUR FORECAST TROUGH 30N172W 26N173W.
.48 HOUR FORECAST TROUGH 30N174W 26N174W.

.TROUGH 30N174E 26N173E MOVING W 10 KT. SCATTERED MODERATE TSTMS
FROM 25N TO 27N BETWEEN 171E AND 176E.
.24 HOUR FORECAST TROUGH 30N168E 26N165E.
.48 HOUR FORECAST TROUGH DISSIPATED.

.TROUGH 26N157W 22N156W MOVING W 20 KT.
.24 HOUR FORECAST TROUGH 25N163W 22N162W.
.48 HOUR FORECAST TROUGH DISSIPATED.

.24 HOUR FORECAST NEW TROUGH 11N155W 05N158W. WINDS 20 TO 25 KT
WITHIN 60 NM OF TROUGH N OF 09N.
.48 HOUR FORECAST TROUGH 12N162W 07N163W. WINDS 20 TO 25 KT WITHIN
90 NM OF TROUGH N OF 10N.

.SEAS 2.5 TO 3 M FROM 10N TO 14N BETWEEN 155W AND 150W.
.24 HOUR FORECAST SEAS DIMINISHED TO 2.5 M OR LESS.
.48 HOUR FORECAST SEAS 2.5 M TO 3 M FROM 10N TO 15N BETWEEN 163W AND
158W.

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

.ITCZ 10N140W 10N165W 05N177E. ISOLATED MODERATE TSTMS WITHIN 210 NM
OF ITCZ..ISOLATED MODERATE TSTMS FROM 04N TO 08N W OF 165E.

.SCATTERED MODERATE TSTMS N OF 25N BETWEEN 163E AND 168E... AND
FROM 02N TO 07N BETWEEN 170E AND 177E. ISOLATED MODERATE TSTMS
FROM 03N TO 10N W OF 164E... AND FROM 20N TO 24N W OF 163E.

$$

.FORECASTER SHIGESATO. HONOLULU HI.