412
FZPN40 PHFO 011453
HSFNP

HIGH SEAS FORECAST
NATIONAL WEATHER SERVICE HONOLULU HI
1700 UTC FRI AUG 01 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SUPERSEDED BY NEXT ISSUANCE IN 6 HOURS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 01 2025.
24 HOUR FORECAST VALID 1200 UTC AUG 02 2025.
48 HOUR FORECAST VALID 1200 UTC AUG 03 2025.

.WARNINGS.

...TROPICAL STORM WARNING...
.TROPICAL STORM IONA NEAR 14.4N 175.5W 1005 MB AT 1200 UTC AUG 01
MOVING WNW OR 285 DEG AT 18 KT. MAXIMUM SUSTAINED WINDS 35 KT
GUSTS 45 KT. TROPICAL STORM FORCE WINDS WITHIN 50 NM NE QUADRANT
AND 40 NM NW QUADRANT. SEAS 4 M OR GREATER WITHIN 210 NM NE
QUADRANT... 90 NM SE QUADRANT... 50 NM SW QUADRANT... 120 NM NW
QUADRANT. SEAS 2.5 TO 4 M ELSEWHERE FROM 10N TO 22N BETWEEN 177W
AND 163W. WINDS 20 TO 33 KT ELSEWHERE FROM 10N TO 20N BETWEEN 177W
AND 170W.
.24 HOUR FORECAST TROPICAL STORM IONA NEAR 16.6N 178.8E. MAXIMUM
SUSTAINED WINDS 35 KT GUSTS 45 KT. TROPICAL STORM FORCE WINDS
WITHIN 50 NM NE QUADRANT AND 40 NM NW QUADRANT. SEAS 4 M OR GREATER
WITHIN 30 NM OF CENTER. SEAS 2.5 M TO 4 M ELSEWHERE FROM 15N TO
22N BETWEEN 175E AND 175W. WINDS 20 TO 33 KT ELSEWHERE FROM 15N TO
20N BETWEEN 177E AND 177W.
.48 HOUR FORECAST TROPICAL DEPRESSION IONA NEAR 19.0N 174.3E.
MAXIMUM SUSTAINED WINDS 30 KT GUSTS 40 KT. SEAS 2.5 M TO 4 M FROM
18N TO 24N BETWEEN 170E AND 177E. WINDS 20 TO 33 KT ELSEWHERE FROM
15N TO 20N BETWEEN 172E AND 177E.

SEE BULLETIN TCMCP1 ISSUED BY CPHC FOR MORE INFORMATION

FORECAST WINDS IN AND NEAR ACTIVE TROPICAL CYCLONES SHOULD BE
USED WITH CAUTION DUE TO UNCERTAINTY IN FORECAST TRACK...SIZE AND
INTENSITY.

.SYNOPSIS AND FORECAST.

.TROUGH NEAR 14N154W 10N154W MOVING W 10 KT. WINDS 20 TO 25 KT
FROM 11N TO 15N BETWEEN 160W AND 150W. SEAS 2.5 TO 3 M FROM 10N
TO 20N BETWEEN 160W AND 145W. ISOLATED MODERATE TSTMS WITHIN 120
NM OF TROUGH.
.24 HOUR FORECAST TROUGH 12N160W 09N160W MOVING W SLOWLY. WINDS
20 TO 25 KT FROM 11N TO 17N BETWEEN 165W AND 157W. SEAS 2.5 TO 3 M
FROM 10N TO 15N BETWEEN 163W AND 155W.
.48 HOUR FORECAST TROUGH 11N1637 08N166W. WINDS 20 TO 25 KT FROM
10N TO 15N BETWEEN 165W AND 160W.

.24 HOUR FORECAST NEW TROUGH 30N170E 26N165E. WINDS 20 TO 25 KT N
OF 26N BETWEEN TROUGH AND 177E. SEAS 2.5 TO 3 M N OF 28N BETWEEN
170E AND 174E.
.48 HOUR FORECAST TROUGH 30N171E 25N167E. WINDS 20 TO 25 KT WITHIN
150 NM E OF TROUGH. SEAS DISSIPATED TO 2.5 M OR LESS.

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

.ITCZ 07N140W 08N147W...AND 08N155W 06N165W 08N170W 06N161E.
ISOLATED MODERATE TSTMS WITHIN 240 NM OF ITCZ W OF 155W.

.SCATTERED MODERATE TSTMS N OF 26N BETWEEN 174W AND 170W... AND N
OF 27N BETWEEN 178E AND 177W. ISOLATED MODERATE TSTMS FROM 18N TO
21N BETWEEN 177W AND 172W... AND N OF 28N BETWEEN 163E AND 168E.

$$

.FORECASTER SHIGESATO. HONOLULU HI.