953
FZPN40 PHFO 311503
HSFNP

HIGH SEAS FORECAST
NATIONAL WEATHER SERVICE HONOLULU HI
1700 UTC THU JUL 31 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SUPERSEDED BY NEXT ISSUANCE IN 6 HOURS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 JUL 31 2025.
24 HOUR FORECAST VALID 1200 UTC AUG 01 2025.
48 HOUR FORECAST VALID 1200 UTC AUG 02 2025.

.WARNINGS.

...TROPICAL STORM WARNING...
.TROPICAL STORM IONA NEAR 12.7N 168.7W 1001 MB AT 1500 UTC JUL
31 MOVING W OR 280 DEG AT 18 KT. MAXIMUM SUSTAINED WINDS 45 KT
GUSTS 55 KT. TROPICAL STORM FORCE WINDS WITHIN 40 NM N
SEMICIRCLE AND 0 NM S SEMICIRCLE.
.24 HOUR FORECAST TROPICAL STORM IONA NEAR 14.0N 174.9W. MAXIMUM
SUSTAINED WINDS 35 KT GUSTS 45 KT. TROPICAL STORM FORCE WINDS
WITHIN 30 NM N SEMICIRCLE AND 0 NM S SEMICIRCLE. 4 M OR GREATER
150 NM OF CENTER WITH SEAS TO 5 M.
.48 HOUR FORECAST TROPICAL STORM IONA NEAR 14.7N 178.0W. MAXIMUM
SUSTAINED WINDS 35 KT GUSTS 45 KT. LITTLE CHANGE IN RADIUS OF
TROPICAL STORM FORCE WINDS AND SEAS 4 M OR GREATER.

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.

.LOW NEAR 11N149W 1010 MB MOVING W 10 KT. WINDS 20 TO 25 KT FROM
16N TO 12N BETWEEN 151W AND 145W. SEAS 2.5 TO 4 M FROM 19N TO 11N
BETWEEN 151W AND 142W.
.24 HOUR FORECAST LOW BECOMES TROUGH 13N153W 10N154W 09N154W.
WINDS 20 TO 25 KT FROM 15N TO 13N BETWEEN 157W AND 151W. SEAS 2.5
TO 4 M FROM 19N TO 11N BETWEEN 161W AND 142W.
.48 HOUR FORECAST TROUGH 13N160W 09N160W. WINDS 20 TO 25 KT FROM
16N TO 12N BETWEEN 164W AND 155W. SEAS 2.5 TO 4 M FROM 19N TO 12N
BETWEEN 165W AND 153W.

.TROUGH 30N148W 26N153W NEARLY STATIONARY.
.24 HOUR FORECAST TROUGH DISSIPATED.

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

.ITCZ 12N140W TO LOW NEAR 11N149W TO 07N153W 08N158W TO T.S. IONA
TO 07N179E 09N160E.

.ISOLATED MODERATE TSTMS N OF 25N BETWEEN 178E AND 160W.


$$

.FORECASTER PIERCE. HONOLULU HI.