518
FZHW60 PHFO 211530
OFFHFO

Offshore Waters Forecast for Hawaii
National Weather Service Honolulu HI
530 AM HST Fri Aug 21 2026

Hawaiian offshore waters beyond 40 nautical miles out to 240
nautical miles including the portion of the Papahanaumokuakea
Marine National Monument east of French Frigate Shoals

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.

PHZ105-212215-
530 AM HST Fri Aug 21 2026

.Synopsis for the Hawaiian offshore waters...
A weak trough will continue to move NW across the N offshore
waters through today before exiting the area. At 1500 UTC,
Tropical Depression Two-C was located at 13.4N 146.0W, moving WNW
at 9 kt. Two-C is expected to strengthen to a tropical storm and
track through the S offshore waters this weekend.

TWO-C FORECAST POSITIONS
200 PM HST FRIDAY    13.9N 147.2W
200 AM HST SATURDAY  14.7N 149.2W
200 PM HST SATURDAY  15.4N 151.3W
200 AM HST SUNDAY    15.9N 153.7W
200 PM HST SUNDAY    16.2N 156.3W
200 AM HST MONDAY    16.6N 159.1W
200 AM HST TUESDAY   17.7N 164.2W
200 AM HST WEDNESDAY 18.5N 168.4W
200 AM HST THURSDAY  18.8N 171.5W
200 AM HST FRIDAY    18.9N 175.0W

$$

PHZ180-212215-
Hawaiian Offshore Waters-
530 AM HST Fri Aug 21 2026

...TROPICAL STORM CONDITIONS POSSIBLE SATURDAY NIGHT INTO SUNDAY...

.TODAY...NW half, variable winds 5 to 15 kt. SE half, E to SE
winds 10 to 15 kt. Seas 5 to 7 ft.
.TONIGHT...N of 22N, E to SE winds 5 to 15 kt. Elsewhere, E winds
10 to 20 kt. Seas 6 to 9 ft.
.SATURDAY...NW half, E winds 10 to 20 kt. SE half, E winds 20 to
30 kt. Seas 6 to 9 ft, building to 6 to 11 ft in the afternoon.
Isolated thunderstorms SE Waters.
.SATURDAY NIGHT...Tropical storm conditions possible over SE
waters. Elsewhere, E winds 15 to 25 kt. Seas 6 to 15 ft. Isolated
thunderstorms SE Waters.
.SUNDAY...Tropical storm conditions possible S of 19N, W of 152W.
Elsewhere, E winds 15 to 25 kt. Seas 7 to 15 ft. Isolated
thunderstorms SE Waters.
.MONDAY...E winds 10 to 20 kt N of 20N, E 20 to 30 kt elsewhere.
Seas 6 to 10 ft. Isolated thunderstorms S of 24N.
.TUESDAY...E winds 10 to 20 kt. Seas 5 to 8 ft. Isolated
thunderstorms S of 23N.

$$