327
FZMY50 PGUM 010727
CWFGUM

Coastal Waters Forecast for the Mariana Islands
National Weather Service Tiyan GU
527 PM ChST Tue Sep 1 2026

Marianas Waters out to 40 nautical miles

PMZ150-012245-
527 PM ChST Tue Sep 1 2026

.Synopsis for Marianas Waters...
Combined seas of 5 to 6 feet will continue to gradually rise
through at least Thursday night, reaching as high as 8 to 9 feet
due to a strengthening west or southwesterly monsoon surge. Light
to gentle winds may increase significantly Thursday with maximum
sustained winds of 25 knots and gusts up to 30 knots. Therefore,
seas may also reach near criteria hazardous to small craft by
Thursday. The monsoon surge will bring the potential for locally
heavy showers and isolated thunderstorms through at least Thursday
night.

$$

PMZ151>154-012245-
MARIANAS COASTAL WATERS-
527 PM ChST Tue Sep 1 2026

.TONIGHT...Northwest wind 5 to 10 kt in the evening becoming light.
Seas 5 to 6 ft. Wave Detail: West 5 ft at 9 seconds, northeast 2
ft at 10 seconds, and northwest 2 ft at 4 seconds. Scattered
showers after midnight. Isolated thunderstorms.
.WEDNESDAY...Northwest wind 5 to 10 kt. Seas 5 to 6 ft. Wave
Detail: West 5 ft at 9 seconds, northeast 2 ft at 10 seconds, and
northwest 2 ft at 4 seconds. Scattered, locally heavy showers
with isolated thunderstorms.
.WEDNESDAY NIGHT...West wind 10 to 15 kt. Seas 5 to 7 ft. Wave
Detail: West 6 ft at 9 seconds and west 3 ft at 4 seconds.
Scattered, locally heavy showers with isolated thunderstorms.
.THURSDAY...Southwest wind 15 to 25 kt with gusts to 30 kt. Seas
7 to 9 ft. Wave Detail: Southwest 8 ft at 9 seconds and southwest
5 ft at 5 seconds. Scattered, locally heavy showers with isolated
thunderstorms.
.THURSDAY NIGHT...Southwest wind 15 to 25 kt with gusts to 30 kt.
Seas 7 to 9 ft. Wave Detail: Southwest 8 ft at 9 seconds and
southwest 5 ft at 6 seconds. Scattered, locally heavy showers with
isolated thunderstorms.
.FRIDAY...Southwest wind 15 to 25 kt. Seas 6 to 8 ft. Wave
Detail: West 7 ft at 9 seconds and southwest 5 ft at 6 seconds. A
slight chance of thunderstorms.
.SATURDAY...Southwest wind 10 to 15 kt. Seas 5 to 7 ft. Wave
Detail: West 6 ft at 8 seconds and southwest 3 ft at 4 seconds. A
chance of showers with a slight chance of thunderstorms.
.SUNDAY...West wind 5 to 10 kt. Seas 5 to 6 ft. Wave Detail: West
6 ft at 8 seconds and west 2 ft at 4 seconds. A chance of showers
with a slight chance of thunderstorms.

$$