307
FZMY50 PGUM 150715
CWFGUM

Coastal Waters Forecast for the Mariana Islands
National Weather Service Tiyan GU
515 PM ChST Wed Oct 15 2025

Marianas Waters out to 40 nautical miles

PMZ150-152200-
515 PM ChST Wed Oct 15 2025

.Synopsis for Marianas Waters...Moderate to Fresh easterlies with
strong gusts possible are expected in Guam and Rota waters
through late tonight while remaining moderate to fresh at Tinian
and Saipan as Invest 96W passes by to the southwest of Guam
tonight. Combined seas of 6 to 8 feet near Guam and Rota, and 5 to
7 feet near Tinian and Saipan, will diminish 1 to 2 feet by
Thursday. Over the weekend, seas are expected to fall to 4 to 6
feet. Showers and thunderstorms, primarily across Guam and Rota
waters, will persist through tonight.

$$

PMZ151-152-152200-
Guam Coastal Waters-Rota Coastal Waters-
515 PM ChST Wed Oct 15 2025

...SMALL CRAFT ADVISORY HAS BEEN CANCELLED...

.TONIGHT...East wind 15 to 20 kt with gusts to 30 kt. Seas 6 to
8 ft. Wave Detail: East 6 ft at 8 seconds and east 4 ft at
5 seconds, and northeast 2 ft at 12 seconds. Numerous becoming
scattered showers around midnight with isolated thunderstorms.
.THURSDAY...East wind 10 to 15 kt. Seas 4 to 6 ft. Wave Detail:
Northeast 6 ft at 8 seconds, east 3 ft at 5 seconds and east 2 ft
at 12 seconds. Isolated thunderstorms.
.THURSDAY NIGHT...East wind 10 to 15 kt. Seas 4 to 6 ft. Wave
Detail: Northeast 4 ft at 8 seconds, east 3 ft at 4 seconds and
east 2 ft at 12 seconds. Isolated thunderstorms.
.FRIDAY...East wind 15 kt. Seas 4 to 6 ft. Wave Detail: Northeast
4 ft at 9 seconds, east 3 ft at 5 seconds and northeast 2 ft at
12 seconds.
.FRIDAY NIGHT...East wind 15 kt. Seas 4 to 6 ft. Wave Detail:
Northeast 4 ft at 9 seconds, east 3 ft at 4 seconds, and east 2
ft at 12 seconds.
.SATURDAY...East wind 15 kt. Seas 4 to 6 ft. Wave Detail:
Northeast 4 ft at 10 seconds, east 3 ft at 5 seconds , and east 2
ft at 12 seconds. Scattered showers with a slight chance of
thunderstorms.
.SUNDAY...East wind 15 kt. Seas 4 to 6 ft. Wave Detail: Northeast
4 ft at 8 seconds, east 3 ft at 5 seconds, and northeast 2 ft at
12 seconds. A slight chance of thunderstorms.
.MONDAY...East wind 10 to 15 kt. Seas 5 to 6 ft. Wave Detail:
Northeast 4 ft at 9 seconds, east 2 ft at 4 seconds and northeast
2 ft at 13 seconds. A chance of showers with a slight chance of
thunderstorms.

$$

PMZ153-154-152200-
Tinian Coastal Waters-Saipan Coastal Waters-
515 PM ChST Wed Oct 15 2025

.TONIGHT...East wind 10 to 15 kt. Seas 5 to 7 ft. Wave Detail:
Northeast 5 ft at 9 seconds, east 3 ft at 4 seconds, and east 2
ft at 12 seconds. Scattered showers with isolated thunderstorms.
.THURSDAY...East wind 10 to 15 kt. Seas 4 to 6 ft. Wave Detail:
Northeast 5 ft at 8 seconds, east 3 ft at 5 seconds and east 3 ft
at 12 seconds. Isolated thunderstorms.
.THURSDAY NIGHT...East wind 15 kt. Seas 5 to 6 ft. Wave Detail:
Northeast 5 ft at 9 seconds, east 3 ft at 5 seconds and east 2 ft
at 12 seconds. Isolated thunderstorms.
.FRIDAY...East wind 15 kt. Seas 4 to 6 ft. Wave Detail: Northeast
4 ft at 9 seconds, east 3 ft at 5 seconds and east 2 ft at 12
seconds.
.FRIDAY NIGHT...East wind 15 kt. Seas 4 to 6 ft. Wave Detail:
Northeast 4 ft at 9 seconds, east 3 ft at 5 seconds and east 2 ft
at 12 seconds.
.SATURDAY THROUGH SUNDAY...East wind 15 kt. Seas 4 to 6 ft. Wave
Detail: Northeast 4 ft at 9 seconds, east 3 ft at 5 seconds and
east 3 ft at 12 seconds. A slight chance of thunderstorms.
.MONDAY...East wind 10 to 15 kt. Seas 5 to 7 ft. Wave Detail:
Northeast 5 ft at 9 seconds, east 3 ft at 4 seconds and east 2 ft
at 13 seconds. A chance of showers with a slight chance of
thunderstorms.

$$