Coastal Waters Forecast
Issued by NWS Tiyan, Guam
Issued by NWS Tiyan, Guam
456 FZMY50 PGUM 290706 CWFGUM Coastal Waters Forecast for the Mariana Islands National Weather Service Tiyan GU 506 PM ChST Sat Nov 29 2025 Marianas Waters out to 40 nautical miles PMZ150-292200- 506 PM ChST Sat Nov 29 2025 .Synopsis for Marianas Waters... Moderate to fresh trades will prevail across the region through next Wednesday, as a tropical disturbance is expected to bring an increase in showers and gusts over the next few days. Trade convergence following this disturbance may prolong showers near Guam and Rota through the middle of this upcoming week. Combined seas of 5 to 7 feet are expected to build to 7 to 9 feet Sunday as northerly swell arrives, generated by a distant low pressure system. $$ PMZ151-152-292200- Guam Coastal Waters-Rota Coastal Waters- 506 PM ChST Sat Nov 29 2025 .TONIGHT...East wind 15 kt. Gusts to 25 kt near showers. Seas 5 to 7 ft. Wave Detail: East 6 ft at 9 seconds, east 3 ft at 5 seconds and north 2 ft at 12 seconds. Scattered showers becoming numerous late evening. Isolated thunderstorms. .SUNDAY...East wind 15 to 20 kt. Gusts to 30 kt near showers. Seas 7 to 9 ft. Wave Detail: East 6 ft at 9 seconds, east 5 ft at 6 seconds and north 4 ft at 12 seconds. Numerous showers with isolated thunderstorms. Locally heavy showers possible. .SUNDAY NIGHT...East wind 15 kt with gusts to 25 kt. Seas 6 to 8 ft. Wave Detail: East 5 ft at 9 seconds, north 5 ft at 15 seconds and east 4 ft at 5 seconds. Numerous showers with isolated thunderstorms. .MONDAY...Southeast wind 15 kt with gusts to 25 kt. Seas 6 to 8 ft. Wave Detail: North 5 ft at 14 seconds, east 5 ft at 9 seconds and southeast 4 ft at 5 seconds. Numerous showers with isolated thunderstorms. .MONDAY NIGHT...East wind 15 to 20 kt. Seas 7 to 9 ft. Wave Detail: North 5 ft at 13 seconds, east 4 ft at 6 seconds and east 5 ft at 9 seconds. Scattered showers with isolated thunderstorms. .TUESDAY...East wind 15 to 20 kt. Seas 6 to 8 ft. Wave Detail: East 6 ft at 9 seconds, northeast 4 ft at 13 seconds and east 3 ft at 5 seconds. Scattered showers with isolated thunderstorms. .WEDNESDAY...East wind 15 kt. Seas 7 to 9 ft. Wave Detail: East 7 ft at 9 seconds, east 3 ft at 5 seconds and northeast 3 ft at 13 seconds. A chance of showers. .THURSDAY...Southeast wind 10 to 15 kt. Seas 5 to 7 ft. Wave Detail: East 6 ft at 9 seconds, southeast 3 ft at 5 seconds and northeast 3 ft at 13 seconds. A chance of showers with a slight chance of thunderstorms. $$ PMZ153-154-292200- Tinian Coastal Waters-Saipan Coastal Waters- 506 PM ChST Sat Nov 29 2025 .TONIGHT...East wind 10 to 20 kt. Seas 5 to 8 ft. Wave Detail: East 6 ft at 9 seconds, east 4 ft at 5 seconds and north 2 ft at 11 seconds. Scattered showers in the evening, then numerous showers with isolated thunderstorms after midnight. .SUNDAY...East wind 15 to 20 kt. Seas 7 to 9 ft. Wave Detail: East 6 ft at 9 seconds, north 4 ft at 12 seconds and east 4 ft at 5 seconds. Numerous showers in the morning, then scattered showers in the afternoon. Isolated thunderstorms. .SUNDAY NIGHT...East wind 15 kt. Seas 6 to 8 ft. Wave Detail: East 6 ft at 9 seconds, north 5 ft at 15 seconds and east 3 ft at 5 seconds. Scattered showers with isolated thunderstorms. .MONDAY...East wind 15 kt. Seas 6 to 8 ft. Wave Detail: East 5 ft at 9 seconds, north 5 ft at 14 seconds and east 3 ft at 5 seconds. Scattered showers with isolated thunderstorms. .MONDAY NIGHT...East wind 15 to 20 kt. Seas 6 to 8 ft. Wave Detail: East 5 ft at 9 seconds, north 5 ft at 14 seconds and east 4 ft at 6 seconds. .TUESDAY...Southeast wind 15 to 20 kt. Seas 6 to 8 ft. Wave Detail: East 6 ft at 9 seconds, northeast 4 ft at 14 seconds and southeast 4 ft at 6 seconds. .WEDNESDAY...East wind 15 kt. Seas 7 to 9 ft. Wave Detail: East 7 ft at 9 seconds, east 3 ft at 5 seconds and northeast 3 ft at 13 seconds. .THURSDAY...Southeast wind 10 to 15 kt. Seas 5 to 7 ft. Wave Detail: East 6 ft at 9 seconds, southeast 3 ft at 5 seconds and northeast 3 ft at 13 seconds. A chance of showers. $$