


Coastal Waters Forecast
Issued by NWS Tiyan, Guam
Issued by NWS Tiyan, Guam
049 FZMY50 PGUM 290719 CWFGUM Coastal Waters Forecast for the Mariana Islands National Weather Service Tiyan GU 519 PM ChST Fri Aug 29 2025 Marianas Waters out to 40 nautical miles PMZ150-292000- 519 PM ChST Fri Aug 29 2025 .Synopsis for Marianas Waters...Gentle to moderate east- southeasterlies, along with gusty conditions within showers, are expected through the weekend. Combined seas of 5 to 7 feet are expected to taper down a foot over the weekend, to then diminish another 2 feet by midweek as trade swell and wind waves diminish. $$ PMZ151>154-292000- MARIANAS COASTAL WATERS- 519 PM ChST Fri Aug 29 2025 .TONIGHT...East wind 10 to 15 kt. Seas 5 to 7 ft. Wave Detail: East 6 ft at 8 seconds and east 3 ft at 4 seconds. Scattered showers with isolated thunderstorms. .SATURDAY...Southeast wind 5 to 15 kt wih occasional gusts to 25 kt near heavier showers. Seas 5 to 7 ft. Wave Detail: East 6 ft at 8 seconds and southeast 3 ft at 4 seconds. Numerous showers with isolated thunderstorms. Locally heavy showers possible. .SATURDAY NIGHT...Southeast wind 10 to 20 kt with gusts to 30 kt near heavier showers. Seas 5 to 6 ft. Wave Detail: East 6 ft at 8 seconds and southeast 4 ft at 4 seconds. Numerous heavy showers with isolated thunderstorms. .SUNDAY...Southeast wind 5 to 10 kt. Seas around 6 ft. Wave Detail: Southeast 6 ft at 8 seconds and south 2 ft at 4 seconds. Scattered showers with isolated thunderstorms. .SUNDAY NIGHT...Southeast wind 5 to 10 kt. Seas 4 to 5 ft. Wave Detail: East 5 ft at 8 seconds and southeast 2 ft at 4 seconds. Scattered showers. .MONDAY THROUGH WEDNESDAY...Southeast wind 5 to 15 kt. Seas 3 to 5 ft. Wave Detail: East 4 ft at 8 seconds and southeast 3 ft at 4 seconds. A chance of showers with a slight chance of thunderstorms. $$