


Coastal Waters Forecast
Issued by NWS Tiyan, Guam
Issued by NWS Tiyan, Guam
626 FZMY50 PGUM 230600 CWFGUM Coastal Waters Forecast for the Mariana Islands National Weather Service Tiyan GU 400 PM ChST Mon Jun 23 2025 Marianas Waters out to 40 nautical miles PMZ150-232100- 400 PM ChST Mon Jun 23 2025 .Synopsis for Marianas Waters...Light to gentle east to southeast trades will prevail through Wednesday. Winds look to become moderate to fresh and southerly towards the end of the week as a disturbance develops over the area. Increasing showers and thunderstorms are expected into the weekend. Combined seas of 3 to 5 feet will continue through much of the week, building to between 4 and 6 feet by the weekend. $$ PMZ151>154-232100- MARIANAS COASTAL WATERS- 400 PM ChST Mon Jun 23 2025 .TONIGHT...Southeast wind 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: East 3 ft at 8 seconds and southeast 2 ft at 4 seconds. Isolated thunderstorms. .TUESDAY...East wind 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: East 3 ft at 8 seconds and east 2 ft at 4 seconds. Isolated thunderstorms. .TUESDAY NIGHT...East wind 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: East 3 ft at 8 seconds and east 2 ft at 4 seconds. Scattered showers with isolated thunderstorms. .WEDNESDAY...East wind 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: East 3 ft at 8 seconds and east 2 ft at 4 seconds. Scattered showers with isolated thunderstorms. .WEDNESDAY NIGHT...Southeast wind 5 to 15 kt. Seas 3 to 5 ft. Wave Detail: East 4 ft at 8 seconds and southeast 3 ft at 4 seconds. Scattered showers with isolated thunderstorms. .THURSDAY...South wind 10 to 15 kt. Gusts to 25 kt with heavier showers and thunderstorms. Seas 3 to 5 ft. Wave Detail: East 4 ft at 8 seconds and southeast 3 ft at 4 seconds. Showers likely with a slight chance of thunderstorms. .FRIDAY THROUGH SATURDAY...Southwest wind 10 to 20 kt. Gusts to 35 kt with heavier showers and thunderstorms. Seas 4 to 6 ft. Wave Detail: East 5 ft at 8 seconds and southwest 4 ft at 6 seconds. Widespread locally heavy showers with a slight chance of thunderstorms. $$