FZMY50 PGUM 150039 CWFGUM Coastal Waters Forecast for the Mariana Islands National Weather Service Tiyan GU 1039 AM ChST Wed Apr 15 2026 Marianas Waters out to 40 nautical miles PMZ150-151015- 1039 AM ChST Wed Apr 15 2026 .Synopsis for Marianas Waters... The eye of Typhoon Sinlaku is moving north-northwest, away from Tinian and Saipan. Due to the large wind field around the system, life threatening marine conditions will persist through at least Thursday for Guam, Thursday evening for Rota, and Thursday night into Friday for Tinian and Saipan. In addition to winds, Sinlaku will produce heavy showers and isolated thunderstorms through tonight. Combined seas are expected to be around 15 to 24 ft for Guam, 24 to 30 feet for Rota, and 30 to 40 feet for Tinian and Saipan through Wednesday as Sinlaku moves through. $$ PMZ151-151015- Guam Coastal Waters- 1039 AM ChST Wed Apr 15 2026 ...TROPICAL STORM WARNING REMAINS IN EFFECT... ...TYPHOON WATCH REMAINS IN EFFECT... .TODAY...West tropical storm force wind to 40 kt with gusts to 60 kt. Seas 15 to 24 ft. Scattered showers late this morning. Isolated thunderstorms. .TONIGHT...Southwest tropical storm force wind to 35 kt with gusts to 50 kt. Seas 16 to 20 ft. .THURSDAY...Southwest wind 30 kt with gusts to 45 kt. Seas 13 to 17 ft. .THURSDAY NIGHT...Southwest wind 20 to 25 kt with gusts to 35 kt. Seas 12 to 15 ft. .FRIDAY...West wind 15 to 20 kt. Seas 9 to 12 ft. Wave Detail: Northwest 12 ft at 11 seconds and west 4 ft at 6 seconds. .SATURDAY...Southwest wind 10 to 15 kt. Seas 7 to 9 ft. Wave Detail: Northwest 9 ft at 10 seconds and west 3 ft at 4 seconds. .SUNDAY...Southwest wind 5 to 10 kt. Seas 5 to 7 ft. Wave Detail: North 7 ft at 10 seconds and southwest 2 ft at 4 seconds. $$ PMZ152-151015- Rota Coastal Waters- 1039 AM ChST Wed Apr 15 2026 ...TYPHOON WARNING IN EFFECT... .TODAY...Southwest tropical storm force wind to 55 kt with gusts to 75 kt. Seas 26 to 30 ft. Widespread showers and scattered thunderstorms. .TONIGHT...Southwest tropical storm force wind to 45 kt with gusts to 60 kt. Seas 21 to 25 ft. Scattered showers in the evening. Isolated thunderstorms. .THURSDAY...Southwest tropical storm force wind to 35 kt with gusts to 50 kt. Seas 18 to 20 ft. Isolated thunderstorms. .THURSDAY NIGHT...Southwest wind 20 to 25 kt with gusts to 35 kt. Seas 14 to 16 ft. .FRIDAY...Southwest wind 15 to 25 kt. Seas 11 to 14 ft. .SATURDAY...Southwest wind 10 to 15 kt. Seas 7 to 9 ft. Wave Detail: Northwest 9 ft at 10 seconds and southwest 3 ft at 5 seconds. .SUNDAY...Southwest wind 5 to 10 kt. Seas 6 to 8 ft. Wave Detail: North 7 ft at 10 seconds and southwest 2 ft at 4 seconds. $$ PMZ153-154-151015- Tinian Coastal Waters-Saipan Coastal Waters- 1039 AM ChST Wed Apr 15 2026 ...TYPHOON WARNING IN EFFECT... .TODAY...South typhoon force wind to 115 kt with gusts to 130 kt. Seas 31 to 35 ft. Widespread showers and scattered thunderstorms. .TONIGHT...Southwest tropical storm force wind to 55 kt with gusts to 85 kt. Seas 25 to 29 ft. Isolated thunderstorms. Widespread showers. .THURSDAY...Southwest tropical storm force wind to 45 kt with gusts to 60 kt. Seas 20 to 24 ft. Scattered showers with isolated thunderstorms. .THURSDAY NIGHT...Southwest tropical storm force wind to 35 kt with gusts to 45 kt. Seas 16 to 19 ft. Scattered showers. .FRIDAY...Southwest wind 15 to 25 kt. Seas 12 to 15 ft. Scattered showers. .SATURDAY...Southwest wind 10 to 15 kt. Seas 7 to 9 ft. Wave Detail: Northwest 9 ft at 9 seconds and southwest 3 ft at 5 seconds. .SUNDAY...Southwest wind 5 to 10 kt. Seas 6 to 8 ft. Wave Detail: North 7 ft at 11 seconds and southwest 2 ft at 4 seconds. $$