FZMY50 PGUM 220613 CWFGUM Coastal Waters Forecast for the Mariana Islands National Weather Service Tiyan GU 413 PM ChST Sat Aug 22 2026 Marianas Waters out to 40 nautical miles PMZ150-222045- 413 PM ChST Sat Aug 22 2026 .Synopsis for Marianas Waters... As Typhoon Saudel passes through the far northern portions of the CNMI near Pagan and Agrihan, another developing tropical disturbance known as Invest 97W, is located northwest of Yap. This will help maintain moderate to fresh southwest winds. Seas of 7 to 9 feet across the coastal waters of Guam and Rota, and 8 to 10 feet for Tinian and Saipan, will continue through Sunday. Then, as Saudel moves further away from the region, 7 to 9 foot seas will affect all of the western coastal waters. However, some forecast guidance suggests the advisory may need to be extended in time, while also expanding south. Stay tuned! $$ PMZ151-152-222045- Guam Coastal Waters-Rota Coastal Waters- 413 PM ChST Sat Aug 22 2026 .TONIGHT...Southwest wind 10 to 20 kt. Seas 7 to 9 ft. Wave Detail: Northwest 7 ft at 9 seconds, west 4 ft at 9 seconds, southwest 3 ft at 5 seconds and southeast 3 ft at 8 seconds. Scattered heavy showers with isolated thunderstorms. .SUNDAY...Southwest wind 15 to 20 kt. Seas 8 to 10 ft. Wave Detail: Northwest 7 ft at 8 seconds, southwest 4 ft at 6 seconds, east 4 ft at 11 seconds and southeast 3 ft at 8 seconds. Scattered heavy showers with isolated thunderstorms. .SUNDAY NIGHT...Southwest wind 10 to 15 kt. Seas 7 to 9 ft. Wave Detail: Northwest 7 ft at 9 seconds, east 4 ft at 11 seconds, southwest 3 ft at 4 seconds and southeast 3 ft at 8 seconds. Scattered heavy showers with isolated thunderstorms. .MONDAY...Southwest wind 10 to 15 kt. Seas 6 to 8 ft. Wave Detail: Northwest 7 ft at 9 seconds, east 5 ft at 13 seconds, southwest 3 ft at 5 seconds and southeast 3 ft at 8 seconds. Scattered heavy showers with isolated thunderstorms. .MONDAY NIGHT...Southwest wind 10 to 15 kt. Seas 6 to 8 ft. Wave Detail: Northwest 6 ft at 9 seconds, east 5 ft at 12 seconds, southwest 2 ft at 4 seconds and southeast 2 ft at 8 seconds. Scattered heavy showers with isolated thunderstorms. .TUESDAY...Southwest wind 5 to 10 kt. Seas 6 to 8 ft. Wave Detail: Southwest 6 ft at 8 seconds, northwest 4 ft at 11 seconds and southwest 2 ft at 4 seconds. A chance of heavy showers with a slight chance of thunderstorms. .WEDNESDAY...Southwest wind 10 to 20 kt. Seas 4 to 6 ft. Wave Detail: Northwest 6 ft at 11 seconds, west 5 ft at 8 seconds and southwest 3 ft at 4 seconds. A chance of showers with a slight chance of thunderstorms. .THURSDAY...Southwest wind 15 to 20 kt. Seas 5 to 7 ft. Wave Detail: Northwest 7 ft at 11 seconds and southwest 4 ft at 5 seconds. Showers likely with a slight chance of thunderstorms. $$ PMZ153-154-222045- Tinian Coastal Waters-Saipan Coastal Waters- 413 PM ChST Sat Aug 22 2026 ...SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH SUNDAY AFTERNOON... .TONIGHT...Southwest wind 10 to 15 kt. Seas 8 to 10 ft. Wave Detail: Northwest 8 ft at 9 seconds, southwest 4 ft at 9 seconds, south 3 ft at 5 seconds and southeast 4 ft at 8 seconds. .SUNDAY...Southwest wind 10 to 20 kt. Seas 7 to 9 ft. Wave Detail: Northwest 7 ft at 8 seconds, west 4 ft at 10 seconds, southwest 3 ft at 5 seconds and southeast 3 ft at 8 seconds. Isolated thunderstorms. .SUNDAY NIGHT...Southwest wind 10 kt. Seas 7 to 9 ft. Wave Detail: Northwest 7 ft at 8 seconds, southwest 4 ft at 10 seconds, east 3 ft at 8 seconds and southwest 2 ft at 4 seconds. Scattered heavy showers with isolated thunderstorms. .MONDAY...South wind 5 to 10 kt. Seas 6 to 8 ft. Wave Detail: Northwest 7 ft at 9 seconds, southwest 4 ft at 11 seconds, southeast 3 ft at 8 seconds and east 2 ft at 4 seconds. Scattered heavy showers with isolated thunderstorms. .MONDAY NIGHT...Southwest wind 5 to 10 kt. Seas 6 to 8 ft. Wave Detail: Northwest 6 ft at 9 seconds, southwest 4 ft at 11 seconds and southeast 2 ft at 8 seconds. Scattered heavy showers with isolated thunderstorms. .TUESDAY...Southeast wind 5 kt. Seas 5 to 7 ft. Wave Detail: Southwest 6 ft at 8 seconds and northwest 4 ft at 11 seconds. A chance of heavy showers with a slight chance of thunderstorms. .WEDNESDAY...Southeast wind 5 to 10 kt. Seas 4 to 6 ft. Wave Detail: Southwest 5 ft at 8 seconds, west 4 ft at 10 seconds and south 2 ft at 4 seconds. A chance of showers with a slight chance of thunderstorms. .THURSDAY...Southwest wind 10 to 15 kt. Seas 5 to 7 ft. Wave Detail: Northeast 7 ft at 10 seconds and southwest 3 ft at 5 seconds. A chance of showers with a slight chance of thunderstorms. $$