


Coastal Waters Forecast
Issued by NWS Tiyan, Guam
Issued by NWS Tiyan, Guam
478 FZMY50 PGUM 200607 CWFGUM Coastal Waters Forecast for the Mariana Islands National Weather Service Tiyan GU 407 PM ChST Sun Apr 20 2025 Marianas Waters out to 40 nautical miles PMZ150-202145- 407 PM ChST Sun Apr 20 2025 .Synopsis for Marianas Waters...Seas are around 3 to 5 feet this evening according the latest altimetry and buoy data. Seas are expected to drop slightly to 3 to 4 feet by Wednesday as the trade swell subsides slightly. A weak trough is slowly approaching from the east and will move through the waters Monday, producing scattered showers, and then exit the waters by Tuesday. Gentle trade winds are expected to becoming gentle to moderate Wednesday. $$ PMZ151>154-202145- MARIANAS COASTAL WATERS- 407 PM ChST Sun Apr 20 2025 .TONIGHT...East wind 10 kt. Seas 3 to 5 ft. Wave Detail: East 4 ft at 8 seconds, east 2 ft at 4 seconds and northeast 2 ft at 10 seconds. .MONDAY...East wind 10 kt. Seas 3 to 5 ft. Wave Detail: East 4 ft at 8 seconds, east 2 ft at 4 seconds and northeast 2 ft at 10 seconds. Scattered showers. .MONDAY NIGHT...East wind 10 kt. Seas 3 to 5 ft. Wave Detail: East 3 ft at 8 seconds, east 2 ft at 4 seconds and north 2 ft at 9 seconds. Scattered showers Guam and Rota waters. .TUESDAY...East wind 10 kt. Seas 3 to 5 ft. Wave Detail: East 4 ft at 8 seconds and east 2 ft at 4 seconds. .TUESDAY NIGHT...East wind 10 kt. Seas around 4 ft. Wave Detail: East 3 ft at 8 seconds and east 2 ft at 4 seconds. .WEDNESDAY THROUGH FRIDAY...East wind 10 to 15 kt. Seas 3 to 4 ft. Wave Detail: East 3 ft at 8 seconds and east 2 ft at 4 seconds. $$