FZMY50 PGUM 261750

CWFGUM



Coastal Waters Forecast for the Mariana Islands

National Weather Service Tiyan GU

Issued by National Weather Service Honolulu HI

350 AM ChST Fri Jun 27 2025



Marianas Waters out to 40 nautical miles



PMZ150-270915-

350 AM ChST Fri Jun 27 2025



.Synopsis for Marianas Waters...A gentler south to southeast flow

will prevail across the Marianas through Saturday as Invest 97W, 

centered west of the Marianas, shifts further away. Combined seas 

of 4 to 6 feet for Guam and Rota, and 5 to 7 feet for Tinian and 

Saipan, look to build late weekend into early next week as a 

monsoon swell begins to build into the region. This looks to be in

response to another possible disturbance developing east of the 

Marianas, leading to a moderate to fresh monsoon flow.



$$



PMZ151-152-270915-

Guam Coastal Waters-Rota Coastal Waters-

350 AM ChST Fri Jun 27 2025



.TODAY...Southeast wind 5 to 10 kt. Seas 3 to 6 ft. Wave Detail:

East 4 ft at 8 seconds and southwest 2 ft at 4 seconds. Scattered

showers with isolated thunderstorms. 

.TONIGHT...Southeast wind 5 to 10 kt. Seas 4 to 6 ft. Wave

Detail: East 4 ft at 8 seconds and southwest 3 ft at 5 seconds.

Scattered showers with isolated thunderstorms. 

.SATURDAY...South wind 5 to 15 kt. Seas 4 to 6 ft. Wave Detail:

Southwest 5 ft at 6 seconds and east 4 ft at 8 seconds. Numerous

showers with isolated thunderstorms. Locally heavy downpours

possible.

.SUNDAY...Southwest wind 10 to 15 kt. Seas 6 to 7 ft. Wave

Detail: Southwest 5 ft at 7 seconds and east 3 ft at 8 seconds.

Showers likely with a slight chance of thunderstorms. Locally 

heavy downpours possible.

.MONDAY THROUGH TUESDAY...Southwest wind 10 to 20 kt. Seas 5 to 7

ft. Southwest 7 ft at 8 seconds A chance of showers with a slight

chance of thunderstorms.



$$



PMZ153-154-270915-

Tinian Coastal Waters-Saipan Coastal Waters-

350 AM ChST Fri Jun 27 2025



.TODAY...Southeast wind 10 kt. Seas 5 to 7 ft. Wave Detail: East

6 ft at 8 seconds and southeast 2 ft at 4 seconds. Scattered

showers with isolated thunderstorms. 

.TONIGHT...Southeast wind 5 to 10 kt. Seas 5 to 7 ft. Wave

Detail: East 6 ft at 8 seconds and south 2 ft at 4 seconds.

Scattered showers with isolated thunderstorms. 

.SATURDAY...Southeast wind 10 kt. Seas 5 to 7 ft. Wave Detail:

East 6 ft at 8 seconds and south 2 ft at 4 seconds. Scattered 

showers with isolated thunderstorms. Locally heavy downpours

possible.

.SUNDAY...South wind 5 to 10 kt. Seas 5 to 7 ft. Wave Detail:

South 5 ft at 7 seconds and east 3 ft at 8 seconds. A chance of 

showers with a slight chance of thunderstorms. Locally heavy 

downpours possible.

.MONDAY THROUGH TUESDAY...Southwest wind 10 to 20 kt. Seas 6 to 8

ft. Southwest 6 ft at 8 seconds. A chance of showers with a 

slight chance of thunderstorms.



$$

