968  
FPMY50 PGUM 202355  
ZFPGUM  
 
ZONE FORECAST FOR GUAM AND THE NORTHERN MARIANAS  
NATIONAL WEATHER SERVICE TIYAN GU  
955 AM CHST FRI AUG 21 2026  
 
GUZ001-MPZ001-210900-  
GUAM-ROTA-  
955 AM CHST FRI AUG 21 2026  
 
...HIGH RIP CURRENT RISK IN EFFECT FROM 3 PM CHST THIS AFTERNOON  
THROUGH SUNDAY AFTERNOON ALONG EAST FACING REEFS...  
   
REST OF TODAY  
PARTLY CLOUDY. ISOLATED SHOWERS IN THE MORNING,  
THEN SCATTERED, LOCALLY HEAVY ISLAND ENHANCED SHOWERS AND ISOLATED  
THUNDERSTORMS BEGINNING NEAR NOON FOR GUAM. LIGHT AND VARIABLE WINDS.  
HIGHS AROUND 86. CHANCE OF SHOWERS 50 PERCENT.   
TONIGHT  
PARTLY CLOUDY WITH ISOLATED SHOWERS AND THUNDERSTORMS.  
LIGHT AND VARIABLE WINDS BECOMING SOUTHWEST 10 TO 15 MPH AFTER  
MIDNIGHT. LOWS AROUND 77. CHANCE OF SHOWERS 20 PERCENT.    
SATURDAY  
BREEZY. PARTLY SUNNY WITH ISOLATED SHOWERS. SOUTHWEST  
WINDS 15 TO 25 MPH. HIGHS AROUND 87. CHANCE OF SHOWERS 20 PERCENT.    
SATURDAY NIGHT AND SUNDAY  
BREEZY. MOSTLY CLOUDY. SCATTERED  
SHOWERS AND ISOLATED THUNDERSTORMS. LOCALLY HEAVY SHOWERS POSSIBLE.  
SOUTHWEST WINDS 20 TO 25 MPH. LOWS AROUND 77. HIGHS AROUND 86. CHANCE  
OF SHOWERS 50 PERCENT.   
SUNDAY NIGHT AND MONDAY  
MOSTLY CLOUDY. SCATTERED SHOWERS AND  
ISOLATED THUNDERSTORMS. LOCALLY HEAVY SHOWERS POSSIBLE. LOWS IN THE  
UPPER 70S. HIGHS IN THE MID 80S. CHANCE OF SHOWERS 30 PERCENT.    
MONDAY NIGHT THROUGH WEDNESDAY  
MOSTLY CLOUDY WITH A 40 PERCENT  
CHANCE OF SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS. LOWS IN THE  
UPPER 70S. HIGHS IN THE MID 80S.    
WEDNESDAY NIGHT AND THURSDAY  
BREEZY. MOSTLY CLOUDY WITH SHOWERS  
LIKELY AND A SLIGHT CHANCE OF THUNDERSTORMS. LOWS IN THE UPPER 70S.  
HIGHS IN THE MID 80S. CHANCE OF SHOWERS 60 PERCENT.  
 
 
 
MPZ002-003-210900-  
TINIAN-SAIPAN-  
955 AM CHST FRI AUG 21 2026  
   
..TROPICAL STORM WATCH IN EFFECT  
 
...HIGH RIP CURRENT RISK IN EFFECT FROM 3 PM CHST THIS AFTERNOON  
THROUGH SUNDAY AFTERNOON ALONG EAST FACING REEFS...  
   
REST OF TODAY  
MOSTLY CLOUDY SCATTERED SHOWERS AND ISOLATED  
THUNDERSTORMS. LIGHT AND VARIABLE WINDS BECOMING NORTHWEST AROUND 10  
MPH IN THE AFTERNOON. HIGHS AROUND 86. CHANCE OF SHOWERS 50 PERCENT.    
TONIGHT  
TROPICAL STORM CONDITIONS POSSIBLE. MOSTLY CLOUDY WITH  
SCATTERED SHOWERS, BECOMING NUMEROUS AND HEAVY AFTER MIDNIGHT.  
ISOLATED THUNDERSTORMS. LOCALLY HEAVY SHOWERS POSSIBLE. WEST WINDS 10  
TO 15 MPH, INCREASING TO 25 TO 40 MPH AFTER MIDNIGHT. LOWS AROUND  
75. CHANCE OF SHOWERS 60 PERCENT.    
SATURDAY THROUGH SUNDAY  
TROPICAL STORM CONDITIONS POSSIBLE.  
CLOUDY. PERIODS OF RAIN, WIDESPREAD HEAVY SHOWERS AND SCATTERED  
THUNDERSTORMS. SOUTHWEST WINDS 30 TO 40 MPH WITH GUSTS TO 45 MPH NEAR  
HEAVIER SHOWERS. HIGHS NEAR 84. LOWS AROUND 76. CHANCE OF SHOWERS 90  
PERCENT.   
SUNDAY NIGHT THROUGH WEDNESDAY  
CLOUDY WITH A 50 PERCENT CHANCE OF  
SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS. LOWS IN THE MID 70S.  
HIGHS IN THE MID 80S.    
WEDNESDAY NIGHT THROUGH THURSDAY  
MOSTLY CLOUDY WITH A 40 PERCENT  
CHANCE OF SHOWERS. LOWS IN THE UPPER 70S. HIGHS IN THE UPPER 80S.  
 
 
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