692  
FXPQ50 PGUM 270806  
AFDGUM  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TIYAN GU  
606 PM CHST THU AUG 27 2026  
   
MARIANAS SYNOPSIS
 
 
SATELLITE AND RADAR SHOW MOSTLY CLOUDY SKIES WITH SCATTERED SHOWERS  
FOR TONIGHT, NONE LOOK ALL THAT HEAVY AT THIS TIME THOUGH. THERE ARE  
NO BUOYS LEFT IN THE MARIANAS CURRENTLY, HOWEVER WAVE MODELS SHOW  
ABOUT 4 TO 5 FOOT SEAS. TWO SEPARATE ALTIMETRY PASSES ARE IN GOOD  
GENERAL AGREEMENT WITH THAT, ONE WEST OF THE MARIANAS, AND ONE EAST.  
 

 
   
DISCUSSION
 
 
LOOKS LIKE SCATTERED SHOWERS WILL CONTINUE MOST OF THIS WEEK WITH THE  
MONSOON TROUGH STAYING NEAR OR JUST NORTH OF THE AREA. STANDARD WET  
SEASON FARE (ESPECIALLY FOR DURING AN EL NINO EVENT) WITH WESTERLY  
WINDS AND SCATTERED SHOWERS. LOOK FOR THIS TO CONTINUE FOR THE NEXT  
WEEK, WITH LITTLE UPS AND DOWNS. THE RAIN LOOKS A BIT LESS HEAVY FOR  
TONIGHT AND FRIDAY THOUGH, ESPECIALLY ON RADAR AND SATELLITE, SO WENT  
AHEAD AND TOOK OUT THE LOCALLY HEAVY WORDING.  
 

 
   
MARINE
 
 
THE WAVE MODELS HAVE BACKED OFF ON THE PREVIOUSLY EXPECTED WAVE  
HEIGHT INCREASE, NOW IT'S LARGELY FLAT THE ENTIRE PERIOD. WITHOUT  
SOMETHING BIG TO STIR THE POT, WHICH CERTAINLY ISN'T HAPPENING THE  
NEXT FEW DAYS, THIS SEEMS LIKELY TO CONTINUE, AND THIS IS NOW WHAT'S  
IN THE FORECAST.  
 

 
   
TROPICAL SYSTEMS
 
 
WE HAVE TWO TROPICAL CYCLONES NOW THAT ARE RATHER CLOSE TO EACH  
OTHER, SO CLOSE IN FACT THAT THEY HAVE STARTED TO ORBIT EACH OTHER IN  
WHAT IS CALLED A FUJIWARA AFTER THE ONE WHO FIRST DESCRIBED IT. THE  
ONLY ISLAND THEY'RE CLOSE ENOUGH TO THREATEN IS WAKE ISLAND, AND EVEN  
THEN THE THREAT IS MINIMAL SINCE THEY'RE WEAK TROPICAL STORMS. WITH  
TIME, THEY'RE BOTH EXPECTED TO LIFT NORTHWARD AND LEAVE MICRONESIA  
THROUGH THE 25N EXIT.  
 
FOR MORE INFORMATION ON TROPICAL STORM ETAU (21W), PLEASE REFER TO  
THE TROPICAL CYCLONE WARNING ISSUED BY THE JOINT TYPHOON WARNING  
CENTER UNDER WMO HEADER WTPN32 PGTW, OR THE TROPICAL CYCLONE PUBLIC  
ADVISORY, ISSUED BY THE NATIONAL WEATHER SERVICE, UNDER WMO HEADER  
WTPQ32 PGUM.  
 
FOR MORE INFORMATION ON TROPICAL STORM 20W, PLEASE REFER TO THE  
TROPICAL CYCLONE WARNING ISSUED BY THE JOINT TYPHOON WARNING CENTER  
UNDER WMO HEADER WTPN33 PGTW, OR THE TROPICAL CYCLONE PUBLIC  
ADVISORY, ISSUED BY THE NATIONAL WEATHER SERVICE, UNDER WMO HEADER  
WTPQ33 PGUM.  
 

 
   
EASTERN MICRONESIA
 
 
MOSTLY DRY CONDITIONS ARE EXPECTED TO PERSIST ACROSS THE FORECAST  
SITES THROUGH FRIDAY WITH SHOWER CHANCES TOPPING OUT AROUND 30  
PERCENT. GENTLE TO MODERATE WEST TO SOUTHWEST WINDS WILL CONTINUE AT  
POHNPEI FOR THE NEXT SEVERAL DAYS WHILE LIGHT TO GENTLE WINDS PERSIST  
AT KOSRAE AND MAJURO. THEN, THE MONSOON TROUGH MAY ENTER ANOTHER  
ACTIVE PHASE WITH SHOWER AND THUNDERSTORM CHANCES INCREASING THROUGH  
THE WEEKEND, MAINLY CONCENTRATING OVER POHNPEI. ANOTHER DRY SPELL MAY  
FOLLOW SHORTLY THEREAFTER THROUGH THE MIDDLE OF NEXT WEEK. COMBINED  
SEAS AROUND 4 TO 6 FEET WILL PREVAIL FOR THE REST OF THE WEEK WITH  
SEAS CONSISTING OF A WEST TO SOUTHWEST SWELL AT POHNPEI AND KOSRAE,  
AND A NORTHEAST SWELL AT MAJURO. THE SOUTHERLY SWELLS AT KOSRAE WILL  
CONTINUE TO INDUCE ELEVATED SURF ALONG SOUTH-FACING REEFS, BUT WILL  
STILL REMAIN BELOW HAZARDOUS CRITERIA.  
 

 
   
WESTERN MICRONESIA
 
 
SATELLITE IMAGERY SHOWS SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS  
ACROSS YAP STATE AND ISOLATED SHOWERS ACROSS PALAU AND CHUUK.  
ALTIMETRY SHOWS COMBINED SEAS BETWEEN 4 AND 6 FEET ACROSS THE  
REGION.  
 
THE ACTIVE MONSOON PATTERN THAT BROUGHT HEAVY RAINFALL AND FLASH  
FLOODING TO YAP HAS BEGUN TO SHIFT NORTHWARD, MAINLY IMPACTING THE  
ISLANDS OF ULITHI AND FAIS. THESE SHOWERS AND THUNDERSTORMS ARE  
EXPECTED TO CONTINUE TO SHIFT NORTHWARD OVER THE COMING DAYS WITH  
DRIER CONDITIONS RETURNING TO THE REGION. SOME HEAVY RAINFALL WILL  
REMAIN POSSIBLE TONIGHT, BUT OVERALL THE HEAVY RAINFALL THREAT HAS  
DIMINISHED. DRY CONDITIONS WILL PREVAIL THROUGH THE WEEKEND BEFORE A  
POTENTIAL MONSOON DISTURBANCE MOVES ACROSS YAP STATE EARLY NEXT  
WEEK.  
 
THE MAIN CONCERN FOR PALAU WILL BE ISOLATED SHOWERS TONIGHT ALONG A  
NARROW BAND OF SURFACE CONVERGENCE. A THUNDERSTORM IS ONGOING  
NEAR THE EDGE OF THE COASTAL WATERS, BUT LOWER PWATS ACROSS PALAU  
GENERALLY DO NOT SUPPORT THUNDER IN THE FORECAST CLOSER TO THE  
ISLANDS. PWATS BELOW 1.5 INCHES ARE SEEN SOUTH OF PALAU AND LOOK TO  
MOVE INTO THE COASTAL WATERS LATE TONIGHT OR EARLY TOMORROW. THESE  
DRIER CONDITIONS WILL HELP TO KEEP SHOWER CHANCES AT OR NEAR ZERO.  
THE CURRENT FORECAST CALLS FOR NO SHOWERS THROUGH SUNDAY AS DRIER AIR  
AND SURFACE DIVERGENCE MOVE OVER PALAU. ADDITIONALLY THE DRIER  
CONDITIONS IN COMBINATION WITH 10 TO 15 KT WINDS SHOULD KEEP ISLAND  
EFFECT SHOWERS FROM INITIATING. DROUGHT CONDITIONS COULD WORSEN IF A  
PROLONGED DRY PERIOD ESTABLISHES ITSELF.  
 
CHUUK WILL START THE FORECAST PERIOD QUIET WITH ISOLATED SHOWERS  
EXPECTED TONIGHT AND ON FRIDAY. BY FRIDAY NIGHT, THE ACTIVE MONSOON  
PATTERN LOOKS TO REORIENT ITSELF OVER CHUUK STATE BRINGING SCATTERED  
SHOWERS. THIS WEEKEND, A MONSOON DISTURBANCE LOOKS TO FORM JUST  
NORTH OR OVER CHUUK STATE, BRINGING NUMEROUS AND LIKELY SHOWERS AND  
ISOLATED THUNDERSTORMS TO THE REGION. A SLIGHT DECREASE IN SHOWER  
COVERAGE IS POSSIBLE NEXT WEEK, BUT THE ACTIVE PATTERN LOOKS TO  
CONTINUE. RESIDENTS ACROSS CHUUK STATE SHOULD CONTINUE TO MONITOR  
FORECAST OVER THE COMING DAYS FOR THE POTENTIAL FOR HEAVY RAINFALL  
THAT COULD LEAD TO FLOODING.  
 
COMBINED SEAS ARE BETWEEN 4 AND 6 FEET ACROSS THE REGION. SEAS LOOK  
TO REMAIN BENIGN THROUGH SATURDAY NIGHT. ON SUNDAY, AN INCREASE IN  
THE MONSOON WINDS LOOKS TO OCCUR OVER YAP AND CHUUK, LEADING TO  
HIGHER WINDS WAVES AND A MORE DEVELOPED SWELL. AT THIS TIME,  
HAZARDOUS MARINE CONDITIONS OR COASTAL CONDITIONS APPEAR UNLIKELY.  
HOWEVER, CHOPPY SEAS CAN MAKE INTER-ISLAND TRAVEL DIFFICULT AT  
TIMES, ESPECIALLY DURING HEAVIER SHOWERS NEAR CHUUK THIS WEEKEND.  
 

 
   
GUM WATCHES/WARNINGS/ADVISORIES
 
 
GU...NONE.  
MP...NONE.  
MARIANAS WATERS...NONE.  

 
 

 
 
MARIANAS/TROPICAL: STANKO  
EAST MICRONESIA: MESA  
WEST MICRONESIA: WILLIAMS  
 
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