599  
FXPQ50 PGUM 060852  
AFDGUM  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TIYAN GU  
652 PM CHST SAT SEP 6 2025  
   
MARIANAS SYNOPSIS  
 
LIGHT TO GENTLE NORTHEASTERLIES PREVAIL ACROSS THE REGION. SATELLITE  
IMAGERY AND DOPPLER RADAR INDICATE SLOW-MOVING SHOWERS FORMING IN  
CNMI WATERS. THE BUOYS SHOW SEAS ARE AROUND 3 FEET.  
 
 
   
DISCUSSION  
 
A PASSING BROAD SURFACE TROUGH INTERACTING WITH A TROPICAL UPPER  
TROPOSPHERIC TROUGH (TUTT) CELL ALOFT, IS LIKELY TO PRODUCE PATCHY  
SHOWERS AND SOME THUNDERSTORMS OVERNIGHT ACROSS THE REGION. AFTER, A  
PERIOD OF ISOLATED TO LOW-END SCATTERED SHOWERS BROUGHT BY MODERATE  
TRADES IS EXPECTED TO LAST FOR MUCH OF NEXT WEEK.  
 
 
   
MARINE/SURF  
 
COMBINED SEAS OF AROUND 4 FEET, WILL BRIEFLY DROP A FOOT EARLY NEXT  
WEEK, BEFORE GOING UP A FEW FEET ONCE TRADE AND NORTHERLY SWELLS,  
ALONG WITH LOCALIZED WIND WAVES, STRENGTHEN AROUND MIDWEEK. A LOW RISK  
OF RIP CURRENTS IS EXPECTED ALONG ALL REEFS OF THE MARIANAS FOR AT  
LEAST THE NEXT SEVERAL DAYS. BY MIDWEEK, TRADE AND NORTHERLY SWELLS  
ARE EXPECTED TO STRENGTHEN SLIGHTLY, ALLOWING SURF TO INCREASE AND  
POTENTIALLY INTRODUCING A MODERATE RISK OF RIP CURRENTS TO NORTH AND  
EAST FACING REEFS AS EARLY AS TUESDAY NIGHT.  
 
 
   
EASTERN MICRONESIA  
 
THE DRY TRADE-WIND PATTERN CONTINUES OVER EASTERN MICRONESIA THIS  
EVENING, WITH ONLY SPOTTY SHOWERS SEEN ACROSS THE REGION. THIS DRY  
PATTERN LOOKS TO CONTINUE THROUGH THE REMAINDER OF THE WEEKEND. IT  
STILL LOOKS LIKELY THAT THE INTER-TROPICAL CONVERGENCE ZONE (ITCZ)  
WILL MAKE A COMEBACK, THOUGH IT WAS PUSHED BACK A LITTLE LATER THAN  
PREVIOUSLY EXPECTED. REGARDLESS, ONCE THE ITCZ REFORMS, THE REGION IS  
IN FOR ANOTHER ROUND OF WET CONDITIONS. CONVECTION WILL BEGIN TO  
INCREASE MONDAY WITH THE RISK OF THUNDERSTORMS INCREASING LATER IN  
THE EVENING. THE ITCZ LOOKS TO PEAK AROUND THE MIDDLE OF NEXT WEEK.  
MAINTAINED POPS AT AROUND 50% FOR NOW, THOUGH THIS COULD CHANGE AS  
THE LOCATION AND STRENGTH OF THE ITCZ BECOMES MORE CLEAR. THIS WET  
PATTERN WILL THEN BEGIN TO SUBSIDE AROUND THE END OF NEXT WEEK.  
 
LITTLE CHANGE IN THE MARINE FORECAST. COMBINED SEAS OF 3 TO 4 FEET  
ARE EXPECTED TO CONTINUE THROUGH THE MIDDLE OF NEXT WEEK, THEN BUILD  
SLIGHTLY AROUND THE END OF THE WEEK. LIGHT TO GENTLE TRADE WINDS ARE  
EXPECTED THROUGH THE COMING WEEK.  
 
 
   
WESTERN MICRONESIA  
 
A BROAD SURFACE TROUGH IS MOVING AWAY FROM CHUUK AND INTO EASTERN  
YAP STATE THIS EVENING. THIS FEATURE IS EXPECTED TO CONTINUE  
PROPAGATING WESTWARD, INCREASING SHOWERS FOR YAP AND PALAU AROUND  
SUNDAY NIGHT THROUGH MONDAY NIGHT. MEANWHILE, SHOWERS ARE EXPECTED TO  
TREND DOWN NEAR WENO OVERNIGHT AND SUNDAY. THEN THE ITCZ BEGINS TO  
REBUILD IN EASTERN MICRONESIA AND MUCH OF CHUUK STATE NEXT WEEK,  
TRENDING TOWARDS WETTER WEATHER BY MONDAY NIGHT. AN ITCZ FRAGMENT  
LOOKS TO BRING ANOTHER UPTICK IN SHOWERS FOR YAP AND PALAU AS WELL,  
AROUND WEDNESDAY AND THURSDAY.  
 
ALTIMETRY DATA SHOWS BENIGN SEAS OF 2 TO 3 FEET NEAR YAP AND PALAU  
AND 3 TO 4 FEET NEAR CHUUK. COMBINED SEAS ARE EXPECTED TO INCREASE TO  
3 TO 5 FEET AROUND THE MIDDLE OF NEXT WEEK WHEN A PULSE OF NORTHERLY  
SWELL MOVES THROUGH THE REGION.  
 
 
   
GUM WATCHES/WARNINGS/ADVISORIES  
 
GU...NONE.  
MP...NONE.  
MARIANAS WATERS...NONE.  
 
 
 
 
MARIANAS: MONTVILA  
EAST MICRONESIA: KLEESCHULTE  
WEST MICRONESIA: CRUZ  
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