193  
FXPQ50 PGUM 032036  
AFDGUM  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TIYAN GU  
636 AM CHST TUE NOV 4 2025  
   
MARIANAS UPDATE
 
 
SATELLITE AND RADAR OBSERVATIONS SHOW SCATTERED SHOWERS AND  
ISOLATED THUNDERSTORMS ACROSS THE MARIANAS. ALTIMETRY AND BUOY DATA  
SHOW COMBINED SEAS BETWEEN 5 AND 8 FEET.  
 
THIS FORECAST PACKAGE FEATURES A LARGER UPDATE THROUGH FRIDAY DUE TO  
THE CHANGES FROM INVEST 90W. THE JOINT TYPHOON WARNING CENTER HAS  
ISSUED A TROPICAL CYCLONE FORMATION ALERT FOR INVEST 90W, WHICH  
MEANS DEVELOPMENT IS LIKELY WITHIN THE NEXT 24 HOURS. LATEST MODEL  
GUIDANCE GENERALLY KEEPS INVEST 90W JUST SOUTH OF GUAM'S COASTAL  
WATERS AS IT MAKES ITS CLOSEST APPROACH SOMETIME LATE WEDNESDAY  
EVENING THROUGH THURSDAY AFTERNOON. HOWEVER, IMPACTS ARE EXPECTED TO  
BE FELT WELL AWAY FROM THE CENTER WITH HEAVY RAINFALL AND WINDY  
CONDITIONS EXPECTED TO IMPACT THE MARIANAS. AT THIS TIME, THE  
GREATEST IMPACTS LOOK TO BE ACROSS GUAM AND ROTA, BUT THIS COULD  
CHANGE IF THE SYSTEM IS SLOWER TO DEVELOP AND THE STRONGEST WINDS ARE  
FELT FURTHER AWAY FROM THE CENTER. BEYOND FRIDAY, NO CHANGES WERE  
MADE TO THE FORECAST. SHOWERS AND THUNDERSTORMS LOOK TO REMAIN IN THE  
FORECAST THIS WEEKEND AS CONVERGENCE FROM THE EXITING TROPICAL  
DISTURBANCE AND A TRADE-WIND SURGE WILL SETUP ACROSS THE REGION.  
 
OVERALL, ONLY MINOR CHANGES WERE MADE TO THE MARINE FORECAST. THE  
MAIN CHANGE WAS A SLIGHT INCREASE IN WIND WAVES, WHICH COULD BRING 9  
FOOT SEAS TO THE EASTERN COASTAL WATERS OF GUAM AND ROTA BY  
WEDNESDAY NIGHT. CONDITIONS ALSO LOOK TO BECOME HAZARDOUS TO SMALL  
CRAFT LATE IN THE DAY WEDNESDAY WITH WINDS OF 25 KNOTS EXPECTED.  
THERE IS SOME CONCERN FOR COASTAL INUNDATION DUE TO A COMBINATION OF  
A TRADE-WIND SWELL AND THE LUNAR PHASE. AT THIS TIME, INUNDATION IS  
EXPECTED TO BE BELOW ADVISORY CRITERIA, BUT THIS COULD CHANGE  
SIGNIFICANTLY BASED ON THE TRACK AND STRENGTH OF INVEST 90W. WITH THE  
APPROACH OF INVEST 90W, A HIGH RISK FOR RIP CURRENTS WILL BE  
POSSIBLE ACROSS EAST AND SOUTH FACING REEFS, WITH THE POTENTIAL FOR  
HAZARDOUS SURF ALONG SOUTH FACING REEFS AS WELL.  
 

 
   
TROPICAL SYSTEMS UPDATE
 
 
JTWC'S INVEST 90W IS NOW THE SUBJECT OF A TROPICAL CYCLONE FORMATION  
ALERT (TCFA), MEANING DEVELOPMENT INTO A SIGNIFICANT TROPICAL  
CYCLONE IS EXPECTED WITHIN 24 HOURS. 90W CONTINUES TO CONSOLIDATE  
EARLY THIS MORNING, WITH HEAVY CONVECTION FOCUSED ALONG THE EASTERN  
AND SOUTHERN FLANKS OF THE CIRCULATION, CLOSE TO THE CENTER AND  
EXTENDING SOUTHWEST ACROSS MUCH OF EASTERN AND SOUTHERN YAP STATE.  
THE CENTER IS CURRENTLY LOCATED AT AROUND 9N145E, NEAR FARAULEP AND  
GAFERUT IN YAP STATE. MODEL GUIDANCE INDICATES 90W WILL MOVE  
NORTHWEST OVER THE NEXT DAY OR SO, MAKING A WEST-NORTHWEST TURN NEAR  
OR SOUTH OF THE MARIANAS AROUND WEDNESDAY NIGHT, BRINGING STRONG  
WINDS AND HEAVY SHOWERS AND THUNDERSTORMS, WITH THE MAIN IMPACTS  
EXPECTED FOR GUAM AND ROTA, BUT THIS MAY CHANGE IF THE SYSTEM TRACKS  
FURTHER NORTH CLOSER TO THE MARIANAS.  
 
FOR MORE INFORMATION ON INVEST 90W PLEASE SEE BULLETINS FOR THE  
WESTERN/SOUTHERN PACIFIC OCEAN ISSUED BY THE JOINT TYPHOON WARNING  
CENTER UNDER WMO HEADER WTPN21 PGTW.  
 

 
   
HYDROLOGY
 
 
A FLOOD WATCH WAS ISSUED FOR GUAM AND ROTA BEGINNING 4 AM WEDNESDAY  
MORNING AND CONTINUING THROUGH FRIDAY AFTERNOON. AS SUCH, THE  
PREVIOUS ESF WAS CANCELED AND REPLACED BY THE FLOOD WATCH. CONFIDENCE  
IS HIGHEST FOR THE POTENTIAL OF FLASH FLOODING OVER GUAM DUE TO  
CLOSER PROXIMITY OF INVEST 90W. UNCERTAINTY REGARDING MUDSLIDE RISK  
DURING THE WEEKEND REMAINS HIGH. GUIDANCE CONTINUES TO SHOW PROLONGED  
SURFACE CONVERGENCE SETTING UP OVER THE MARIANAS BY LATE FRIDAY,  
LEADING TO CONTINUED HEAVY RAINFALL. THE CONTINUED RAINFALL INTO THE  
WEEKEND WOULD LIKELY SATURATE SOILS ENOUGH TO INCREASE MUDSLIDE RISK.  
ADDITIONALLY, THE FLOOD WATCH MAY NEED TO BE EXTENDED TO TINIAN AND  
SAIPAN THIS WEEKEND DEPENDING ON THE EXACT LOCATION OF THE  
CONVERGENCE ZONE. RESIDENTS SHOULD CONTINUE TO CLOSELY MONITOR THE  
DEVELOPING SITUATION AS FLOOD WATCHES, ADVISORIES, AND FLASH FLOOD  
WARNINGS COULD BE ISSUED LATER.  
 

 
   
EASTERN MICRONESIA UPDATE
 
 
SATELLITE EARLY THIS MORNING REVEALS A GENERALLY QUIET TRADE WIND  
PATTERN ACROSS MUCH OF EASTERN MICRONESIA, BUT SHOWERS ARE INCREASING  
NEAR AND EAST OF MAJURO ALONG AN AREA OF TRADE-WIND CONVERGENCE AND  
SUBTLE TROUGHING. OVERALL, THERE WAS LITTLE CHANGE TO THE FORECAST.  
SHOWERS WERE INCREASED TO LOW-END SCATTERED (30 PERCENT CHANCE) FOR  
KOSRAE TONIGHT AS A TRADE-WIND TROUGH BUILDS WESTWARD INTO THE AREA.  
A MORE ROBUST TROUGH WILL MAINTAIN SCATTERED SHOWERS FOR MAJURO  
THROUGH MIDWEEK AS IT PROPAGATES WESTWARD THROUGH THE MARSHALL  
ISLANDS. A COASTAL FLOOD ADVISORY IS IN EFFECT FOR MAJURO THIS  
AFTERNOON THROUGH SATURDAY AFTERNOON DUE TO A BUILDING NORTHEAST  
TRADE SWELL COINCIDING WITH HIGH TIDES, WHICH ARE EXPECTED TO BRING  
MINOR COASTAL FLOODING OF 1 TO 2 FEET TO NORTH AND EAST FACING REEFS.  
 

 
   
WESTERN MICRONESIA UPDATE
 
 
HEAVY SHOWERS AND THUNDERSTORMS CONTINUE ACROSS MUCH OF EASTERN YAP  
STATE AND WESTERN CHUUK STATE, FOCUSED NEAR AND SOUTH OF THE CENTER  
OF INVEST 90W, WHICH IS NOW THE SUBJECT OF A TROPICAL CYCLONE  
FORMATION ALERT, MEANING A SIGNIFICANT TROPICAL CYCLONE IS EXPECTED  
TO DEVELOP WITHIN 24 HOURS. THE SPECIAL WEATHER STATEMENT FOR THE  
OUTER ISLANDS OF YAP AND CHUUK STATE WAS UPDATED AND RE-ISSUED  
OVERNIGHT, AS INVEST 90W WAS UPGRADED TO HIGH. INVEST 90W IS  
EMBEDDED WITHIN THE MONSOON TROUGH THAT STRETCHES ACROSS WESTERN  
MICRONESIA, EXTENDING JUST NORTH OF PALAU AND PASSING NEAR YAP, WITH  
SCATTERED TO NUMEROUS SHOWERS AND ISOLATED TO SCATTERED THUNDERSTORMS  
SEEN MAINLY SOUTH OF THE TROUGH AXIS AND WRAPPING INTO 90W. OVERALL,  
THERE WAS LITTLE CHANGE TO THE FORECAST. SHOWERS HAVE BEEN ON A  
STEADY INCREASE NEAR PALAU AND WERE INCREASED SLIGHTLY IN TODAY'S  
FORECAST.  
 

 
   
PREV DISCUSSION
 
/ISSUED 637 PM CHST MON NOV 3 2025/  
 
MARIANAS SYNOPSIS...  
MODERATE TO FRESH EASTERLIES PREVAIL ACROSS THE MARIANAS. SATELLITE  
IMAGERY AND DOPPLER RADAR INDICATE A LINE OF SHOWERS MOVING ACROSS  
GUAM WATERS, FOLLOWED BY A BROAD SURFACE TROUGH MOVING IN FROM  
UPSTREAM, AS IT INTERACTS WITH UPPER-LEVEL FEATURES TO PRODUCE  
LIGHTNING. BUOYS SHOW SEAS ARE BETWEEN 5 AND 8 FEET.  
 
DISCUSSION...  
THE TROPICAL DISTURBANCE THAT IS DEVELOPING IN CENTRAL MICRONESIA AND  
REMAINS TO BE THE PRIMARY CULPRIT FOR INCREASING WEATHER ACROSS THE  
MARIANAS, IS NOW KNOWN AS JTWC'S INVEST 90W. THIS SYSTEM CONTINUES  
TO CONSOLIDATE, AND IS EXPECTED TO BEGIN MOVING TOWARD THE MARIANAS  
BY WEDNESDAY. AS IT APPROACHES, SHOWER AND THUNDER COVERAGE WILL  
INCREASE, WITH THE HEAVIEST SHOWERS AND POTENTIALLY STRONGER WINDS  
EXPECTED TO ARRIVE BY WEDNESDAY NIGHT. EVEN WITH THE CONSISTENT STORM  
MOTION TRENDS, HIGH UNCERTAINTY REMAINS REGARDING WIND IMPACTS, AS  
THE SYSTEM REMAINS LARGELY DISORGANIZED. EVEN SO, MODERATE TO FRESH  
TRADES MAY BECOME FRESH TO STRONG AS EARLY AS TUESDAY NIGHT, WITH A  
CHANCE FOR WINDY CONDITIONS TO DEVELOP COMING INTO THE SECOND HALF OF  
THE WEEK. ONCE CERTAINTY INCREASES, A WIND ADVISORY MAY BE ISSUED  
ACROSS THE MARIANAS, IF CONDITIONS WARRANT. AFTER THE SYSTEM EXITS  
TO THE WEST, FEEDER BANDS ALONG THE LEESIDE OF THE SYSTEM MAY BRING  
AN EXTENDED PERIOD OF RAINFALL FOR THE REST OF THE WEEK, BUT LOOKS  
LIKE MODEL GUIDANCE IS GOING TOO AGGRESSIVE ON SHOWER COVERAGE  
DURATION COMING INTO THE TAIL END OF THE FORECAST CYCLE.  
 
MARINE...  
SEA CONDITIONS HAVE IMPROVED STEADILY ENOUGH TO NO LONGER BE  
HAZARDOUS TO SMALL CRAFT AT THIS TIME. AS SUCH, THE SMALL CRAFT  
ADVISORY WAS CANCELLED FOR TODAY. COMBINED SEAS OF 5 TO 7 FEET ARE  
EXPECTED TO INCREASE SLOWLY OVER THE NEXT SEVERAL DAYS, BEFORE  
PICKING UP SUDDENLY DURING 90W'S PASSAGE, POTENTIALLY PRODUCING SEA  
CONDITIONS HAZARDOUS TO SMALL CRAFT BEFORE THE WEEKEND.  
A MODERATE RISK OF RIP CURRENTS IS EXPECTED ALONG NORTH AND EAST  
FACING REEFS OF THE MARIANAS THROUGH AT LEAST MIDWEEK. AFTER,  
SOUTHEASTERLY TO SOUTHERLY FLOW CAUSED BY 90W MAY INTRODUCE A  
MODERATE RIP CURRENT RISK ALONG SOUTH FACING REEFS, AND A HIGH RIP  
CURRENT RISK ALONG EAST FACING REEFS BY THE WEEKEND.  
 
TROPICAL SYSTEMS...  
A LARGELY DISORGANIZED TROPICAL DISTURBANCE, NOW KNOWN AS JTWC'S  
INVEST 90W, IS CENTERED NEAR 9N147E IN EASTERN YAP STATE, JUST  
NORTHWEST OF SATAWAL. AN OPEN-CELL CONFIGURATION, WITH 15 TO 20 KT  
SUSTAINED MONSOONAL INFLOW, IS EXPECTED TO MOVE INTO A VERY TIGHT  
NEUTRAL ZONE TUCKED BETWEEN TWO MASSIVE WIND SHEAR ZONES THAT CAN  
TAKE APART THE SYSTEM; THIS NEUTRAL ZONE IS SITUATED RIGHT OVER THE  
MARIANAS. THE SHEAR TENDENCY IN THIS POCKET OF HOPE CONTINUES TO  
DECREASE, GIVEN THAT THE SYSTEM CONTINUES TO MEANDER IN ITS GENERAL  
VICINITY WHILE GAINING STEAM PRIOR TO ITS EXIT TO THE NORTH. AT THIS  
TIME, THE INVEST AREA IS DESIGNATED AS A LOW, INDICATING THAT  
DEVELOPMENT INTO A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24  
HOURS IS NOT LIKELY. MODEL TRENDS CONTINUE TO SHOW A SIGNAL FOR  
INTENSIFICATION COMING INTO THE SECOND HALF OF THE WEEK, WHEN THE  
EASTERN PERIPHERY RAIN BANDS WILL MOVE IN ACROSS THE MARIANAS DURING  
PASSAGE. DUE TO THE LACKLUSTER NATURE OF THIS SYSTEM, HIGH  
UNCERTAINTY REMAINS IN THE STORM MOTION AT THIS TIME.  
 
FOR MORE INFORMATION ON INVEST 90W PLEASE SEE THE SIGNIFICANT  
TROPICAL WEATHER ADVISORY BULLETIN FOR THE WESTERN/SOUTHERN PACIFIC  
OCEAN ISSUED BY THE JOINT TYPHOON WARNING CENTER UNDER WMO HEADER  
ABPW10 PGTW.  
 
HYDROLOGY...  
MODERATE UNCERTAINTY REMAINS REGARDING POTENTIAL RAINFALL IMPACTS,  
BUT EARLY ESTIMATES INDICATE THIS SYSTEM TO BRING LOCALLY HEAVY  
RAINFALL OF 5 TO 8 INCHES ACROSS THE MARIANAS BY THE WEEKEND.  
WITH SUCH RAINFALL, FLASH FLOODING REMAINS A POSSIBILITY WEDNESDAY  
THROUGH SATURDAY. UNCERTAINTY REGARDING MUDSLIDE RISK DURING THE  
WEEKEND REMAINS HIGH. IF FEEDER BANDS FORM, SHOWERS ARE LIKELY TO  
PERSIST INTO THE WEEKEND, WHICH WOULD BECOME MORE LIKELY TO SATURATE  
THE SOILS ENOUGH TO INCREASE MUDSLIDE RISK. RESIDENTS NEED TO CLOSELY  
MONITOR THIS DEVELOPING SITUATION AS FLOOD WATCHES, ADVISORIES AND  
FLASH FLOOD WARNINGS COULD BE ISSUED LATER.  
 
EASTERN MICRONESIA...  
A DRY TRADE-WIND PATTERN CONTINUES ACROSS EASTERN MICRONESIA WITH  
ONLY PARTLY CLOUDY SKIES, SPOTTY SHOWERS SEEN ACROSS THE REGION.  
LIGHT TO OCCASIONALLY GENTLE TRADE WINDS ARE IN PLACE AT POHNPEI AND  
KOSRAE, WITH GENTLE TO MODERATE WINDS AT MAJURO.COMBINED SEAS ARE 3  
TO 5 FEET ACROSS THE REGION.  
 
MAJURO LOOKS TO BE THE FIRST TO SEE INCREASING CONVECTION, WITH LOW-  
END SCATTERED SHOWERS EXPECTED TUESDAY AS A WEAK TROUGH MOVES  
THROUGH THE AREA. BEHIND THIS TROUGH, A SERIES OF TRADE-WIND TROUGHS  
ARE EXPECTED TO MOVE THROUGH THE MARSHALLS, MAINTAINING INCREASED  
CONVECTION THROUGH THURSDAY. A DRIER PERIOD LOOKS LIKELY FOR FRIDAY  
BEFORE AN INTER-TROPICAL CONVERGENCE ZONE (ITCZ) MOVES IN FROM EAST  
OF THE DATE LINE. THIS SHOULD MAKE FOR A WET WEEKEND AT MAJURO.  
 
FOR KOSRAE, THE DRY PATTERN LOOKS TO CONTINUE A WHILE LONGER, WITH  
ONLY ISOLATED SHOWERS EXPECTED THERE THROUGH WEDNESDAY NIGHT. BY  
THURSDAY, THE TRADE-WIND TROUGHS MOVING THROUGH MAJURO SHOULD DROP  
FAR ENOUGH SOUTH TO BRING INCREASED CONVECTION TO KOSRAE. THESE  
TROUGHS ARE EXPECTED TO KEEP THE ISLAND IN A WETTER PATTERN AT LEAST  
INTO THE WEEKEND.  
 
FOR POHNPEI, THE TROUGHS WILL HOLD OFF A BIT LONGER, WITH THE ISLAND  
MAINTAINING A DRY TRADE-WIND PATTERN THROUGH THURSDAY. BY FRIDAY,  
CONVECTION SHOULD INCREASE AS THE FIRST OF THE TROUGHS MAKES ITS WAY  
THROUGH. A WETTER PATTERN IS THEN EXPECTED TO REMAIN AT POHNPEI  
THROUGH THE WEEKEND.  
 
COMBINED SEAS OF 4 TO 6 FEET ARE SEEN AT MAJURO, WITH SEAS BUILDING  
FAIRLY QUICKLY TO BETWEEN 6 AND 8 FEET BY WEDNESDAY. THIS IS DUE TO  
A TRADE-WIND SURGE PRODUCING INCREASED TRADE SWELL OVER THE REGION.  
SEAS ARE EXPECTED TO PEAK AT MAJURO WEDNESDAY NIGHT, BUT REMAIN  
ELEVATED INTO THE WEEKEND. DUE TO HIGHER TIDES OVER THE NEXT FEW  
DAYS, THIS BUILDING SWELL WILL BRING MINOR COASTAL INUNDATION TO  
MAJURO AND OTHER ISLANDS AND ATOLLS IN THE MARSHALLS, WITH 1 TO 2  
FEET OF INUNDATION EXPECTED TUESDAY INTO THE WEEKEND. A COASTAL  
FLOOD ADVISORY HAS BEEN ISSUED WITH INUNDATION STARTING TUESDAY  
AFTERNOON. WINDS WILL BE GENTLE TO MODERATE INTO THE WEEKEND.  
 
FOR POHNPEI, SEAS OF 3 TO 4 FEET WILL SLOWLY BUILD DUE TO THE TRADE-  
WIND SURGE, REACHING AROUND 6 FEET THURSDAY INTO THE WEEKEND. KOSRAE  
WILL SEE COMBINED SEAS OF 3 TO 4 FEET THROUGH WEDNESDAY NIGHT, WHEN  
SEAS BEGIN TO SLOWLY BUILD, REACHING 5 TO 6 FEET OVER THE WEEKEND.  
THIS NORTHEAST SWELL COULD PRODUCE HAZARDOUS SURF CONDITIONS ALONG  
EAST FACING REEFS OVER THE WEEKEND. LIGHT TO GENTLE WINDS AT POHNPEI  
AND KOSRAE WILL BECOME GENTLE TO MODERATE WEDNESDAY INTO THURSDAY.  
 
WESTERN MICRONESIA...  
THE HEAVIEST WEATHER ACROSS THE REGION IS CURRENTLY OVER EASTERN YAP  
AND WESTERN CHUUK STATES, WITHIN THE MONSOON TROUGH AND AROUND THE  
EMBEDDED CIRCULATION BEING MONITORED BY JTWC AS INVEST 90W, LOCATED  
NEAR 9N147E. SATELLITE IMAGERY SHOWERS NUMEROUS LOCALLY HEAVY  
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS THE OUTER ISLANDS WITH  
SCATTEROMETER WIND DATA SHOWING A WESTERLY WIND BURST AROUND 20 TO 30  
KT THIS MORNING SOUTH OF INVEST 90W. THESE SHOWERS AND WINDS ARE  
CREATING HAZARDOUS CONDITIONS THAT WILL MAKE INTER-ISLAND TRAVEL IN  
EASTERN YAP STATE AND WESTERN CHUUK STATE DIFFICULT AND AT TIMES  
DANGEROUS. MODEL GUIDANCE SHOWS THAT INVEST 90W WILL LIKELY  
CONSOLIDATE SLOWLY, WITH LITTLE LIKELIHOOD OF DEVELOPING INTO A  
SIGNIFICANT TROPICAL CYCLONE OVER THE NEXT 24 HOURS, THOUGH HEAVY  
CONVECTION WILL CONTINUE TO BUILD OVER THE EASTERN ISLANDS OF YAP  
STATE AND INTO WESTERN CHUUK STATE. INVEST 90W IS EXPECTED TO SLOWLY  
MOVE NORTHWEST, DRAGGING THE MONSOON TROUGH NORTH AND WEST, PULLING  
THE STRONG MONSOON WINDS AND HEAVY SHOWERS AWAY FROM CHUUK STATE AND  
FURTHER WEST ACROSS YAP STATE.  
 
CHUUK LAGOON CURRENTLY SITES ON THE EASTERN EDGE OF THE MONSOON  
TROUGH SO WINDS ARE MORE SOUTHERLY AND WEAKER, AROUND 10 TO 15 KT,  
WITH SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THIS EVENING. OVER  
THE PAST COUPLE OF HOURS SATELLITE IMAGERY SHOWS COOLING CLOUD TOPS  
IN THE EASTER WATERS OF CHUUK WHICH SUGGEST CONVECTION IS INCREASE,  
SO EXPECT SHOWERS TO BECOME NUMEROUS OVERNIGHT WITH SOME OCCASIONAL  
GUSTS TO 25 KT POSSIBLE IN HEAVIER SHOWERS. AS INVEST 90W AND THE  
MONSOON TROUGH MOVE NORTH AND WEST, WINDS WILL BECOME MORE SOUTHEAST  
AT CHUUK AND THE RISK FOR HEAVY SHOWERS AND STRONG WINDS WILL SHIFT  
WESTWARD OVER THE NEXT FEW DAYS, THOUGH CONVERGENT FLOW INTO THE  
MONSOON TROUGH AND 90W WILL CONTINUE TO SUPPORT A WET PATTERN ACROSS  
CHUUK. PALAU AND YAP PROPER ARE CURRENTLY EXPERIENCING MOSTLY CLOUD  
SKIES BUT SHOWERS CURRENTLY ISOLATED WITH DIFFUSE FLOW OVER BOTH  
LOCATIONS AS PALAU AND YAP ARE CURRENTLY BETWEEN TYPHOON KALMAEGI,  
LOCATED WEST OF 130E AND NEAR THE PHILIPPINES, AND INVEST 90W IN  
EASTERN YAP STATE. AS KALMAEGI CONTINUES TO MOVE AWAY TO THE WEST,  
MODELS SHOW CONVERGENCE INCREASE OVER THE AREA WHICH WILL SUPPORT  
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS LATER TONIGHT AND OVER  
THE NEXT COUPLE OF DAYS. MODELS SUPPORT INVEST 90W MOVING IN WEST-  
NORTHWEST TO NORTH-NORTHWEST DIRECTION WITH TRENDS LARGELY  
SUGGESTING 90W PASSING BETWEEN YAP AND GUAM WEDNESDAY OR THURSDAY,  
THOUGH THERE IS STILL A LARGE DEGREE ON UNCERTAINTY IN MOTION AND  
SPEED OF DEVELOPMENT TO TO 90W'S CURRENT DISORGANIZED STATE. OVERALL,  
THIS GENERAL MOTION WILL SHIFT STRONGER MONSOONAL WINDS AND THE  
POTENTIAL FOR HEAVY SHOWERS TOWARDS PALAU AND YAP, ESPECIALLY DURING  
THE THURSDAY TO SATURDAY TIME FRAME, WITH MODEL GUIDANCE SUPPORTING  
WINDS AROUND 15 TO 20 KT ACROSS PALAU AND POTENTIALLY UP TO 25 KT AT  
YAP.  
 
ALTIMETRY DATA SHOWS SEAS ARE AROUND 5 TO 7 FEET ACROSS THE REGION,  
BUT ARE LIKELY HIGHER AROUND INVEST 90W WHERE CONDITIONS ARE LIKELY  
NEARING OR MEETING HAZARDOUS CONDITIONS OF 22KT AND SEAS OF 10 FEET  
FOR SMALL CRAFT IN EASTERN YAP STATE. THE PRIMARY SWELL CONTINUES TO  
BE THE NORTHEAST SWELL, DRIVEN A TRADE-WIND SURGE IN THE CENTRAL  
PACIFIC, WITH A SECONDARY WESTERLY SWELL GENERATED BY THE MONSOONAL  
FLOW OF THE MONSOON TROUGH THAT IS ALSO BEING ENHANCED BY INVEST 90W,  
AND BY TYPHOON KALMAEGI NEAR THE PHILIPPINES. SEA AND WINDS ARE NOT  
EXPECTED TO CHANGE MUCH AROUND CHUUK THE NEXT FEW DAYS AS THE  
STRONGEST WINDS AND SEAS WILL LIKELY SLOWLY SHIFT WESTWARD FOLLOWING  
THE MONSOON TROUGH AND INVEST 90W. WINDS OF 22KT AND SEAS OF 10 FEET  
ARE POSSIBLE AROUND PALAU AND YAP DURING THE THURSDAY TO SATURDAY  
TIME PERIOD BUT THIS WILL DEPEND ON HOW INVEST 90W DEVELOPS AND MOVES  
OVER THE NEXT FEW DAYS, BUT DEVELOPMENT OVER THE NEXT 24 HOURS INTO  
A SIGNIFICANT TROPICAL CYCLONE IS UNLIKELY. SURF WILL BE ELEVATED  
ALONG WEST, NORTH, AND EAST FACING REEFS ACROSS THE REGION BUT NOT  
EXPECTED TO EXCEED HAZARDOUS LEVELS OF 9 FEET ALONG WEST AND NORTH  
REEFS AND 12 FEET ALONG EAST FACING REEFS THROUGH THE NEXT FEW DAYS.  
HOWEVER, MODELS SHOW THE NORTHEAST SWELL BUILDING NEAR THE END OF THE  
WEEK, WITH A POTENTIAL NORTH TO NORTHWEST SWELL DEVELOPING FROM  
INVEST 90W IF IT STARTS TO ORGANIZE. SURF CONDITIONS COULD BECOME  
HAZARDOUS ALONG SOME REEFS LATE THIS WEEK OR THIS WEEKEND.  
 

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

 
 

 
 
MARIANAS/HYDROLOGY UPDATE: WILLIAMS  
EAST AND WEST MICRONESIA/TROPICAL SYSTEMS UPDATE: DECOU  
MARIANAS/TROPICAL: MONTVILA  
EAST MICRONESIA: KLEESCHULTE  
WEST MICRONESIA: SCHANK  
 
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