874
FXPQ50 PGUM 300849
AFDGUM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
649 PM CHST TUE JUN 30 2026
MARIANAS SYNOPSIS
SATELLITE AND RADAR IMAGERY SHOW ISOLATED SHOWERS AND WEAK ISLAND
EFFECT SHOWERS DISSIPATING. LOW-END SCATTERED SHOWERS ARE EXPECTED
TO RETURN LATE TONIGHT AND DISSIPATE BY MORNING. BUOY AND MODEL DATA
SHOW COMBINED SEAS OF 3 TO 4 FEET.
DISCUSSION
A FAIRLY DRY PERIOD WITH WEAK PERIODS OF SCATTERED AND ISOLATED
SHOWERS ARE EXPECTED TO CONTINUE THROUGH FRIDAY. SCATTERED SHOWERS
ARE CURRENTLY EXPECTED LATE TONIGHT, WEDNESDAY NIGHT, AND THURSDAY
NIGHT. UNSTABLE AIR AHEAD OF CURRENT INVEST 95W, CURRENTLY LOCATED
OVER THE MARSHALL ISLANDS, WILL BRING A SLIGHT CHANCE OF
THUNDERSTORMS FOR THE REST OF THE FORECAST PERIOD STARTING FRIDAY
NIGHT. SHOWER COVERAGE LOOKS TO BECOME MORE SCATTERED ON INDEPENDENCE
DAY AS PRECIPITABLE WATER VALUES INCREASE ACROSS THE MARIANAS AHEAD
OF 95W. SHOWERS WILL BECOME MORE WIDESPREAD SUNDAY AND MONDAY WITH
LOCALLY HEAVY SHOWERS POSSIBLE. FLOODING COULD BE A RISK FOR AREAS
WITH THE HEAVIEST RAINFALL. WINDS ARE EXPECTED TO BUILD GRADUALLY
SOMETIME SATURDAY AND COULD BECOME DAMAGING BY SUNDAY NIGHT DEPENDING
ON THE TRACK AND INTENSITY OF 95W. THIS SITUATION REMAINS UNCERTAIN
AND WILL CONTINUE TO BE MONITORED CLOSELY. REFER TO THE TROPICAL
SYSTEMS SECTION BELOW FOR MORE DETAILS ON INVEST 95W.
MARINE
COMBINED SEAS OF 3 TO 4 FEET AND LIGHT TO GENTLE TRADE WINDS ARE
EXPECTED TONIGHT FOR THE MARIANAS. THE MAIN SWELL IS THE EAST-
NORTHEAST TRADE WIND SWELL. THERE WILL BE A MODERATE RISK OF RIP
CURRENTS ALONG EAST FACING REEFS OF THE MARIANAS. WINDS ARE EXPECTED
TO BE LIGHT TO GENTLE THROUGH THE WEEK BEFORE STARTING TO INCREASE
GRADUALLY SOMETIME SATURDAY AHEAD OF INVEST 95W. SCATTERED SHOWERS
ARE EXPECTED LATE TONIGHT, LATE WEDNESDAY NIGHT, AND THURSDAY. BY
FRIDAY, A SLIGHT CHANCE OF THUNDERSTORMS WILL BE POSSIBLE THROUGH THE
WEEKEND. SHOWER CHANCES LOOK TO START INCREASING SATURDAY AND
ESPECIALLY SUNDAY WITH LOCALLY HEAVY SHOWERS POSSIBLE. SEAS AND SURF
COULD START BUILDING SATURDAY, JULY 4TH AS SWELL FROM 95W APPROACHES
THE MARIANAS. SEAS AND SURF MAY BECOME HAZARDOUS AS SOON AS SATURDAY
NIGHT. THIS SITUATION WILL CONTINUE TO BE MONITORED CLOSELY.
TROPICAL SYSTEMS
INVEST 95W IS CURRENTLY DRAPED ACROSS MUCH OF THE NORTHERN MARSHALL
ISLANDS AS AN ELONGATED, DISORGANIZED DISTURBANCE, WITH ITS CENTER
LOCATED AROUND 8N165E, NEAR UJAE ATOLL. SCATTEROMETRY DATA AND
SATELLITE IMAGERY DEPICT A VERY BROAD, BUT STILL WEAK CIRCULATION
BEGINNING TO CONSOLIDATE ABOUT THIS AREA, EXTENDING WESTWARD TO
BEYOND POHNPEI AND EASTWARD TO THE NORTH OF MAJURO, ROUGHLY. THE
JOINT TYPHOON WARNING CENTER (JTWC) STILL RATES INVEST 95W AS
"MEDIUM" FOR DEVELOPMENT, MEANING IT WILL LIKELY DEVELOP INTO A
SIGNIFICANT TROPICAL CYCLONE (A TROPICAL DEPRESSION), BUT NOT WITHIN
24 HOURS. SATELLITE IMAGERY THIS AFTERNOON SHOWS BANDS OF FLARING
CONVECTION DEVELOPING ALONG 95W'S SOUTHWESTERN PERIPHERY, INCLUDING
OVER POHNPEI AND KOSRAE AND WRAPPING INTO ITS CENTER. HEAVY SHOWERS
AND THUNDERSTORMS ARE CURRENTLY BUILDING WITHIN THE SOUTHERLY FLOW
OVER AND SOUTH OF KWAJALEIN ATOLL, NEAR EAST OF THE CENTER. AREAS OF
DEEP, FLARING CONVECTION ARE MORE SPARSELY SEEN ACROSS THE NORTHERN
AND FAR EASTERN PERIPHERIES OF INVEST 95W, INCLUDING OVER MAJURO AND
THE NORTHERNMOST ATOLLS OF THE RMI. FOR NOW, MODELS FAVOR A GRADUAL
CONSOLIDATION OVER THE FAR NORTHWESTERN MARSHALL ISLANDS TONIGHT AS
95W SLOWLY ORGANIZES AND BEGINS TO MEANDER WEST-NORTHWEST, TO THE
NORTH OF KOSRAE AND LATER POHNPEI. INVEST 95W IS STILL CONSOLIDATING
AND REMAINS A VERY BROAD DISTURBANCE, AND UNTIL IT BECOMES MORE
ORGANIZED THERE REMAINS HIGH UNCERTAINTY AS TO ITS EXACT TRACK. THERE
IS INCREASING CONFIDENCE IN ITS POTENTIAL FOR DEVELOPMENT INTO A
LARGE, STRENGTHENING TROPICAL CYCLONE WHICH MAY EVENTUALLY BECOME A
TYPHOON. INVEST 95W IS BEING CLOSELY MONITORED FOR THE POTENTIAL OF
ANY IMPACTS TO THE MARIANAS IN THE COMING DAYS AS IT IS EXPECTED TO
GENERALLY MOVE WEST-NORTHWEST TO NORTHWEST, WITH A BROAD VARIETY OF
MODEL OUTCOMES. FOR MORE INFORMATION ON INVEST 95W, PLEASE REFER TO
THE SIGNIFICANT TROPICAL WEATHER ADVISORY FROM THE JOINT TYPHOON
WARNING CENTER (JTWC) UNDER WMO HEADER ABPW10 PGTW.
EASTERN MICRONESIA
THE FOCUS CONTINUES TO BE AROUND INVEST 95W, WHICH IS STILL RATED AS
MEDIUM FOR DEVELOPMENT FROM JTWC (THE JOINT TYPHOON WARNING CENTER).
VISIBLE IMAGERY SHOWS THE LLCC (LOW-LEVEL CIRCULATION CENTER) HAS
DEVELOPED JUST SOUTHWEST OF UJAE. CURRENTLY, MAJURO HAS MAINLY HAD A
LOT OF MID AND HIGH-LEVEL CONVECTIVE DEBRIS, BUT LITTLE HEAVY
RAINFALL OR STRONGER WIND GUSTS. WITH THAT SAID, AN ISOLATED HEAVIER
SHOWER OR TWO REMAIN POSSIBLE. KOSRAE HAS STARTED TO SEE THE "FRINGE
EFFECTS" OF THIS DEVELOPING SYSTEM, BUT OVERALL, TEMPORAL AND AREAL
CONCERNS LOOK SUFFICIENT TO NOT HAVE A HEADLINE IN EITHER LOCATION.
FOR POHNPEI, 95W IS CURRENTLY FORECAST TO PASS OVER 300 MILES NORTH
OF YOU, POSSIBLY AS A DEVELOPING TROPICAL STORM. WITH THAT SAID, IT
REMAINS UNCLEAR IF YOU'LL SEE A WEST-SOUTHWEST MONSOON FLOW DEVELOP
GIVEN HOW FAR NORTH IT'LL BE PASSING. ADDITIONALLY, THE MODEL MEAN
CONSENSUS FROM THE GEFS, ECENS, GOOGLE DEEPMIND SHOWS A MINIMAL TS
(TROPICAL STORM) AS IT DOES SO, WHICH MAY LIMIT THE TEMPORAL DURATION
OF ANY HEAVIER RAINFALL. AS SUCH, WE INCLUDED A HEADLINE IN THE
UPDATED SPECIAL WEATHER STATEMENT, BUT FOR NOW, WE REFRAINED FROM
INCLUDING IT IN THE FORECAST ITSELF. THE MODELS ALSO SHOWED A "DRY
SLOT" POSSIBLY PASSING OVER A GOOD CHUNK OF POHNPEI STATE, LOWERING
CONFIDENCE IN HOW LONG OF A HEAVY RAINFALL POTENTIAL YOU MIGHT SEE.
HOWEVER, THIS TOPIC WILL BE REVISITED WITH THE AFTERNOON FORECAST
PACKAGE TOMORROW.
LOOKING LONGER-TERM (THE FIRST HALF OF NEXT WEEK), THE BULK OF THE
NUMERICAL GUIDANCE PORTRAYS THE NET (NEAR-EQUATORIAL TROUGH) WILL
REMAIN SITUATED ACROSS THE REGION, WITH ADDITIONAL TROPICAL
DISTURBANCES (SURFACE TROUGHS) CROSSING THE AREA FROM TIME TO TIME.
THESE TROUGHS COULD MAINTAIN A FAIRLY UNSETTLED PATTERN FOR MUCH OF
NEXT WEEK.
AS FOR MARINE CONDITIONS, ASIDE FROM AN ISOLATED CONVECTIVELY-AIDED
WIND GUST, MAINLY GENTLE TO MODERATE WINDS CAN BE EXPECTED FOR
POHNPEI AND KOSRAE THROUGH MUCH OF THE FORECAST PERIOD, OCCASIONALLY
TOUCHING FRESH THRESHOLDS FROM TIME TO TIME. MAJURO LOOKS TO REMAIN
LIGHT TO GENTLE THROUGH THE FORECAST PERIOD. SEAS LOOK TO AVERAGE
BETWEEN 4 AND 6 FEET AREA-WIDE THROUGH EARLY NEXT WEEK.
WESTERN MICRONESIA
QUIETER CONDITIONS PREVAIL OVER PALAU THIS AFTERNOON AS THE NEARBY
MONSOON PATTERN SHIFTS WESTWARD AND AWAY WITH THE MOVEMENT OF JTWC'S
INVEST 96W, NOW LOCATED OVER THE PHILIPPINES. LIGHT AND VARIABLE
WINDS DEVELOPED OVER PALAU TODAY AS A COL AREA MOVED IN NEARBY, WHICH
ALLOWED ISLAND-EFFECT THUNDERSTORMS TO DEVELOP THIS AFTERNOON.
AFTERNOON ISLAND CONVECTION HAS BEEN INCLUDED IN PALAU'S WEDNESDAY
FORECAST AS THE LOCAL WIND FIELD REMAINS LIGHT, AND VERY BROAD
SOUTHWEST FLOW CONTINUES TO FUNNEL DEEP MOISTURE INTO THE REGION. TO
THE NORTHEAST, MOSTLY CLEAR CONDITIONS ARE SEEN OVER YAP PROPER,
WHICH IS EXPECTED TO REMAIN IN A DRY, GENTLE TRADE-WIND REGIME OVER
THE NEXT FEW DAYS. FAIRLY DRY CONDITIONS ALSO PREVAIL FOR CHUUK,
LOCATED WITHIN A BROAD COL REGION BETWEEN INVEST 95W OVER EASTERN
MICRONESIA AND A VERY WEAK NET CIRCULATION OVER YAP STATE. HOWEVER,
MODELS DEPICT SHOWERS BUILDING NEAR WENO OVERNIGHT AS CONVERGENCE
INCREASES NEARBY, ASSOCIATED WITH THE DEVELOPMENT OF INVEST 95W,
WHICH REMAINS A VERY BROAD, ELONGATED DISTURBANCE. THEREAFTER,
ALTHOUGH MODELS DEPICT A FAIRLY DRY PERIOD FOR CHUUK FOR SEVERAL
DAYS, STRENGTHENING WEST TO SOUTHWEST FLOW TO THE SOUTH OF 95W MAY
BRING INCREASINGLY WET WEATHER TOWARD THE END OF THE WEEK THROUGH THE
WEEKEND.
BENIGN MARINE CONDITIONS CONTINUE, WITH ALTIMETRY AND YAP BUOY DATA
SUGGESTING COMBINED SEAS BETWEEN 3 AND 4 FEET ACROSS MUCH OF THE
REGION. SOUTHWEST SWELL AT PALAU WILL BE OVERTAKEN BY AN EAST TO
NORTHEAST SWELL OVER THE NEXT DAY OR SO. CHUUK WILL SEE AN INCREASE
IN SEAS BY THE END OF THE WEEK, ASSOCIATED WITH AN INCREASE IN
NORTHEAST SWELL FROM DEVELOPING INVEST 95W. THE DEVELOPMENT OF INVEST
95W IS BEING CLOSELY MONITORED, AS MODELS SUGGEST THE POTENTIAL FOR
MARINE AND COASTAL HAZARDS TOWARD THE END OF THE WEEK FOR CHUUK.
GUM WATCHES/WARNINGS/ADVISORIES
GU...NONE.
MP...NONE.
MARIANAS WATERS...NONE.
MARIANAS: OGLE
EAST MICRONESIA: DOLL
WEST MICRONESIA: DECOU
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