693
FXPQ50 PGUM 011905
AFDGUM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
505 AM CHST TUE JUN 2 2026
MARIANAS UPDATE
THE INHERITED FORECAST WAS IN FINE SHAPE FOR TODAY, SO NO CHANGES
WERE NEEDED. A DRY TRADE-WIND REGIME REMAINS IN PLACE. A DECREASE IN
TRADE WINDS COULD INTRODUCE ISLAND SHOWERS EITHER OR BOTH OF
WEDNESDAY AND THURSDAY. THAT LEAVES ME A LITTLE CONFUSED WHY IT'S
WEDNESDAY NIGHT THAT MENTIONS SCATTERED SHOWERS, PROBABLY SOMETHING
WENT SLIGHTLY WRONG. WILL LEAVE THAT FOR THE DAY SHIFT TO SORT OUT.
THE WINDS TODAY WILL STILL BE A LITTLE TOO STRONG, WILL LIKELY JUST
GET A CLOUD LINE OFF THE ISLANDS. OTHERWISE, COMBINED SEAS OF 3 TO 5
FEET WILL LIKELY GRADUALLY DIMINISH, POSSIBLY PLUMBING 1 TO 3 FEET IN
A WEEK OR TWO. A MODERATE RISK OF RIP CURRENTS WILL BECOME LOW BY
THURSDAY. THE FIRE DANGER IS LOW AND WILL REMAIN SO FOR AT LEAST A
WEEK.
EASTERN MICRONESIA UPDATE
MAJURO HAD TODAY'S CLOUDS UPGRADED FROM PARTLY SUNNY TO MOSTLY
CLOUDY. SHOWERS WERE UPGRADED FROM SCATTERED AT 50 PERCENT TO
NUMEROUS AT 70 PERCENT. THIS WAS BASED ON SATELLITE TRENDS, METAR
OBSERVATIONS AND MOS VALUES. MEANWHILE, KOSRAE AND POHNPEI HAD THEIR
WIND DIRECTIONS CHANGED FOR TODAY, FROM WEST TO VARIABLE SINCE THE
METAR OBSERVATIONS WERE SHOWING EAST.
WESTERN MICRONESIA UPDATE
NO CHANGE WAS MADE AT YAP OR CHUUK. THE WEATHER LOOKS IMPROVED AT
CHUUK AT THIS TIME, BUT CLOUDS AND SHOWERS ARE APPROACHING, SO LEFT
THE FORECAST ALONE WITH SCATTERED AT 30 PERCENT. YAP'S FORECAST WAS
ISOLATED AT 20 PERCENT, AND IT LOOKS LIKE IT TOO ON SATELLITE IMAGES.
LASTLY, KOROR WAS ADJUSTED FROM SCATTERED AT 30 PERCENT TO ISOLATED
AT 20 PERCENT, BECAUSE THEIR SATELLITE IMAGE IS LOOKING ALMOST THE
SAME AS YAP'S.
PREV DISCUSSION
/ISSUED 512 PM CHST MON JUN 1 2026/
MARIANAS SYNOPSIS...
A DRY, WEAK TRADE WIND PATTERN CONTINUES AS ISOLATED SHOWERS ARE
VISIBLE OVER ALL OF THE MARIANAS. THIS IS EXPECTED TO CONTINUE FOR
THE ENTIRE WEEK. A DECREASE IN TRADE WINDS MAY ALLOW FOR ISLAND
EFFECT SHOWERS IN THE AFTERNOON FOR PART OF GUAM TUESDAY. A TRADE
WIND TROUGH AND A FURTHER DECREASE IN TRADE WINDS MAY ALLOW SCATTERED
SHOWERS AND ISLAND EFFECT SHOWERS FOR ALL THE MARIANAS BY WEDNESDAY.
COMBINED SEAS OF 3 TO 5 FEET WILL REMAIN STEADY THROUGH TONIGHT
BEFORE DECREASING SLOWLY.
DISCUSSION...
WEAK TRADE WIND SHOWERS ARE MAKING THEIR WAY OVER THE MARIANAS THIS
AFTERNOON. MOISTURE IS EXPECTED TO STAY HIGH ENOUGH FOR THIS PATTERN
TO CONTINUE FOR MUCH OF THE WEEK. WINDS SHOULD BE LIGHT ENOUGH FOR
ISLAND EFFECT SHOWERS TO DEVELOP OVER THE WEST SIDE OF GUAM FROM APRA
HARBOR SOUTH TO MALESSO, SO SCATTERED SHOWERS ARE IN THE FORECAST
FOR THAT AREA. SCATTERED SHOWERS ARE EXPECTED FOR ALL THE MARIANAS BY
WEDNESDAY DUE TO FURTHER WEAKENING OF THE WINDS AND POTENTIALLY
INCREASED MOISTURE FROM A TRADE WIND TROUGH MOVING THROUGH. ISLAND
EFFECT SHOWERS MAY CONTINUE THROUGH THE END OF THE WEEK IF MOISTURE
IS SUFFICIENT ENOUGH.
MARINE...
MODELS, COASTAL BUOYS, SOFAR BUOYS, AND SPOTTER OBSERVATIONS
INDICATE THAT SURF IS HIGH ENOUGH TO INDUCE A MODERATE RISK OF RIP
CURRENTS ALONG EAST FACING REEFS OF THE MARIANAS THROUGH WEDNESDAY
AND NORTH AND WEST FACING REEFS THROUGH AT LEAST TONIGHT. COMBINED
SEAS OF 3 TO 5 FEET WILL PERSIST THROUGH AT LEAST MONDAY NIGHT
BEFORE STARTING TO SLOWLY DECREASE. THE DOMINANT SWELLS ARE THE
EASTERLY TRADE WIND SWELL AND THE WESTERLY SWELL FROM DISTANT
TYPHOON JANGMI. WINDS ARE DECREASING TO LIGHT TO GENTLE TONIGHT,
POTENTIALLY BECOMING LIGHT BY TUESDAY NIGHT.
EASTERN MICRONESIA...
LATEST SATELLITE IMAGERY SHOWS CLOUDY SKIES WITH NUMEROUS SHOWERS
AND ISOLATED THUNDERSTORMS OVER KOSRAE, AND MOSTLY CLOUDY SKIES WITH
SCATTERED SHOWERS TO THE SOUTHEAST OF POHNPEI. AT MAJURO, ISOLATED
SHOWERS ARE PRESENT WITH INCREASING CLOUDS AND CONVECTION OVER THE
LAST COUPLE OF HOURS. ALTIMETRY SHOWS SEAS BETWEEN 2 AND 4 FEET FOR
POHNPEI AND KOSRAE AND 3 TO 5 FEET FOR MAJURO.
MODEL GUIDANCE IS HAVING A DIFFICULT TIME WITH THE NEAR-EQUATORIAL
TROUGH (NET). LATEST SATELLITE TRENDS SHOW THE NET IS NOW FARTHER
NORTH THAN PREVIOUSLY EXPECTED. THEREFORE, CONVECTION HAS INCREASED
ACROSS KOSRAE, WITH NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS OVER
THE ISLAND AND WATERS. THIS LOOKS TO CONTINUE THROUGH TONIGHT WHILE
CONVECTION INCREASES WESTWARD INTO POHNPEI. MAINTAINED POPS
(PROBABILITY OF PRECIPITATION) IN THE SCATTERED RANGE OF 30 TO 50
PERCENT THROUGH THE WEEK FOR POHNPEI, WITH THE SAME FOR KOSRAE
BEGINNING TUESDAY MORNING. THIS IS DUE TO THE NET REMAINING OVER THE
REGION WITH WEAK TRADE-WIND TROUGHS MOVING THROUGH AND INTERACTING
WITH THE NET. OVERALL, THE PATTERN LOOKS TO BE A BIT MORE WET THAN
THE PREVIOUS FORECAST. FOR MAJURO, ISOLATED SHOWERS PREVAIL OVER THE
MARSHALLS FOR NOW. HOWEVER, INCREASING CONVERGENCE ALONG A WEAK
SOUTHWEST TO NORTHEAST ORIENTED TROUGH IS INCREASING AND SATELLITE
TRENDS SHOW INCREASING CONVECTION ACROSS MAJURO. MAJURO LOOKS TO
REMAIN ON THE EASTERN END OF THE MAIN CONVECTION AND CAN EXPECT POPS
TO FLUCTUATE BETWEEN 20 AND 30 PERCENT INTO THE WEEKEND.
NO CHANGES TO THE MARINE FORECAST. FAIRLY BENIGN CONDITIONS ARE
EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE WEEK INTO THE
WEEKEND. MOSTLY LIGHT TO GENTLE WINDS WITH SEAS BETWEEN 2 AND 4 FEET
FOR POHNPEI AND KOSRAE AND BETWEEN 4 AND 5 FEET FOR MAJURO.
WESTERN MICRONESIA...
A NEAR-EQUATORIAL TROUGH (NET) EXTENDS BETWEEN PALAU AND YAP PROPER
TO A BROAD DISTURBANCE IN SOUTHEASTERN YAP STATE NEAR 4N146E, THEN
CURVES NORTHEASTWARD TO PASS SOUTH OF CHUUK LAGOON. AN AREA OF
SCATTERED SHOWERS HAVE PUSHED SOUTHWEST OF YAP PROPER DUE TO A
SLIGHT SOUTHWARD SHIFT IN THE NET, WITH CIMSS MIMIC PRECIPITABLE
WATER IMAGERY SHOWING RELATIVELY DRIER AIR OF 1.7 INCHES BEGINNING TO
MOVE OVER YAP PROPER THIS AFTERNOON. MAINLY ISOLATED SHOWERS ARE
EXPECTED TONIGHT THROUGH THURSDAY FOR YAP. ISOLATED TO SCATTERED
SHOWERS LINGER ACROSS PALAU THROUGH AT LEAST TUESDAY AFTERNOON DUE
TO THE PROXIMITY OF THE NET AXIS AND RELATIVELY MOIST
SOUTHWESTERLIES. THE NET DISTURBANCE LOOKS TO DRIFT NORTHWEST THROUGH
YAP STATE, POSSIBLY WEAKENING AROUND MIDWEEK, HOWEVER, THIS MAY
STILL PROMOTE SPOTTY SHOWERS NEAR YAP AND PALAU THROUGH LATE WEEK. A
PORTION OF THE NET REMAINS FAIRLY ACTIVE NEAR CHUUK THIS WEEK, WITH
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUING THROUGH MUCH
OF THE WEEK, WITH A PEAK IN NUMEROUS SHOWERS ON WEDNESDAY.
BENIGN MARINE CONDITIONS ARE EXPECTED THIS WEEK. ALTIMETRY DATA
SHOWS SEAS AROUND 4 TO 5 FEET. AS NORTHWEST AND WEST-SOUTHWEST
SWELLS CONTINUE TO DIMINISH, COMBINED SEAS ARE EXPECTED TO SUBSIDE TO
3 TO 4 FEET. LIGHT TO GENTLE WINDS BECOME LIGHT AND VARIABLE FOR
PALAU AND CHUUK STARTING TUESDAY AND LIGHT EASTERLY WINDS ARE
EXPECTED FOR YAP STARTING TUESDAY NIGHT.
GUM WATCHES/WARNINGS/ADVISORIES
GU...NONE.
MP...NONE.
MARIANAS WATERS...NONE.
MARIANAS/EAST AND WEST MICRONESIA UPDATE: STANKO
MARIANAS: OGLE
EAST MICRONESIA: KLEESCHULTE
WEST MICRONESIA: CRUZ
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