524
FXPQ50 PGUM 101855 CCA
AFDGUM
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE TIYAN GU
455 AM CHST SUN JAN 11 2026
MARIANAS UPDATE
NO CHANGES WERE NEEDED AS THE FORECAST IS IN GOOD SHAPE. THE GRADIENT
WIND (WIND AT ABOUT ~1500 FEET) WAS 32 KNOTS LAST NIGHT, SO TODAY
WILL BE ANOTHER GUSTY DAY. WITH THAT SAID, SCATTEROMETER DATA DOES SO
A SLIGHT DECREASE IN SUSTAINED WINDS THAT SHOULD WORK THEIR WAY
INTO THE AREA LATER TONIGHT. WE'LL CONTINUE TO KEEP AN EYE ON THIS,
AS THE MORNING BALLOON LAUNCH SHOULD HELP US CLARIFY HOW QUICKLY THE
WINDS ARE DECREASING.
EASTERN MICRONESIA UPDATE
NO UPDATES WERE NEEDED THIS MORNING. HOWEVER, CONVECTION HAS FLARED
UP OVER POHNPEI AND KOSRAE, WITH SOME THUNDERSTORMS OCCURRING WITH
DECENT BURSTS OF LIGHTNING AS CLOUD TOPS COLL TO -75 DEGREES.
THIS IS WELL IN LINE WITH THE CURRENT FORECAST.
WESTERN MICRONESIA UPDATE
THE MAIN FORECAST UPDATES WERE TO ADD ISOLATED THUNDERSTORMS TO THE
FORECAST FOR TODAY, AND EXTEND THE SMALL CRAFT ADVISORY THROUGH 5 PM
THIS AFTERNOON AS ALTIMETRY SHOWED SEAS REMAIN NEAR 10 FEET.
ADDITIONALLY, ISOLATED TO AT TIMES SCATTERED THUNDERSTORMS HAVE
DEVELOPED ALONG THE NEAR-EQUATORIAL TROUGH THAT HAS "SET UP SHOP"
SOUTH OF KOROR, AS IT BISECTS PALAU NEAR HELEN'S REEF. AS SUCH,
CONVECTION MAY BE SOMEWHAT GREATER IN COVERAGE THERE, WITH FREQUENT
GUSTS TO 25 KNOTS PROBABLE.
PREV DISCUSSION
/ISSUED 702 PM CHST SAT JAN 10 2026/
MARIANAS SYNOPSIS...
THERE IS A SMALL CRAFT ADVISORY (SCA), HIGH SURF ADVISORY (HSA) AND
HIGH RISK OF RIP CURRENTS STATEMENT IN EFFECT.
SATELLITE IMAGERY SHOWS MOSTLY CLOUDY SKIES, WHILE RADAR IMAGERY
SHOWS FAST-MOVING ISOLATED TO SCATTERED SHOWERS MOVING SOUTH-
SOUTHWESTWARD ACROSS THE ISLANDS. ALTIMETRY SHOWS COMBINED SEAS OF 6
TO 8 FEET TO THE FAR EAST OF THE ISLANDS AND 9 TO 12 FEET TO THE FAR
WEST OF THE ISLANDS. IPAN BUOY DATA SHOWS HEIGHTS OF ABOUT 7 TO 8
FEET AND ABOUT 8 SECOND PERIODS.
DISCUSSION...
SATELLITE DERIVED PRECIPITABLE WATER (PWATS) SHOWS A FAIRLY DRY
PATTERN ACROSS THE REGION, WITH VALUES AMOUNTING TO 1.3 TO 1.6
INCHES. A FEW SHOWERS ARE TRYING TO DEVELOP WITHIN A SURGE IN THE
NORTHEAST TRADES, HOWEVER, THE UPPER EXTENT OF THE LOWER LAYERS AND
ABOVE HAVE A LARGE POCKET OF DRY AIR. THIS POCKET WILL MORE DIFFICULT
FOR SUSTAINED SHOWERS TO DEVELOP. WINDS HAVE BEEN GUSTY TODAY WITH
15 TO 20 MPH GUSTING TO 31 MPH. THESE WINDS ARE DUE TO A SHEAR LINE
OVER THE REGION. OVERALL, THIS DRIER AND GUSTIER TRADE-WIND PATTERN
IS EXPECTED TO CONTINUE WITH A SLIGHT INCREASE IN SHOWERS AROUND
WEDNESDAY.
MARINE/SURF...
MODERATE TO STRONG NORTHEAST WINDS WITH NEAR GALE GUSTS WILL
CONTINUE THROUGH THE WEEKEND. SEAS WILL BUILD TO 8 TO 10 FEET
TONIGHT, AND WILL CONTINUE THROUGH SUNDAY. THE TRADE SWELL IS
EXPECTED TO REMAIN AROUND THE 7 TO 8 FEET THROUGH THE END OF NEXT
WEEK. SEAS AND WINDS ARE ANTICIPATED TO FALL BELOW 10 FOOT SEAS AND
22 KNOT WINDS AROUND SUNDAY NIGHT, AND CONTINUE TO FALL TO AROUND 7
TO 8 FEET OVER THE BEGINNING OF NEXT WEEK. WE MAY SEE ANOTHER PULSE
IN NORTHERLY SWELL AROUND TUESDAY AND WEDNESDAY, TO AROUND 5
FEET, WHICH MAY BUILD SEAS BACK UP TO THESE THRESHOLDS. CURRENTLY,
THERE IS A HIGH RISK OF RIP CURRENTS ALONG NORTH AND EAST FACING
REEFS, AND A MODERATE ALONG WEST FACING REEFS. THE SURF ALONG NORTH
AND EAST FACING REEFS ARE ANTICIPATED TO FLUCTUATE BETWEEN 7 TO 10
FEET THROUGH MUCH OF NEXT WEEK. A HIGH SURF ADVISORY ALONG NORTH-
FACING REEFS AND A HIGH RIP CURRENT RISK ALONG NORTH- AND EAST-
FACING REEFS REMAINS IN EFFECT THROUGH AT LEAST TUESDAY AFTERNOON.
EASTERN MICRONESIA...
THE LATEST SATELLITE DATA SHOWS PARTLY CLOUDY SKIES WITH SPOTTY
LIGHT SHOWERS FOR MAJURO, MOSTLY CLOUDY SKIES WITH ISOLATED SHOWERS
AT POHNPEI AND MOSTLY CLOUDY SKIES WITH SCATTERED SHOWERS OVER
KOSRAE. ALTIMETRY SHOWS SEAS BETWEEN 5 AND 7 FEET FOR POHNPEI AND
KOSRAE. POHNPEI BUOY SHOWS SEAS OF 7 TO 8 FEET, WITH KOSRAE BUOY
SHOWING SEAS OF 3 TO 5 FEET. ALTIMETRY SHOWS SEAS OF 6 TO 8 FEET
EAST OF MAJURO.
THE OVERALL PATTERN FOR EASTERN MICRONESIA IS LOOKING A BIT MORE ON
THE WET SIDE FOR THE NEXT SEVERAL DAYS. NOTHING REALLY SPECTACULAR,
RAINFALL WISE, BUT ENOUGH TO ESTABLISH A TREND. THERE ARE TWO TRADE-
WIND TROUGHS CURRENTLY MOVING THROUGH THE REGION. THE FIRST IS
BETWEEN KOSRAE AND KWAJALEIN AND IS PRODUCING SCATTERED SHOWERS OVER
KOSRAE THIS AFTERNOON. A FEW THUNDERSTORMS ARE POSSIBLE AT KOSRAE
OVERNIGHT. THIS TROUGH WILL TRACK WEST OVER THE NEXT COUPLE OF DAYS,
BRINGING INCREASED CONVECTION TO POHNPEI SUNDAY. MODELS ALSO INDICATE
THAT A BAND OF CONVERGENCE DEVELOPING EAST OF THE TROUGH WILL
STRENGTHEN AND SPREAD WEST ALONG WITH THE TROUGH, MAINTAINING
CONVECTION ACROSS KOSRAE AND POHNPEI FOR A COUPLE OF DAYS. THE SECOND
TROUGH IS FOUND EAST OF THE MARSHALLS AND LOOKS TO BRING INCREASED
SHOWERS TO MAJURO SUNDAY. THIS TROUGH WILL ALSO MOVE TOWARDS KOSRAE
AND POHNPEI TO HELP STRENGTHEN THE CONVERGENCE OVER THE REGION AND
TO MAINTAIN CONVECTION AT POHNPEI AND KOSRAE. AROUND THE BEGINNING OF
NEXT WEEK, MODELS FAVOR THE DEVELOPMENT OF A WEAK INTER-TROPICAL
CONVERGENCE ZONE (ITCZ) ACROSS THE REGION, MAINLY SOUTH OF THE
FORECAST POINTS. HOWEVER,THE ITCZ LOOKS TO WAVER NORTH AND SOUTH FOR
A FEW DAYS BEFORE DISSIPATING, BRINGING PERIODS OF INCREASED
CONVECTION TO ALL THREE FORECAST POINTS.
FOR THE MARINE FORECAST, THE MAIN CHANGE IS FOR TODAY AT POHNPEI.
ANOTHER PULSE OF BUILDING NORTH-NORTHEAST SWELL HAS PUSHED INTO THE
REGION AND WILL PRODUCE HAZARDOUS SURF ALONG NORTH FACING REEFS
TONIGHT INTO SUNDAY AFTERNOON. THEREFORE, A HIGH SURF ADVISORY WAS
ISSUED FOR TONIGHT THROUGH SUNDAY AFTERNOON. OTHERWISE, NO MAJOR
CHANGES TO THE MARINE FORECAST. WE ARE STILL LOOKING AT CONDITIONS
HAZARDOUS TO SMALL CRAFT OPERATIONS MOVING INTO MAJURO AS EARLY AS
MONDAY NIGHT AND INTO POHNPEI AND KOSRAE TUESDAY, WITH THESE
CONDITIONS CONTINUING THROUGH THURSDAY. THIS WILL BE MONITORED OVER
THE NEXT COUPLE OF DAYS TO DETERMINE THE NEED FOR A SMALL CRAFT
ADVISORY FOR ALL THREE MARINE ZONES AND A HIGH SURF ADVISORY FOR EAST
FACING REEFS AT KOSRAE.
WESTERN MICRONESIA...
A NEAR-EQUATORIAL TROUGH (NET) CONTINUES TO STRETCH ACROSS THE
SOUTHERN HALF OF THE REGION. ACROSS YAP AND PALAU, SATELLITE
OBSERVATIONS SHOW ISOLATED TO SCATTERED SHOWERS WITHIN A MODERATE TO
STRONG NORTHEAST TRADE FLOW, AND WITH CONVECTION INCREASING
SOUTHWEST OF THE MAIN ISLANDS OF PALAU AS THE TRADE-WIND PATTERN
COLLIDES WITH THE NET. OVER THE NEXT FEW DAYS, MODEL GUIDANCE STILL
INDICATES AN UNSETTLED PATTERN NEXT WEEK AS A POSSIBLE DISTURBANCE OR
BROAD CIRCULATION BEGINS TO TAKE SHAPE, PASSING SOUTH OF PALAU
MONDAY AND TUESDAY AND POSSIBLY BECOMING MORE DEVELOPED AS IT PASSES
WEST OF PALAU WEDNESDAY. WITH THIS FORECAST UPDATE, INCREASED POPS
MONDAY AFTERNOON THROUGH WEDNESDAY TO EXPECT NUMEROUS TO WIDESPREAD
SHOWERS AND ISOLATED THUNDERSTORMS. OVER THE NEXT COUPLE DAYS, THERE
MAY BE ADDITIONAL UPDATES TO THE TIMING AND INTENSITY OF SHOWERS AND
THUNDERSTORMS AS WE CONTINUE TO MONITOR THE DEVELOPMENT OF THIS
DISTURBANCE. FOR CHUUK, AN INCREASE IN TRADE-WIND CONVERGENCE MAY
OCCUR IN THE WAKE OF THIS DISTURBANCE, SO CONTINUE TO EXPECT
SCATTERED SHOWERS, WITH A PEAK IN SHOWERS ON MONDAY.
ALTIMETRY AND SCATTEROMETRY DATA CONTINUES TO SHOW HAZARDOUS WINDS
AND SEAS AT YAP WITH CONDITIONS REACHING HAZARDOUS THRESHOLDS OF 22
KT AND SEAS OF 10 FT AT PALAU EARLIER TODAY. THE SMALL CRAFT
ADVISORY FOR YAP REMAINS IN EFFECT THROUGH AT LEAST EARLY MONDAY
AFTERNOON AND A SMALL CRAFT ADVISORY WAS ISSUED FOR PALAU THIS
AFTERNOON. A SLIGHT DECREASE IN WIND-DRIVEN WAVES AND NORTHEAST SWELL
IS EXPECTED OVERNIGHT AT PALAU, ALLOWING FOR COMBINED SEAS TO
DECREASE BELOW HAZARDOUS LEVELS OF 10 FEET BY SUNDAY MORNING. WITH A
POSSIBLE DISTURBANCE PASSING TO THE SOUTH MONDAY AND TUESDAY, THIS
MAY BRING ANOTHER INCREASE IN WINDS AND PRODUCE CHOPPY, ELEVATED
SEAS, POSSIBLY NEEDING TO REISSUE OR EXTEND THE ADVISORY AT PALAU AND
YAP. LARGE NORTHEAST SWELL CONTINUES TO PRODUCE HAZARDOUS SURF OF 9
TO 12 FEET THROUGH AT LEAST EARLY MONDAY MORNING. HOWEVER, THE
COMBINATION OF DOMINANT NORTHEAST TRADE SWELL AND BACKGROUND NORTH
SWELL MAY PROLONG HAZARDOUS SURF FOR ANOTHER DAY OR TWO, POSSIBLY
NEEDING ANOTHER EXTENSION TO THE ADVISORY.
GUM WATCHES/WARNINGS/ADVISORIES
GU...HIGH RIP CURRENT RISK THROUGH TUESDAY AFTERNOON FOR GUZ001.
HIGH SURF ADVISORY UNTIL 4 PM CHST TUESDAY FOR GUZ001.
MP...HIGH RIP CURRENT RISK THROUGH TUESDAY AFTERNOON FOR MPZ001>003.
HIGH SURF ADVISORY UNTIL 4 PM CHST TUESDAY FOR MPZ001>003.
SMALL CRAFT ADVISORY UNTIL 6 PM CHST THIS EVENING FOR MPZ001>003.
MARIANAS WATERS...SMALL CRAFT ADVISORY UNTIL 6 PM CHST THIS EVENING FOR PMZ151>154.
MARIANAS/EAST AND WEST MICRONESIA UPDATE: DOLL
MARIANAS: BOWSHER
EAST MICRONESIA: KLEESCHULTE
WEST MICRONESIA: CRUZ
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