227
FXPQ50 PGUM 061841
AFDGUM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
441 AM CHST SUN JUN 7 2026
MARIANAS UPDATE
NO CHANGES FOR THE MARIANAS, WHICH REMAIN IN A DRY TRADE-WIND REGIME.
LIGHT TO GENTLE EAST WINDS WILL COMBINE WITH SEAS 3 TO 4 FEET TO MAKE
FOR BENIGN SEA CONDITIONS, WHICH ARE LIKELY TO LAST AT LEAST THROUGH
THIS WEEK. THE FIRE DANGER IS LOW, BUT IT COULD BECOME MODERATE ON
TUESDAY.
EASTERN MICRONESIA UPDATE
NO CHANGES FOR POHNPEI OR MAJURO. FOR KOSRAE, JUST CORRECTED THE SKY
AND WEATHER RELATIONSHIP FOR TODAY THROUGH MONDAY NIGHT, BY MAKING
THE SHOWERS ISOLATED TODAY WHEN THE CLOUDS TO THE EAST ARE MOSTLY
CIRRUS. THEN, FOR TONIGHT THROUGH MONDAY NIGHT, MADE THE SHOWERS
SCATTERED WHILE THE SKIES BECAME MOSTLY CLOUDY. WINDS OF 5 TO 10
KNOTS AND SEAS OF 3 TO 4 FEET WILL LEAD TO BENIGN MARINE CONDITIONS
THROUGH THE ENTIRE FORECAST PERIOD.
WESTERN MICRONESIA UPDATE
NO CHANGES FOR WESTERN MICRONESIA, EXCEPT TO REDUCE HIGH TEMPERATURES
TODAY AT CHUUK. 89 DEGREES AND A 50 PERCENT CHANCE OF SHOWERS USUALLY
DON'T MIX, SO LOWERED THE HIGHS TO 88 DEGREES. WINDS OF 5 TO 10 KNOTS
AND SEAS OF 3 TO 4 FEET WILL LEAD TO BENIGN MARINE CONDITIONS THROUGH
THE ENTIRE FORECAST PERIOD.
PREV DISCUSSION
/ISSUED 511 PM CHST SAT JUN 6 2026/
MARIANAS SYNOPSIS...
SATELLITE IMAGERY REVEALS PARTLY CLOUDY SKIES AND ISOLATED SHOWERS
ACROSS THE MARIANAS THIS AFTERNOON. COMBINED SEAS ARE BETWEEN 3 TO 4
FEET AND A MODERATE RISK OF RIP CURRENTS EXISTS ALONG NORTH- AND
EAST-FACING REEFS.
DISCUSSION...
A SHALLOW TRADE-WIND TROUGH HAS PRODUCED PARTLY CLOUDY SKIES FOR MOST
OF THE MARIANAS, ESPECIALLY OVER SOUTHERN GUAM AND ADJACENT COASTAL
WATERS AS THE REINVIGORATED MOISTURE INTERACTS WITH ISLAND-EFFECT
HEATING. SHOWERS ARE ISOLATED IN COVERAGE AND TIMING, SO POPS WERE
KEPT AT 20 PERCENT FOR TONIGHT AS THE DRIER AIRMASS PERSISTS ACROSS
THE REGION FOR THE REST OF THE WEEKEND. WINDS ARE BEING OBSERVED
BETWEEN 10 TO 15 MPH AND ARE EXPECTED TO CONTINUE THROUGH THE REST
OF THE FORECAST PERIOD. AS WE ENTER THE NEW WEEK, A BROAD SURFACE
TROUGH MAY TRACK TOWARDS THE MARIANAS AS THE HIGH PRESSURE RIDGE
RETRACTS TO THE NORTH. THE REGION MAY SEE SCATTERED SHOWERS AND
MOSTLY CLOUDY SKIES BUILDING IN STARTING MONDAY AFTERNOON. MODEL
GUIDANCE IS IN MUCH DISAGREEMENT ON THE INTENSITY AND TIMING OF THIS
TROUGH, SO THERE IS A SLIGHT POSSIBILITY OF ISOLATED THUNDERSTORMS
SPATIALLY LIMITED TO GUAM AND ADJACENT COASTAL WATERS FOR THE SAME
TIME PERIOD. THE DRY TRADE-WIND REGIME COULD POSSIBLY MAKE A RETURN
STARTING MIDWEEK.
MARINE...
FOR THIS FORECAST PERIOD, A SECONDARY, WEAK, NORTHERLY SWELL WAS
INTRODUCED AS SIGNIFICANT WEATHER FEATURES TRAVERSE ACROSS THE MID-
LATITUDES FAR TO THE NORTH. THESE SWELL HEIGHTS ARE EXPECTED TO
REMAIN LIMITED TO 2 TO 3 FT IN THE FIRST HALF OF NEXT WEEK, BECOMING
NEGLIGENT IN THE SECOND HALF. THUS, COMBINED SEAS WILL STAY WITHIN
THE 3 TO 4 FT RANGE, POSSIBLY PEAKING TO 5 FT AROUND MONDAY NIGHT.
BUOY AND ALTIMETRY DATA CURRENTLY SUPPORT SEA HEIGHTS CAPABLE OF
PRODUCING 3 TO 5 FT SURF ALONG NORTH- AND EAST-FACING REEFS, SO
THERE REMAINS A MODERATE RISK OF RIP CURRENTS. THESE SURF CONDITIONS
ARE EXPECTED TO CONTINUE AT LEAST FOR THE NEXT SEVERAL DAYS.
EASTERN MICRONESIA...
A SURFACE TROUGH HAS AMPLIFIED TODAY BETWEEN KOSRAE AND POHNPEI, AND
THIS WILL KEEP SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS GOING
FOR POHNPEI THROUGH MONDAY. AT KOSRAE, WITH THE TROUGH MOVING AWAY
YOU CAN EXPECT JUST ISOLATED SHOWERS TONIGHT. HOWEVER, AN AREA OF
ENHANCED SURFACE CONVERGENCE TO YOUR EAST, ASSOCIATED WITH THE RE-
INVIGORATING ITCZ (INTER-TROPICAL CONVERGENCE ZONE) WILL BRING
SCATTERED SHOWERS AND A FEW THUNDERSTORMS BACK INTO YOUR FORECAST AS
EARLY AS TOMORROW (SUNDAY). THIS WILL THEN CONTINUE THROUGH MONDAY
BEFORE THE ACTIVITY DIMINISHES AGAIN. FINALLY AT MAJURO, A SURFACE
TROUGH JUST TO THE WEST OF YOU IS CLOSE ENOUGH TO KEEP SCATTERED
SHOWERS GOING IN YOUR FORECAST TONIGHT. THEN, A DECREASE IN SHOWER
COVERAGE IS ANTICIPATED FOR SUNDAY AND SUNDAY NIGHT, BEFORE
ADDITIONAL AREAS OF ENHANCED CONVERGENCE AND/OR SURFACE TROUGHS ONCE
AGAIN INCREASE YOUR RAINFALL POTENTIAL MONDAY ONWARD.
FOR THE MARINERS, LOOK FOR LIGHT TO GENTLE WINDS TO PERSIST THROUGH
THE FORECAST PERIOD, WITH SEAS OF 3 TO 5 FEET CONTINUING.
WESTERN MICRONESIA...
SATELLITE IMAGERY SHOWS SCATTERED SHOWERS OVER WENO AND CHUUK STATE,
AND ACROSS WESTERN YAP STATE. ISOLATED SHOWERS ARE SEEN ACROSS YAP
PROPER AND PALAU. ALTIMETRY SHOWS COMBINED SEAS BETWEEN 2 AND 5 FEET
ACROSS THE REGION.
THE MAIN TWO WEATHER FEATURES IMPACTING WESTERN MICRONESIA ARE THE
NEAR EQUATORIAL TROUGH (NET) AND A WEAK CIRCULATION. THE NET EXTENDED
NORTHWARD OVERNIGHT, WHERE IT MEETS A WEAK CIRCULATION SOUTH OF
POHNPEI, AND A WEAK CIRCULATION NORTHEAST OF WENO. WENO AND CHUUK
STATE CONTINUE TO BE WITHIN THE REGION OF CONVERGENCE, WHICH IS
KEEPING SHOWER COVERAGE SCATTERED THROUGH THE NEXT SEVERAL DAYS.
A WEAK SURFACE LOW WAS LOCATED NEAR 7N140E OR SOUTHEAST OF YAP
PROPER. CONVECTION HAS BEEN ONGOING AND WELL ORGANIZED TODAY WITH
CONTINUED IMPROVEMENTS THIS AFTERNOON. THIS CURRENT CIRCULATION
APPEARS TO BE OVER PERFORMING COMPARED TO THE PREVIOUS ECMWF AND GFS
SOLUTIONS. ALTHOUGH THE ENVIRONMENT IS FAVORABLE FOR DEVELOPMENT,
GUIDANCE SHOWS A WEAKENING OF THE WESTERLY WINDS SOUTH OF PALAU.
THIS LIMITS THE STORM'S POTENTIAL TO WIND ITSELF UP INTO A STRONGER
SYSTEM. NONETHELESS, SCATTERED TO NUMEROUS RAINFALL IS EXPECTED FOR
YAP OVER THE NEXT FEW DAYS. PALAU WILL GENERALLY SEE ISOLATED TO
SCATTERED SHOWERS THROUGH THE PERIOD WHILE ON THE FRINGE OF THE
CIRCULATION. IF WESTERLY WINDS REMAIN STRONGER THAN MODELED, THEN WE
WILL NEED TO WATCH THIS SYSTEM FOR FURTHER DEVELOPMENT.
OVERALL, LITTLE TO NO CHANGES TO THE MARINE FORECAST FROM THE
PREVIOUS PACKAGE. COMBINED SEAS ARE BETWEEN 2 AND 5 FEET AND LOOK TO
REMAIN BENIGN THROUGH THE PERIOD.
GUM WATCHES/WARNINGS/ADVISORIES
GU...NONE.
MP...NONE.
MARIANAS WATERS...NONE.
MARIANAS/EAST AND WEST MICRONESIA UPDATE: STANKO
MARIANAS: MESA
EAST MICRONESIA: DOLL
WEST MICRONESIA: WILLIAMS
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