Home > Products > Valid Products > AFD

000
FXPQ60 PGUM 210553
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
353 PM CHST SUN DEC 21 2014

.MARIANAS SYNOPSIS...
FRESH TO STRONG TRADE WINDS AND ISOLATED LIGHT SHOWERS ARE PRESENT
ACROSS THE MARIANAS AND FOR SEVERAL HUNDRED MILES UPSTREAM TO THE
EAST. SEAS OF 9 TO 10 FEET ARE INDICATED AT THE RITIDIAN AND IPAN
BUOYS.

&&

.DISCUSSION...
REFRESHED THE WIND GRIDS FROM THE LATEST GUIDANCE...BUT NO LARGE
CHANGES TO THE FORECASTS RESULTED. FRESH TO STRONG WINDS WILL DROP
OFF SLIGHTLY MONDAY AND MONDAY NIGHT...THEN RAMP BACK UP TUESDAY
AND WEDNESDAY WITH BREEZY CONDITIONS RETURNING. SHOWERS WILL BE
ISOLATED THE NEXT FEW DAYS...WITH THE BEST CHANCE OF A SHOWER LATE
TONIGHT AND AGAIN TUESDAY AND TUESDAY NIGHT.

&&

.MARINE/SURF...
AS MENTIONED ABOVE...WINDS WILL DROP A BIT MONDAY AND MONDAY
NIGHT...THEN BECOME FRESH TO STRONG AGAIN FOR TUE-THUR. BUT COMBINED
SEAS WILL REMAIN AT 9 TO 11 FEET OR SO...WITH SOME 12-FOOT SEAS
LIKELY IN THE EASTERN WATERS TUE NIGHT INTO THURSDAY. THEREFORE...
HAVE EXTENDED THE SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT.

THE HIGH SURF ADVISORY FOR NORTH FACING REEFS IS NOW HISTORY...BUT
A NEW ADVISORY IS LIKELY BY WEDNESDAY ALONG EAST FACING REEFS AS
RENEWED TRADE-WIND SWELL REACHES 9 FEET OR MORE.

&&

.EASTERN MICRONESIA...
MODERATE TO FRESH TRADE WINDS ARE EXPECTED TO CONTINUE OVER THE
REGION THROUGH THE END OF THE WEEK. FAIR WEATHER HAS RETURNED TO
POHNPEI THIS AFTERNOON AND IS EXPECTED TO CONTINUE THROUGH TUESDAY
MORNING. A WEAK TRADE-WIND DISTURBANCE OVER THE MARSHALLS IS SLOWLY
PROGRESSING WESTWARD AND IS EXPECTED TO BRING INCREASING CONVECTION
TO MAJURO LATE TONIGHT. THIS SYSTEM WILL MOVE WESTWARD BRINGING
UNSTABLE CONDITIONS TO KOSRAE AND POHNPEI MONDAY WITH SCATTERED
SHOWERS EXPECTED AT KOSRAE A LITTLE LATER THAN THE PREVIOUS FORECAST.
ONCE THIS DISTURBANCE AND THE CONVERGING WINDS BEHIND IT CLEAR OUT
OF THE REGION...FAIR CONDITIONS ARE EXPECTED TO RETURN TO MAJURO
TUESDAY AND TO KOSRAE AND POHNPEI BY THURSDAY.

LATEST ALTIMETRY AND WAVE MODELS INDICATE LARGE EAST-NORTHEAST
TRADE-WIND SWELL WILL CONTINUE TO BUILD OVER THE ENTIRE REGION. THIS
WILL MAINTAIN SEA HEIGHTS AT LEVELS THAT ARE HAZARDOUS TO SMALL
CRAFT AT POHNPEI AND MAJURO THROUGH THE WEEK. SEAS ARE EXPECTED TO
INCREASE TO HAZARDOUS LEVELS FOR KOSRAE MONDAY MORNING. HAZARDOUS
SURF OF 7 TO 9 FEET IS ALREADY PRESENT AT KOSRAE AND IS EXPECTED TO
CONTINUE TO BUILD THROUGH THE NEXT DAY OR TWO...REACHING LEVELS OF 8
TO 11 FEET BY TUESDAY. AS THE SEAS CONTINUE TO BUILD OVER THE
REGION...HAZARDOUS SURF CONDITIONS ARE LIKELY AT MAJURO MONDAY AND
POHNPEI TUESDAY. THESE CONDITIONS WILL COINCIDE WITH THE SPRING HIGH
TIDES AT MAJURO MAKING COASTAL INUNDATION LIKELY ACROSS MAJURO AND
NEARBY ATOLLS. RESIDENTS ON ALL THE MENTIONED LOCATIONS NEED TO STAY
ALERT TO THE LATEST ADVISORIES ISSUED BY THE NATIONAL WEATHER SERVICE
AND INSTRUCTIONS FROM THEIR LOCAL EMERGENCY MANAGEMENT OFFICES.

&&

.WESTERN MICRONESIA...
A BAND OF CONVERGENCE OVER CHUUK IS MAINTAINING ISOLATED SHOWERS
OVER WENO THIS AFTERNOON. AS THE BAND CONTINUES TO DRIFT
WESTWARD...EXPECT FAIR WEATHER TO RETURN TO CHUUK FOR THE BEGINNING
OF THE WEEK. A TRADE-WIND DISTURBANCE WILL APPROACH CHUUK FROM
EASTERN MICRONESIA ON TUESDAY...BRINGING WET CONDITIONS BACK TO THE
STATE FOR A COUPLE OF DAYS. AS THIS DISTURBANCE MOVES ON TO THE
WEST...FAIR WEATHER WILL RETURN TO CHUUK FOR THE END OF THE WEEK.

TRADE-WIND CONVERGENCE IS GENERATING SCATTERED SHOWERS AND A FEW
THUNDERSTORMS NORTH OF KOROR AND EAST OF YAP THIS AFTERNOON. THIS
BAND OF CONVERGENCE AND ASSOCIATED SHOWERS WILL CONTINUE TO DRIFT
WESTWARD THROUGH MONDAY NIGHT...BUT WILL REMAIN CLOSE ENOUGH TO
BOTH LOCATIONS TO KEEP A SLIGHT CHANCE OF THUNDER IN THE FORECASTS.
FAIR CONDITIONS ARE EXPECTED TO PUSH IN FROM CHUUK BY TUESDAY AND
CONTINUE FOR A COUPLE OF DAYS. FOR THE LAST HALF OF THE WEEK...A
TRADE-WIND DISTURBANCE IS EXPECTED TO MOVE IN FROM CHUUK TO BRING
ANOTHER ROUND OF UNSETTLED WEATHER TO BOTH YAP AND KOROR.
MAINTAINED THE FORECAST FOR ISOLATED SHOWERS FOR NOW...BUT IF
CONDITIONS DEVELOP AS PREDICTED BY THE MODELS...SCATTERED SHOWERS
ARE A POSSIBILITY.

BUILDING TRADE-WIND SWELL AND WIND WAVES HAS CAUSED SEA HEIGHTS TO
REACH HAZARDOUS LEVELS FOR SMALL CRAFT OPERATION ACROSS CHUUK. SEAS
ARE EXPECTED TO CONTINUE TO BUILD OVER THE NEXT COUPLE OF DAYS AND
COULD PRODUCE HAZARDOUS SURF CONDITIONS AT CHUUK BY TUESDAY.
ALTHOUGH SEAS HAVE SUBSIDED A BIT AT YAP AND KOROR...HAZARDOUS
CONDITIONS ARE POSSIBLE AGAIN LATER IN THE WEEK AS THE LARGER
TRADE-WIND SWELL APPROACH THE REGION FROM CHUUK.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...SMALL CRAFT ADVISORY UNTIL 6 AM CHST FRIDAY FOR
     PMZ151>154.

&&

$$

MIDDLEBROOKE/KLEESCHULTE







000
FXPQ60 PGUM 202123
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
723 AM CHST SUN DEC 21 2014

.MARIANAS SYNOPSIS...EAST TRADE-WINDS AND A FEW SHOWERS PREVAILED
ACROSS THE MARIANAS TODAY. A FEW THUNDERSTORMS MOVED SOUTH OF GUAM
DURING THE MORNING.

&&

.DISCUSSION...
LITTLE CHANGE MADE TO FORECAST. THE HIGH PRESSURE AREA THAT
HELPED PRODUCE STRONG WINDS SATURDAY IS MOVING FURTHER AWAY.
WINDS SHOULD BE LESS TODAY THAN YESTERDAY AND SHOULD DECREASE
FURTHER MONDAY. THIS WILL BE A SHORT LULL AS WINDS ARE EXPECTED
TO AGAIN INCREASE TUESDAY AS ANOTHER HIGH PRESSURE AREA WILL MOVE
OFF ASIA. MODELS DEPICT A FEW TRADE-WIND DISTURBANCES PASSING
ACROSS THE LOCAL AREA THROUGH AT LEAST MONDAY NIGHT. EXPECT
PERIODS OF MOSTLY CLOUDY SKIES SHOWERS DURING THAT TIME.

AN AREA OF SHOWERS AND THUNDERSTORMS MOVED ACROSS THE COASTAL
WATERS SOUTH OF GUAM DURING THE MORNING. LIGHTNING WAS OBSERVED
DURING THE MORNING HOURS BEFORE SUNRISE. THIS AREA IS SMALL AND
EXPECT IT TO REMAIN SOUTH OF GUAM. ALSO BELIEVE THEY WILL PERSIST
ONLY THROUGH THE MORNING HOURS AND THEY WILL EITHER DIE OUT OR
MOVE OUT WEST OF THE LOCAL AREA.

&&

.MARINE...
AN EAST TRADE-WIND SWELL AND A NORTH SWELL WILL PERSIST THROUGH
THE FORECAST. RITIDIAN BUOY DATA INDICATES THE NORTH SWELL HAS
DECREASED AND IS EXPECTED TO CONTINUE TO DECREASE THROUGH THE
DAY. SURF WILL REMAIN HAZARDOUS ON NORTH FACING REEFS THROUGH THE
MORNING BEFORE FALLING BELOW HAZARDOUS LEVELS THIS AFTERNOON.

WINDS ARE STILL HIGH ENOUGH TO BE HAZARDOUS TO SMALL CRAFT AND
WILL REMAIN THAT WAY THROUGH THE DAY. WINDS SHOULD DECREASE
TONIGHT. EVEN THROUGH WINDS WILL DECREASE COMBINED SEAS WILL NOT.
EXPECT SEAS TO BE AT OR ABOVE SMALL CRAFT LEVELS THROUGH
WEDNESDAY. MODEL PROJECTIONS SHOW THAT SEAS WILL REMAIN ABOVE
SMALL CRAFT CRITERIA AFTER WEDNESDAY. MORE THAN LIKELY THE SMALL
CRAFT ADVISORY WILL BE EXTENDED PAST WEDNESDAY MORNING.

&&

.EASTERN MICRONESIA...
A LARGE DOME OF HIGH PRESSURE SLIDING EASTWARD FROM NORTH OF
MINAMI TORI SHIMA WILL CONTINUE TO CHANNEL FRESH TRADE WINDS
ACROSS THE REGION FOR THE NEXT FEW DAYS. A PERSISTENT UPPER-LEVEL
TROUGH IS ALSO ANTICIPATED TO LINGER ACROSS THE AREA NEAR 9N MOST
OF THIS WEEK. INCREASING TRADE CONVERGENCE IS GOING TO COUPLE
WITH MODEST DIVERGENT FLOW ALOFT TO TRIGGER ISOLATED
THUNDERSTORMS NEAR CHUUK... POHNPEI AND A FEW SHOWERS FOR KOSRAE
THRU TONIGHT. BY TONIGHT...THE CORE OF THE TRADES WILL PROVIDE
FAIR WEATHER FOR CHUUK AND POHNPEI. FARTHER EAST...A TRADE
DISTURBANCE IS SLOWLY PROGRESSING WESTWARD UNDERNEATH THE SAME
HIGH TOWARD THE MARSHALL ISLANDS THIS MORNING. THIS DISTURBANCE
WILL ALSO TAKE ADVANTAGE FROM THE PRESENCE OF THE UPPER TROUGH
AND SPARK OFF PERIODIC CONVECTION NEAR MAJURO BY LATER TONIGHT.
AS IT PUSHES FARTHER WESTWARD...UNSTABLE CONDITIONS WILL PROLONG
NEAR KOSRAE THRU TUESDAY AND REACH POHNPEI...CHUUK TOWARD
MIDWEEK. AFTER MIDWEEK...ANOTHER TRADE SURGE SHOULD BRING BACK A
DRIER REGIME FOR CHUUK...POHNPEI AND MAJURO. CONDITIONS NEAR
KOSRAE CAN REMAIN RELATIVELY WET AS THE TRADE CONVERGENCE ZONE
WILL BE NEARBY.

LATEST ALTIMETRY DATA AND COMPUTER GUIDANCE STRONGLY SUGGEST THE
COMBINATION OF NORTHWEST SWELL...BUILDING TRADE-WIND SWELL AND
WIND WAVES HAS CAUSED SEA HEIGHTS TO REACH HAZARDOUS LEVELS FOR
SMALL CRAFT OPERATION ACROSS CHUUK...POHNPEI STATES AND THE
MARSHALL ISLANDS THIS MORNING. THIS PHENOMENON WILL ALSO OCCUR
NEAR KOSRAE BY MONDAY EVENING AND THEN CONTINUE FOR ALL THE
LOCATIONS THRU MIDWEEK. INTER-ISLAND/ATOLL TRAVEL BY BOAT SHOULD
BE HALTED FOR THE NEXT SEVERAL DAYS.

LARGE EAST-NORTHEAST TRADE-WIND SWELL WILL ALSO CAUSE HAZARDOUS
SURF ON KOSRAE BY LATE THIS AFTERNOON...ACROSS THE MARSHALLS BY
MONDAY AND POSSIBLY FOR POHNPEI AND CHUUK BY TUESDAY. COINCIDED
WITH THE SPRING HIGH TIDE CYCLE THIS WEEK...COASTAL INUNDATION
ARE EXPECTED ON MAJURO AND NEARBY ATOLLS. RESIDENTS ON ALL THE
MENTIONED LOCATIONS NEED TO STAY ALERT ON THE LATEST ADVISORIES
ISSUED BY THE NATIONAL WEATHER SERVICE AND INSTRUCTIONS FROM
THEIR LOCAL EMERGENCY MANAGEMENT OFFICES.

&&

.WESTERN MICRONESIA...
REASONING FOR THE CHUUK FORECAST IS INCLUDED UNDER THE EASTERN
MICRONESIA SECTION ABOVE DUE TO A SIMILAR TRADE-WIND PATTERN.

THE LARGE DOME OF HIGH PRESSURE HAS DRIFTED FARTHER NORTHEAST OF
THE MARIANA ISLANDS. THIS WILL ALLOW TRADE WINDS ACROSS THE
REPUBLIC OF PALAU AND YAP STATE TO BECOME MODERATE AND VEER TO
THE EAST TODAY. AS THE RESULT...A FEW SURFACE IMPULSES EMBEDDED
WITHIN THE TRADE FLOW WILL PASS THRU THE AREA AND GENERATE
SPORADIC CONVECTION NEAR YAP AND KOROR FOR THE NEXT COUPLE DAYS.
BY TUESDAY...ANOTHER HIGH PRESSURE SYSTEM COMING OFF THE EAST
CHINA SEA WILL REINFORCE ANOTHER SURGE OF NORTHEASTERLY WINDS AND
USHER IN PLEASANT BUT BREEZY CONDITIONS. TOWARD THE END OF THIS
WEEK...A BETTER ORGANIZED TRADE DISTURBANCE CURRENTLY UPSTREAM
OVER EASTERN MICRONESIA CAN BRING BACK SHOWERY WEATHER TO BOTH
PLACES.

RESIDUAL NORTH SWELL HAS SUBSIDED ENOUGH ACROSS THE REPUBLIC OF
PALAU AND YAP STATE TO ALLOW SURF TO DROP BELOW HAZARDOUS LEVELS
THIS MORNING. HOWEVER...BUILDING TRADE-WIND SWELL AND WIND WAVES
WILL CAUSE SEAS TO REMAIN HAZARDOUS FOR SMALL CRAFT UNTIL THIS
AFTERNOON. THERE IS A CHANCE THAT SEAS COULD RISE BACK UP AGAIN
LATER THIS WEEK AS TRADE-WIND SWELL BUILDS HIGHER.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...HIGH SURF ADVISORY UNTIL NOON CHST TODAY FOR GUZ001>004.

MARIANAS WATERS...SMALL CRAFT ADVISORY UNTIL 6 AM CHST WEDNESDAY FOR PMZ151>154.

&&

$$

ZIOBRO/CHAN







000
FXPQ60 PGUM 200638
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
438 PM CHST SAT DEC 20 2014

.MARIANAS SYNOPSIS...
FRESH TO STRONG TRADES AND ISOLATED SHOWERS ARE FOUND OVER THE
MARIANAS WATERS. SATELLITE SHOWS A SHEAR LINE ACROSS PAGAN AND
AGRIHAN ISLANDS...BUT NOT MAKING ANY SOUTHWARD PROGRESS. SEAS ARE
RUNNING 9-10 FEET AT THE IPAN BUOY AND NEAR 12 FEET AT RITIDIAN.

&&

.DISCUSSION...
NO IMPORTANT CHANGES WERE MADE TO THE FORECAST. BREEZY CONDITIONS
AND ISOLATED TRADE-WIND SHOWERS WILL PERSIST THE NEXT COUPLE OF
DAYS...POSSIBLY UNTIL TUESDAY IF THE LATEST GFS IS CORRECT.

&&

.MARINE...
BASED ON BUOYS...BOOSTED TOTAL SEAS AND NORTH SWELL A FOOT OR SO
OVERNIGHT AND THROUGH NOON ON SUNDAY. ALSO EXTENDED THE HIGH SURF
ADVISORY THROUGH NOON SUNDAY. OTHERWISE...THE REST OF THE FORECAST
IS THE SAME AS PREVIOUS...WITH 10-FOOT OR HIGHER SEAS AND WINDS
NEAR OR ABOVE 22 KT INTO MID-WEEK.

&&

.EASTERN MICRONESIA...
A FEW SHOWERS DEVELOPED NEAR POHNPEI AND KOSRAE THIS AFTERNOON...
BUT COVERAGE REMAINS GENERALLY ISOLATED WHILE MAJURO REMAINS DRY.
THE LATEST MODEL RUN INDICATES INCREASING SHOWER COVERAGE ACROSS
THE REGION TONIGHT AND SUNDAY WITH SHOWERS MOVING OVER POHNPEI A
BIT EARLIER THAN THE PREVIOUS FORECAST. THE GFS40 DOES NOT
INITIALIZE WELL WITH THE CURRENT PRECIP FOOTPRINT SO CHOSE TO
MAINTAIN THE INHERITED FORECAST WITH ONLY MINOR SHORT TERM
CHANGES. AN INCREASE IN CLOUD COVER AND THE ADDITION OF SLIGHT
CHANCE THUNDER WORDING FOR SUNDAY AT POHNPEI AND REDUCING NEAR
TERM THUNDERSTORM COVERAGE FOR MAJURO FROM ISOLATED TO SLIGHT
CHANCE. OTHERWISE...THE OVERALL FORECAST AND REASONING FOR ALL
THREE FORECAST POINTS REMAINS UNCHANGED.

INCREASING SWELL AND WIND WAVES ARE STILL EXPECTED FROM POHNPEI
TO MAJURO OVER THE NEXT FEW DAYS. THIS WILL RESULT IN INCREASING
RIP CURRENTS AND SURF HEIGHTS...ESPECIALLY ON EASTERN SHORELINES
AND REEFS. SEAS ARE EXPECTED TO BECOME HAZARDOUS FOR SMALL CRAFT
BY MONDAY FOR MAJURO AND POHNPEI AND BY TUESDAY FOR KOSRAE. AS
THE SEAS INCREASE...HAZARDOUS SURF CONDITIONS ARE ALSO EXPECTED
TO DEVELOP SUNDAY OR MONDAY. A HIGH SURF ADVISORY IS LIKELY FOR
ALL THREE FORECAST POINTS EARLY IN THE WEEK AND A HIGH SURF
WARNING IS EVEN A POSSIBILITY FOR MAJURO. AS HIGH SURF CONDITIONS
ARE EXPECTED TO AFFECT MAJURO IN CONJUNCTION WITH THE SPRING HIGH
TIDE CYCLE...COASTAL INUNDATIONS ARE LIKELY ON MAJURO AND NEARBY
ATOLLS. RESIDENTS OF POHNPEI AND KOSRAE SHOULD ALSO REMAIN ALERT
TO THIS DEVELOPING SITUATION OVER THE NEXT FEW DAYS.

&&

.WESTERN MICRONESIA...
FAIRLY DRY CONDITIONS ARE EXPECTED TO CONTINUE ON CHUUK FOR THE
NEXT COUPLE OF DAYS. ON MONDAY...THE TRADE-WIND SURGE AFFECTING
MOST OF EASTERN MICRONESIA IS EXPECTED TO BRING INCREASING
SHOWERS TO CHUUK. SHOWER COVERAGE IS EXPECTED TO REMAIN
ISOLATED...BUT THUNDERSTORMS ARE ALSO EXPECTED ENTER THE PICTURE.
THIS INCREASED CONVECTION WILL STICK AROUND A COUPLE OF
DAYS...WITH FAIR WEATHER RETURNING TO WENO BY MIDWEEK. FOR
YAP...A SERIES OF WEAK TRADE- WIND DISTURBANCES MOVING ACROSS THE
REGION NEAR 8N WILL BRING PERIODS OF SHOWERS TO YAP THROUGH THE
REMAINDER OF THE WEEKEND AND TO KOROR BY SUNDAY EVENING.
MAINTAINED THE INHERITED FORECAST FOR YAP CALLING FOR ISOLATED
SHOWERS AND SLIGHT CHANCE OF THUNDERSTORMS...BUT SHORT PERIODS OF
SCATTERED SHOWERS ARE POSSIBLE THERE TONIGHT AND SUNDAY. STRONG
HIGH PRESSURE CENTERED SOUTH OF JAPAN WILL HELP MAINTAIN FASTER
TRADE WINDS OVER WESTERN MICRONESIA THROUGH THE NEXT FEW
DAYS...THOUGH THE WINDS ARE A BIT LIGHTER TODAY THAN EXPECTED. A
DRIER PATTERN IS EXPECTED TO RETURN TO BOTH LOCATIONS BY MIDWEEK.

HAZARDOUS SURF WILL PERSIST ACROSS THE REPUBLIC OF PALAU AND YAP
STATE THRU TONIGHT AS RESIDUAL NORTH SWELL LINGERS IN THE REGION.
BUILDING TRADE-WIND SWELL AND WIND WAVES WILL HELP SEAS REMAIN
HAZARDOUS FOR SMALL CRAFT UNTIL AT LEAST SUNDAY AFTERNOON.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...HIGH SURF ADVISORY UNTIL NOON CHST SUNDAY FOR GUZ001>004.

MARIANAS WATERS...SMALL CRAFT ADVISORY UNTIL 6 AM CHST WEDNESDAY
     FOR PMZ151>154.

&&

$$

MIDDLEBROOKE/KLEESCHULTE









000
FXPQ60 PGUM 192143
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
743 AM CHST SAT DEC 20 2014

.MARIANAS SYNOPSIS...EAST TRADE-WINDS AND ISOLATED SHOWERS PREVAILED
ACROSS THE MARIANAS THIS MORNING.

&&

.DISCUSSION...
LITTLE CHANGE MADE TO FORECAST. STRONG HIGH PRESSURE BUILDING OUT
INTO THE NORTHWEST PACIFIC WILL KEEP WINDS ELEVATED ACROSS THE
MARIANAS THROUGH TONIGHT. MODELS SHOW THAT WIND SPEEDS MAY
DECREASE SLIGHTLY SUNDAY THROUGH MONDAY NIGHT BUT WILL AGAIN RISE
BY MID-WEEK AS ANOTHER HIGH PRESSURE AREA BUILDS OUT OF ASIA.
MODELS DEPICT A FEW TRADE-WIND DISTURBANCE PASSING ACROSS THE
LOCAL AREA. THIS WILL PRODUCE PERIODS OF CLOUDS AND SHOWERS
THROUGH AT LEAST SUNDAY NIGHT.

&&

.MARINE...
AN EAST TRADE-WIND SWELL AND A NORTH TO NORTHWEST SWELL WILL
PERSIST THROUGH THE FORECAST. RITIDIAN BUOY SHOWS THE NORTHWEST
SWELL AROUND 6 FEET AT 13 SEC THIS MORNING.THIS IS PREDICTED TO
PRODUCE A SURF HEIGHT OF AT LEAST 9 FEET. WENT WITH SURF OF 8 TO
10 FEET ON NORTH FACING REEFS AND 7 TO 9 FEET ON WEST FACING
REEFS THROUGH AT LEAST SUNDAY MORNING. THIS IS ABOVE HAZARDOUS
LEVELS SO ISSUED A HIGH SURF ADVISORY. MODELS SHOW THIS SWELL
DECREASING BY SUNDAY MORNING SO ADVISORY IS ONLY OUT UNTIL SUNDAY
MORNING. RITIDIAN AND IPAN BUOYS SHOW SEA HEIGHTS OF 10 TO 12
FEET. VAD WIND PROFILE SHOWS 2KFT WINDS ABOVE 30 KNOTS.
SCATTEREOMETER DATA SHOWS WINDS OF 20 TO 25 KNOTS OVER THE AREA.
A SMALL CRAFT ADVISORY IS IN EFFECT FOR WINDS AND SEAS THROUGH AT
LEAST WEDNESDAY. ADDED GUST TO 30 KNOTS IN FORECAST BECAUSE OF
THE VAD AND SCATTEROMETER DATA AS WELL AS SURFACE OBS. THERE HAVE
ALREADY BEEN A FEW PEAK WINDS OBSERVED ACROSS THE MARIANAS THIS
MORNING WHICH SEEMS TO VERIFY GUST TO 30 KNOTS.

&&

.EASTERN MICRONESIA...
THE LEADING EDGE OF SURGING NORTHEASTERLY TRADES WILL TRIGGER A
FEW SHOWERS NEAR CHUUK AND POHNPEI TODAY. OTHERWISE...FAIR TRADE
WEATHER IS GOING TO PREVAIL ACROSS CHUUK THRU SUNDAY NIGHT AND
POHNPEI UNTIL SUNDAY EVENING. LATEST ASCAT SATELLITE IMAGERY
INDICATES EVEN STRONGER SURGING TRADES SOUTHEAST OF HAWAII HAVE
DISPLACED THE TRADE CONVERGENCE ZONE SOUTHWARD TO SOUTH OF 5N. ON
THE OTHER HAND...THESE TRADES HAVE ENHANCED A DISTURBANCE
APPROACHING THE MARSHALL ISLANDS THIS MORNING. SOUNDING DATA FROM
WSO MAJURO LAST NIGHT REVEALS STRONG VERTICAL WIND SHEAR OF 15 TO
25 KT BETWEEN 500 AND 350MB... CAUSED BY THE ADVANCING ELEMENT OF
THE SAME SURGING TRADES ALOFT. THIS HAS PREVENTED CONVECTION TO
MATERIALIZE NEAR MAJURO LAST NIGHT DESPITE THE PRESENCE OF A
DISTURBANCE. AS TRADES INCREASE NEAR THE SURFACE TODAY...VERTICAL
WIND SHEAR WILL DIMINISH WHICH SHOULD ALLOW CONVECTION TO FLARE
UP NEAR MAJURO. THIS DISTURBANCE IS GOING TO GRADUALLY PROGRESS
WESTWARD AND AFFECT KOSRAE BY SUNDAY MORNING. IT COULD EVENTUALLY
REACH POHNPEI AND CHUUK AROUND MONDAY. A FEW MORE DISTURBANCES
CAN ALSO BE SEEN UPSTREAM EAST OF THE DATE LINE. THESE SYSTEMS
WILL PROBABLY PROLONG OFF AND ON SHOWERS FOR MAJURO THRU
MONDAY...KOSRAE...POHNPEI AND CHUUK UNTIL MIDWEEK. AS THE LARGE
DOME OF HIGH PRESSURE CURRENTLY SOUTH OF JAPAN DRIFTS EASTWARD
OVER THE NEXT FEW DAYS...IT WILL CROSS THE DATE LINE BY EARLY
NEXT WEEK. IN RESPONSE...A THIRD WAVE OF SURGING TRADES IS
SCHEDULED TO ARRIVE AT THE MARSHALLS. THESE DRIER TRADES MIGHT BE
ABLE TO USHER IN NICER WEATHER FOR MAJURO.

NORTHWEST SWELL PRODUCED BY STRONG WINDS BEHIND THE COLD FRONT TO
THE NORTH ALONG WITH LARGE TRADE-WIND SWELL AND WIND WAVES WILL
CAUSE SEAS TO RISE FROM CHUUK STATE EASTWARD TO THE MARSHALL
ISLANDS OVER THE NEXT FEW DAYS. THEREFORE...SEAS WILL BECOME
HAZARDOUS FOR SMALL CRAFT NEAR KOSRAE BY TUESDAY AND THE REST OF
THE LOCATIONS BY MONDAY. TRADE-WIND SWELL WILL ALSO CAUSE
HAZARDOUS SURF FOR ALL THE LOCATIONS AS WELL. IN CONJUNCTION WITH
THE SPRING HIGH TIDE CYCLE STARTING MONDAY...COASTAL INUNDATIONS
ARE LIKELY ON MAJURO AND NEARBY ATOLLS. RESIDENTS OF CHUUK STATE
EASTWARD TO THE MARSHALL ISLANDS WILL NEED TO STAY ALERT ON THIS
DEVELOPING SITUATION OVER THE NEXT SEVERAL DAYS.

&&

.WESTERN MICRONESIA...
REASONING FOR THE CHUUK FORECAST IS INCLUDED UNDER THE EASTERN
MICRONESIA SECTION ABOVE DUE TO A SIMILAR TRADE-WIND PATTERN.

A STRONG HIGH PRESSURE SYSTEM SLIDING EASTWARD FROM SOUTH OF
JAPAN WILL DIRECT FRESH TO STRONG TRADE WINDS TOWARD THE REPUBLIC
OF PALAU AND YAP STATE FOR THE NEXT SEVERAL DAYS. A SERIES OF
TRADE-WIND DISTURBANCES CAN BE SEEN UPSTREAM ALONG
8N...STRETCHING EASTWARD FROM 140E TO 170E. EXPECT THESE
DISTURBANCES TO BRING PERIODIC SHOWERS AND EVEN A THUNDERSTORM OR
TWO TO YAP THRU MONDAY...AND TO KOROR BY SUNDAY EVENING. TOWARD
MIDWEEK...A STRENGTHENING UPPER-LEVEL HIGH OVER THE PHILIPPINE
SEA COULD PROVIDE ENOUGH SUBSIDENCE TO INTRODUCE A DRIER PATTERN
FOR BOTH PLACES.

HAZARDOUS SURF WILL PERSIST ACROSS THE REPUBLIC OF PALAU AND YAP
STATE THRU TONIGHT AS RESIDUAL NORTH SWELL LINGERS IN THE REGION.
COMBINING WITH BUILDING TRADE-WIND SWELL AND WIND WAVES...SEAS
WILL ALSO REMAIN HAZARDOUS FOR SMALL CRAFT UNTIL AT LEAST SUNDAY
AFTERNOON.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...HIGH SURF ADVISORY UNTIL 6 AM CHST SUNDAY FOR GUZ001>004.

MARIANAS WATERS...SMALL CRAFT ADVISORY UNTIL 6 AM CHST WEDNESDAY FOR PMZ151>154.

&&

$$

ZIOBRO/CHAN







000
FXPQ60 PGUM 190715
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
515 PM CHST FRI DEC 19 2014

.MARIANAS SYNOPSIS...
A ROBUST SHEAR LINE STRETCHES SOUTHWESTWARD OVER THE FAR NORTHERN
MARIANAS. A CLUSTER OF SHOWERS IS PASSING THROUGH GUAM WATERS BUT
THE HEAVIEST CONVECTION REMAINS SOUTH OF GUAM WATERS. RADAR WIND
PROFILE SHOWS 30 TO 35 KT NORTHEAST WINDS FROM 2000 TO 5000 FEET
WHILE SURFACE OBSERVATIONS SHOW 20 KT WITH GUSTS TO 30 KT ACROSS
THE REGION.

&&

.DISCUSSION...
FRESH TO STRONG NORTHEAST WINDS WILL PREVAIL THROUGH SATURDAY
BEFORE DIMINISHING SOMEWHAT LATE SATURDAY. MAINLY DRY CONDITIONS
ARE EXPECTED FOR THE NEXT SEVERAL DAYS AS THE SHEAR LINE STALLS
ACROSS THE FAR NORTHERN MARIANAS OVER THE WEEKEND. WINDS WILL
DECREASE A BIT SATURDAY NIGHT BUT WILL REMAIN FRESH THROUGH THE
NEXT FEW DAYS. A SECONDARY TRADE-WIND SURGE WILL INCREASE WINDS
ONCE AGAIN BY THE MIDDLE OF NEXT WEEK BUT NO MAJOR WEATHER
SYSTEMS ARE EXPECTED TO AFFECT THE MARIANAS.

&&

.MARINE...
RITIDIAN BUOY SHOWS SEAS HAVE RISEN STEADILY TODAY TO AROUND 11
FEET. A SMALL CRAFT ADVISORY REMAINS IN EFFECT AT LEAST THROUGH
WED MORNING. MOST OF THE WAVE ENERGY IS WIND WAVES BUT PERSISTENT
FRESH TO STRONG TRADE WINDS WILL CONTINUE TO BUILD A SIGNIFICANT
ENE SWELL OVER THE NEXT 36 HOURS. THIS WILL BRING SURF ON EAST
FACING SHORES VERY CLOSE TO HAZARDOUS LEVELS BY SATURDAY MORNING.
A HIGH SURF ADVISORY ISSUANCE WILL LIKELY BE NEEDED OVERNIGHT FOR
EAST FACING REEFS.

&&

.AVIATION...
WIND SHEAR COULD BE AN ISSUE OVERNIGHT ON GUAM IF SIGNIFICANT
DECOUPLING OF THE PBL OCCURS. WINDS AT THE SURFACE WOULD HAVE TO
DECREASE TO BETWEEN 10 AND 15 KNOTS FOR WIND SHEAR TO BECOME AN
ISSUE.

&&

.EASTERN MICRONESIA...
SATELLITE SHOWS SHOWERS ASSOCIATED WITH A TRADE-WIND DISTURBANCE
MOVING WESTWARD ACROSS THE DATE LINE TOWARD MAJURO AND THE TARAWA
AND BUTARITARI AREAS. A WEAK CIRCULATION NEAR 2N169E IS CAUSING
SHOWERS IN A SMALL AREA SOUTHEAST OF KOSRAE. MODELS INDICATE THE
CIRCULATION AND THE DISTURBANCE WILL MOVE WESTWARD IN THE COMING
DAYS WITH SHOWERS FOCUSED MAINLY BETWEEN 3N TO 7N. MODERATE TO
FRESH TRADE WINDS ARE DEVELOPING FOR EASTERN MICRONESIA AND
RELATIVELY WET WEATHER IS EXPECTED TO SPREAD WESTWARD...
ESPECIALLY TOWARD KOSRAE. THE HEAVIER SHOWER ACTIVITY COULD
REMAIN SOUTH OF MAJURO AND POHNPEI IF MODEL SOLUTIONS ARE
CORRECT.

RELATIVELY DRY WEATHER IS EXPECTED AT CHUUK NEXT COUPLE DAYS...
THEN SOME CLOUDINESS AND SHOWERS COULD SPREAD TOWARD CHUUK FROM
EASTERN MICRONESIA EARLY NEXT WEEK.

NORTHWEST SWELL PRODUCED BY STRONG WINDS OVER THE NORTHWEST
PACIFIC ALONG WITH LARGE TRADE-WIND SWELL AND WIND WAVES WILL
CAUSE SEA CONDITIONS TO RISE FROM CHUUK STATE EASTWARD TO THE
MARSHALL ISLANDS OVER THE NEXT FEW DAYS. CONDITIONS COULD
POSSIBLY BECOME HAZARDOUS FOR SMALL CRAFT BY SUNDAY OR MONDAY.
TRADE-WIND WAVES MAY ALSO CAUSE HAZARDOUS SURF FOR KOSRAE AND THE
MARSHALLS AS WELL. AND...WITH SPRING HIGH TIDE CYCLE STARTING
MONDAY...COASTAL INUNDATIONS ARE LIKELY ON MAJURO AND NEARBY
ATOLLS.

&&

.WESTERN MICRONESIA...
REASONING FOR THE CHUUK FORECAST IS INCLUDED UNDER THE EASTERN
MICRONESIA SECTION ABOVE DUE TO A SIMILAR TRADE-WIND PATTERN.

MODELS INDICATE A PERIOD OF MODERATE TO FRESH TRADE WINDS CAN BE
EXPECTED ACROSS WESTERN MICRONESIA. WEATHER THERE WILL BE
RELATIVELY UNSETTLED EVEN THROUGH THE LONGER TERM. SATELLITE
SHOWS SCATTERED SHOWERS AND A FEW THUNDERSTORMS SOUTH OF GUAM
BETWEEN 10N AND 12N THAT ARE MOVING WESTWARD. THE SHOWERS COULD
AFFECT YAP THE NEXT DAY OR TWO. SATELLITE ALSO SHOWS PATCHY
CLOUDS AND A FEW SHOWERS JUST WEST AND SOUTHEAST OF KOROR. MODELS
INDICATE THAT A LITTLE DRIER WEATHER WILL DEVELOP FOR KOROR THIS
WEEKEND...BUT SURGING TRADES FROM EASTERN MICRONESIA COULD
INCREASE THE CHANCE OF SHOWERS FOR BOTH YAP AND KOROR NEXT WEEK.

HAZARDOUS SURF WILL PERSIST ACROSS THE REPUBLIC OF PALAU AND YAP
STATE THRU SATURDAY EVENING AS NORTH SWELLS PRODUCED BY GALE
FORCE WINDS OVER THE NW PACIFIC CONTINUE TO AFFECT THE REGION. AS
NW SWELL COMBINE WITH TRADE-WIND SWELLS AND WIND WAVES...SEAS
WILL ALSO REMAIN HAZARDOUS FOR SMALL CRAFT UNTIL SUNDAY.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...SMALL CRAFT ADVISORY UNTIL 6 AM CHST WEDNESDAY
                  FOR PMZ151>154.

&&

$$

WILLIAMS/SIMPSON







000
FXPQ60 PGUM 182010
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
610 AM CHST FRI DEC 19 2014

.MARIANAS SYNOPSIS...
SATELLITE SHOWS A SHEARLINE ORIENTED SW-NE ACROSS AGRIHAN...AND A
CLUSTER OF DEEP CONVECTION 155-200 MILES SE OF GUAM. IN BETWEEN
THESE FEATURES...FRESH NORTHEAST TRADES AND ISOLATED SHOWERS ARE
PRESENT IN THE MARIANAS WATERS. WINDS ARE ALREADY ABOVE 25 KT ON
THE RADAR WIND PROFILE. THE BUOYS ARE REPORTING SEAS NEAR 7 FEET.

&&

.DISCUSSION...
WINDS ARE INCREASING AS THE EXPECTED TRADE-WIND SURGE ARRIVES IN THE
REGION...AND BREEZY CONDITIONS WITH WINDS OF 15 TO 25 MPH SHOULD
SET IN THIS MORNING AND LAST THE NEXT FEW DAYS. CLOUDS AND SHOWERS
WILL INCREASE SOMEWHAT...BUT SHOWERS SHOULD STILL BE ISOLATED FOR
THE MOST PART.

IN THE NEAR TERM...SHOWERS CURRENTLY SOUTHEAST OF GUAM ARE SHOWN
IN BOTH THE GFS AND ECMWF. BUT BOTH MODELS KEEP THE RAIN SOUTH OF
GUAM...THOUGH GFS BRINGS THE NORTHERN EDGE PRETTY CLOSE. THIS WILL
BEAR WATCHING AS THE MORNING WEARS ON.

&&

.MARINE/SURF...
HAVE ISSUED A SMALL CRAFT ADVISORY FOR THE NEXT FEW DAYS...AS
WINDS WILL RISE TO 20-25 KT TODAY WITH SEAS NEARING 8 TO 10 FEET
BY AFTERNOON. THE FRESH TO STRONG TRADES SHOULD LAST THROUGH AT
LEAST TUESDAY...WITH A BRIEF BREAK ON MONDAY. SEAS WILL BUILD TO
9-11 FT SATURDAY AND REMAIN IN THAT RANGE THROUGH AT LEAST TUESDAY
AND POSSIBLY ALL THE WAY TO CHRISTMAS DAY.

AT PRESENT...SURF IS EXPECTED TO REMAIN JUST BELOW HAZARDOUS LIMITS.
BUT ANY INCREASE IN THE NORTHWEST TO NORTH SWELL ABOVE THE CURRENTLY
FORECAST 5 FEET COULD PRODUCE HIGH SURF OVER THE WEEKEND OR EARLY
NEXT WEEK ALONG NORTH AND WEST FACING SHORES. HIGH SURF COULD ALSO
OCCUR ALONG EAST FACING REEFS IF WINDS TURN OUT TO BE A LITTLE
STRONGER THAN FORECAST.

&&

.EASTERN MICRONESIA...
THE LEADING EDGE OF ANOTHER TRADE-WIND SURGE IS VISIBLE ON IR
SATELLITE IMAGERY AS A LINE OF SPOTTY SHOWERS NORTHEAST OF POHNPEI
AND NORTH OF KOSRAE THIS MORNING. THIS FEATURE COULD BRING A FEW
PASSING SHOWERS TO KOSRAE AND POHNPEI TONIGHT...AND CHUUK ON
SATURDAY. OTHERWISE...MID AND UPPER-LEVEL DRYNESS SHOULD MAINTAIN
FAIR WEATHER FOR KOSRAE THRU THIS EVENING...POHNPEI AND CHUUK UNTIL
AT LEAST SUNDAY. A TRADE CONVERGENCE ZONE IS ALSO VISIBLE BETWEEN 3N
AND 7N...MEANDERING EASTWARD FROM 175E THRU THE DATE LINE TO BEYOND
155W. AS THIS BOUNDARY INCHES WESTWARD TOWARD THE MARSHALL ISLANDS
THIS EVENING...THE THREAT OF SHOWERS AND THUNDERSTORMS NEAR MAJURO
WILL INCREASE THRU SATURDAY. AS IT CONTINUES TO EXTEND WESTWARD...A
SIMILAR THREAT WILL REACH KOSRAE BY SATURDAY NIGHT. AN EVEN STRONGER
TRADE SURGE IS CURRENTLY PROGRESSING SOUTH OF HAWAII AND WILL MOVE
INTO EASTERN MICRONESIA AROUND SUNDAY. THIS SHOULD NUDGE THE
CONVERGENCE ZONE SOUTH OF 6N WHICH WILL BRING DRIER TRADE WEATHER
BACK TO MAJURO AND PREVENT CONVECTION FROM SPREADING OVER POHNPEI
AND CHUUK. ON THE OTHER HAND...CONVECTION WILL REMAIN NEAR KOSRAE
FOR THE FIRST HALF OF NEXT WEEK. THE CHANCE FOR TRADE-WIND SHOWERS
WILL INCREASE ACROSS POHNPEI AND CHUUK NEXT WEEK AS MOISTURE CREEPS
UP AT MID AND UPPER LEVELS.

SEAS FROM CHUUK STATE EASTWARD TO THE MARSHALL ISLANDS ARE GOING TO
RISE STEADILY OVER THE NEXT FEW DAYS AND POSSIBLY BECOME HAZARDOUS
FOR SMALL CRAFT BY SUNDAY OR MONDAY. THIS WILL BE CONTRIBUTED TO BY
NORTHWEST SWELL PRODUCED BY STRONG WINDS NORTH OF A COLD FRONT AND
LARGE TRADE-WIND SWELL AND WIND WAVES. THIS TRADE-WIND SWELL AND
WIND WAVES COULD CAUSE HAZARDOUS SURF FOR KOSRAE AND THE MARSHALLS
AS WELL. WITH THE SPRING HIGH TIDE CYCLE STARTING MONDAY...COASTAL
INUNDATIONS ARE LIKELY ON MAJURO AND NEARBY ATOLLS.

&&

.WESTERN MICRONESIA...
REASONING FOR THE CHUUK FORECAST IS INCLUDED UNDER THE EASTERN
MICRONESIA SECTION ABOVE DUE TO A SIMILAR TRADE-WIND PATTERN.

LATEST SOUNDING DATA FROM WSO YAP AND WV SATELLITE LOOP INDICATE
SUBSIDENT AIR ABOVE 700MB OVER YAP THIS MORNING. THIS AIR MASS WILL
INTRODUCE A FAIR TRADE REGIME TO YAP TODAY AND KOROR BY THIS EVENING.
A TRADE DISTURBANCE CAN BE SEEN UPSTREAM SOUTHEAST OF GUAM AT 10N148E.
THIS SYSTEM ALONG WITH THE LEADING EDGE OF SURGING TRADES FROM
EASTERN MICRONESIA COULD HEIGHTEN THE CHANCE OF SHOWERS FOR BOTH
LOCALES BY EARLY NEXT WEEK.

HAZARDOUS SURF WILL PERSIST ACROSS THE REPUBLIC OF PALAU AND YAP
STATE THRU SATURDAY EVENING AS NORTH SWELL PRODUCED BY GALE FORCE
WINDS BEHIND A OLD COLD FRONT CONTINUE TO AFFECT THE REGION.
COMBINING WITH TRADE-WIND SWELLS AND WIND WAVES...SEAS WILL ALSO
REMAIN HAZARDOUS FOR SMALL CRAFT UNTIL SUNDAY.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...SMALL CRAFT ADVISORY UNTIL 6 AM CHST WEDNESDAY FOR
     PMZ151>154.

&&

$$

MIDDLEBROOKE/CHAN








    US Dept of Commerce
    National Oceanic and Atmospheric Administration
    National Weather Service
    1325 East West Highway
    Silver Spring, MD 20910
    Page Author: NWS Internet Services Team
Disclaimer
Information Quality
Credits
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities