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000
FXPQ60 PGUM 160808 AAA
AFDPQ

AREA FORECAST DISCUSSION...ADDED MICRONESIAN DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
600 PM CHST TUE SEP 16 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
MOVING THROUGH THE MARIANAS WATERS. THESE SHOWERS ARE ASSOCIATED
WITH A CIRCULATION NEAR YAP...SOUTHWEST OF THE MARIANAS COASTAL
WATERS.

&&

.DISCUSSION...
CONVERGING LOW-LEVEL WINDS NORTHEAST OF THE CIRCULATION NEAR YAP
ARE CREATING SCATTERED SHOWERS AND A FEW THUNDERSTORMS OVER THE
MARIANAS WATERS. THESE SHOULD EASILY CONTINUE TONIGHT...THEN
DIMINISH WEDNESDAY. SEA HEIGHTS WILL GRADUALLY DECREASE ALSO. ONLY
CHANGES MADE TO THE GRIDS WERE TO RAISE THE POP TO 50 AND BUMP THE
CLOUDS UP TO 90 PERCENT CLOUD COVER. THE GENERAL PHILOSOPHY WAS
RIGHT ON. GFS40 IS STILL TRYING TO CLEAR THE SKIES SOMEWHAT NEAR
THE END OF THE FORECAST. IT HAS BEEN TRYING TO DO THIS FOR AT
LEAST A FEW DAYS. IT WILL HAPPEN AT SOME POINT...THE QUESTION IS
WHEN AND THIS REPRESENTS ONE OF THE MAIN FORECAST PROBLEMS. IF
ENOUGH HEAVY SHOWERS TRAIN OVER SPOTS...THERE COULD ALSO BE SOME
LOCALIZED URBAN AND SMALL STREAM FLOODING.

&&

.EASTERN MICRONESIA...
A SURFACE TROUGH EXTENDS NORTHEASTWARD SOUTH OF KOSRAE TO EAST OF
MAJURO TO NEAR THE DATE LINE AT 11N. THE TROUGH IS MOVING WESTWARD
AND WEATHER ASSOCIATED WITH THE TROUGH SHOULD REACH KOSRAE WEDNESDAY
NIGHT. MEANWHILE...SHOWERS ASSOCIATED WITH A CONVERGENCE ZONE ARE
CROSSING THE DATE LINE AND WILL REACH MAJURO TONIGHT. MODELS PROG
RELATIVELY DRY CONDITIONS AROUND THURSDAY FOR THE FORECAST ZONES.
LATER IN THE WEEK MODELS SHOW A CONVERGENT PATTERN SETTING UP THAT
COULD BRING MORE MOISTURE BY THE WEEKEND TO THE MARSHALL ISLANDS AND
KOSRAE. THE MENTION OF THUNDERSTORMS ARE INCLUDED IN THE MAJURO AND
POHNPEI FORECASTS FOR TONIGHT BECAUSE THEIR SOUNDINGS INDICATE
CONDITIONS CONDUCIVE FOR THE POSSIBILITY OF THUNDERSTORMS.

&&

.WESTERN MICRONESIA...
DRY WEATHER IS SEEN AT CHUUK THIS EVENING WITH SURFACE RIDGING
WEDGED IN ACROSS THE STATE. DRY WEATHER WILL PERSIST THROUGH
TONIGHT. UNSETTLED WEATHER WILL DEVELOP ACROSS THE STATE AHEAD OF A
SURFACE TROUGH APPROACHING FROM THE EAST. DRIER WEATHER WILL RETURN
FOR THE END OF THE WEEK. FORECAST REMAINS QUESTIONABLE IN THE LONG
TERM AS MODELS DIVERGE.

AT KOROR AND YAP...A BROAD CIRCULATION CENTERED NEAR YAP NEAR
10N139E REMAINS THE MAIN WEATHER FEATURE. ISOLATED TO SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS REMAIN AT BOTH LOCATIONS THIS
EVENING. MODELS STILL DEPICT A WET PATTERN THROUGH TONIGHT FOR BOTH
LOCATIONS...BUT LATE AFTERNOON STABILITY HAS TEMPERED THE CONVECTION
FOR THE TIME BEING ESPECIALLY AT YAP. STRONGER SOUTHWEST WINDS WILL
BUILD IN BEHIND THE DISTURBANCE AS IT CONTINUES TOWARDS THE
WEST-NORTHWEST ON WEDNESDAY. RIDGING WILL USHER IN DRIER WEATHER FOR
THE END OF THE WEEK.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...NONE.
&&

$$

STANKO/DEVITA










000
FXPQ60 PGUM 160614
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
414 PM CHST TUE SEP 16 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
MOVING THROUGH THE MARIANAS WATERS. THESE SHOWERS ARE ASSOCIATED
WITH A CIRCULATION NEAR YAP...SOUTHWEST OF THE MARIANAS COASTAL
WATERS.

&&

.DISCUSSION...
CONVERGING LOW-LEVEL WINDS NORTHEAST OF THE CIRCULATION NEAR YAP
ARE CREATING SCATTERED SHOWERS AND A FEW THUNDERSTORMS OVER THE
MARIANAS WATERS. THESE SHOULD EASILY CONTINUE TONIGHT...THEN
DIMINISH WEDNESDAY. SEA HEIGHTS WILL GRADUALLY DECREASE ALSO. ONLY
CHANGES MADE TO THE GRIDS WERE TO RAISE THE POP TO 50 AND BUMP THE
CLOUDS UP TO 90 PERCENT CLOUD COVER. THE GENERAL PHILOSOPHY WAS
RIGHT ON. GFS40 IS STILL TRYING TO CLEAR THE SKIES SOMEWHAT NEAR
THE END OF THE FORECAST. IT HAS BEEN TRYING TO DO THIS FOR AT
LEAST A FEW DAYS. IT WILL HAPPEN AT SOME POINT...THE QUESTION IS
WHEN AND THIS REPRESENTS ONE OF THE MAIN FORECAST PROBLEMS. IF
ENOUGH HEAVY SHOWERS TRAIN OVER SPOTS...THERE COULD ALSO BE SOME
LOCALIZED URBAN AND SMALL STREAM FLOODING.

&&

.EASTERN MICRONESIA...
WILL BE ADDED AFTER 5 PM.

&&

.WESTERN MICRONESIA...
WILL BE ADDED AFTER 5 PM.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...NONE.
&&

$$

STANKO/DEVITA







000
FXPQ60 PGUM 151933
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
533 AM CHST TUE SEP 16 2014

.MARIANAS SYNOPSIS...
RADAR SHOWS WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
OVER THE EAST AND SOUTHEAST PARTS OF THE COVERAGE AREA WITH LARGER
AREAS OF RAIN NORTHWEST OF GUAM. SATELLITE IR SHOWS SEVERAL AREAS
OF CLOUDS AND SHOWERS EAST OF THE MARIANAS TO BEYOND 155E. ASCAT
ANALYSIS INDICATES THE WEAK CIRCULATION ASSOCIATED WITH INVEST
AREA 96W WAS NEAR 11N141E AND DRIFTING WESTWARD. VAD GRADIENT
WINDS ARE SE 15-20 KT. BUOYS SHOW COMBINED SEAS OF 4 TO 5 FEET
WITH DIRECTIONAL COMPONENTS FROM WEST AND EAST-NORTHEAST.

&&

.DISCUSSION...
MODELS INDICATE WET MONSOON-TYPE WEATHER WILL CONTINUE THE NEXT
COUPLE DAYS WHILE INVEST AREA 96W GRADUALLY DEVELOPS AND DRIFTS
WESTWARD AND THEN NORTHWESTWARD. ONLY MINOR CHANGES WERE MADE TO
THE PUBLIC FORECAST AT THIS TIME.

&&

.MARINE...
MIXED SEA CONDITIONS ARE EXPECTED THIS WEEK. ADJUSTMENTS WERE MADE
TO WAVE GRIDS BASED ON WW3 MODEL WHICH INDICATES SEVERAL DIFFERENT
SMALLISH SWELL COMPONENTS COULD AFFECT SEA CONDITIONS BESIDES THE
BASIC EAST AND WEST SWELLS ALREADY IN THE FORECAST. NOTHING BIG IS
IN THE FORECAST BUT SUBTLE CHANGES TO SEA CONDITIONS WILL NEED TO BE
MONITORED. REFRESHED WIND GRIDS WITH LATEST GFS MODEL DATA.

&&

.EASTERN MICRONESIA...
LATEST MODEL RUNS INITIALIZE REASONABLY WELL WITH IR SATELLITE
IMAGERY AND 12Z ASCAT ANALYSIS. A SURFACE TROUGH STRETCHES FROM
NEAR POHNPEI...OVER KOSRAE AND MAJURO TO NEAR THE DATE LINE AT 11N.
SHOWER COVERAGE HAS DECREASED ALONG THE TROUGH SO SHOWERS WERE
REDUCED TO ISOLATED TODAY AT MAJURO...BUT MAINTAINED ISOLATED
THUNDERSTORMS. ISOLATED THUNDERSTORMS WERE ADDED TO KOSRAE AND
POHNPEI WITH THEIR PROXIMITY TO THE TROUGH. MORE SHOWERS ARE
CROSSING THE DATE LINE EAST OF THE TROUGH AND WILL REACH MAJURO
TONIGHT. MODELS PROG DRIER WEATHER FOR LATE WEDNESDAY AND THURSDAY
ACROSS THE REGION. LATER IN THE WEEK MODELS SHOW A CONVERGENT
PATTERN SETTING UP THAT COULD BRING MORE MOISTURE BY THE WEEKEND
TO THE MARSHALL ISLANDS AND KOSRAE.

&&

.WESTERN MICRONESIA...
DRY WEATHER IS SEEN AT CHUUK THIS MORNING WITH SURFACE RIDGING
WEDGED IN ACROSS THE STATE. DRY WEATHER WILL PERSIST THROUGH
TONIGHT. UNSETTLED WEATHER WILL DEVELOP ACROSS THE STATE AHEAD OF
A SURFACE TROUGH APPROACHING FROM THE EAST. DRIER WEATHER WILL
RETURN FOR THE END OF THE WEEK. FORECAST IS QUESTIONABLE IN THE
LONG TERM AS MODELS SHOW A CONVERGENT LIGHT AND VARIABLE WIND
PATTERN FRIDAY AND SATURDAY IN EASTERN MICRONESIA. MODELS FOR NOW
KEEP ASSOCIATED WEATHER NEAR AND EAST OF POHNPEI.

AT KOROR AND YAP...A BROAD CIRCULATION CENTERED NEAR YAP AT
11N139E THIS MORNING REMAINS THE MAIN WEATHER FEATURE. SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS HAVE REACHED BOTH LOCATIONS
THIS MORNING. MODELS STILL DEPICT A WET PATTERN AT LEAST THROUGH
TONIGHT FOR BOTH LOCATIONS. STRONGER SOUTHWEST WINDS WILL BUILD IN
BEHIND THE DISTURBANCE AS IT CONTINUES TOWARDS THE WEST-NORTHWEST
ON WEDNESDAY. RIDGING WILL USHER IN DRIER WEATHER FOR THE END OF
THE WEEK.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...NONE.

&&

$$

SIMPSON/M. AYDLETT








000
FXPQ60 PGUM 151804
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
404 AM CHST TUE SEP 16 2014

.MARIANAS SYNOPSIS...
RADAR SHOWS WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
OVER THE EAST AND SOUTHEAST PARTS OF THE COVERAGE AREA WITH LARGER
AREAS OF RAIN NORTHWEST OF GUAM. SATELLITE IR SHOWS SEVERAL AREAS
OF CLOUDS AND SHOWERS EAST OF THE MARIANAS TO BEYOND 155E. ASCAT
ANALYSIS INDICATES THE WEAK CIRCULATION ASSOCIATED WITH INVEST
AREA 96W WAS NEAR 11N141E AND DRIFTING WESTWARD. VAD GRADIENT
WINDS ARE SE 15-20 KT. BUOYS SHOW COMBINED SEAS OF 4 TO 5 FEET
WITH DIRECTIONAL COMPONENTS FROM WEST AND EAST-NORTHEAST.

&&

.DISCUSSION...
MODELS INDICATE WET MONSOON-TYPE WEATHER WILL CONTINUE THE NEXT
COUPLE DAYS WHILE INVEST AREA 96W GRADUALLY DEVELOPS AND DRIFTS
WESTWARD AND THEN NORTHWESTWARD. ONLY MINOR CHANGES WERE MADE TO
THE PUBLIC FORECAST AT THIS TIME.

&&

.MARINE...
MIXED SEA CONDITIONS ARE EXPECTED THIS WEEK. ADJUSTMENTS WERE MADE
TO WAVE GRIDS BASED ON WW3 MODEL WHICH INDICATES SEVERAL DIFFERENT
SMALLISH SWELL COMPONENTS COULD AFFECT SEA CONDITIONS BESIDES THE
BASIC EAST AND WEST SWELLS ALREADY IN THE FORECAST. NOTHING BIG IS
IN THE FORECAST BUT SUBTLE CHANGES TO SEA CONDITIONS WILL NEED TO BE
MONITORED. REFRESHED WIND GRIDS WITH LATEST GFS MODEL DATA.

&&

.EASTERN MICRONESIA...WILL BE SENT LATER.

&&

.WESTERN MICRONESIA...WILL BE SENT LATER.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...NONE.
&&

$$

SIMPSON






000
FXPQ60 PGUM 150649
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
449 PM CHST MON SEP 15 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS ANOTHER ROUND OF SCATTERED SHOWERS STARTING TO
DEVELOP EAST OF THE MARIANAS WATERS. THE VAD WIND PROFILE REVEALS
SOUTHEAST WINDS OF 10 TO 15 KNOTS THROUGH THE LOWEST 10 THOUSAND
FEET OF THE AIR.

&&

.DISCUSSION...
MONSOON TROUGH RUNS JUST SOUTH OF GUAM WATERS WITH A TROPICAL
DISTURBANCE SLIDING TOWARD THE WEST ALONG IT. THIS IS KEEPING THE
SHOWERS A LITTLE MORE ACTIVE THAN USUAL. UPPER-LEVEL TROUGHING IS
FURTHER ENHANCING THE DYNAMICS AND ALLOWING ISOLATED THUNDERSTORM
CELLS TO DEVELOP. WENT AHEAD AND EXTENDED MOSTLY CLOUDY BY A
COUPLE OF DAYS AND TWEAKED THE HIGH TEMPERATURES ACCORDINGLY.
LATELY WE HAVE BEEN A BIT TOO OPTOMISTIC IN THE EXTENDED
FORECAST.

EAST AND WEST SWELLS ARE NOT THAT IMPRESSIVE
SEPARATELY...TOGETHER THOUGH THEY ADD UP TO BETWEEN 4 AND 6 FEET
COMBINED SEAS. THESE SEAS WILL PERSIST THROUGH ABOUT WEDNESDAY
THEN START TO GRADUALLY DECLINE FOR THE SECOND HALF OF THE
WEEK...LEADING TO BENIGN MARINE CONDITIONS.

&&

.EASTERN MICRONESIA...
A SURFACE TROUGH STRETCHED ACROSS EASTERN MICRONESIA THIS
AFTERNOON. SURFACE CONVERGENCE SOUTH OF THE TROUGH PRODUCED AN
AREA OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS SOUTH AND
EAST OF MAJURO. THIS AREA WILL EXPAND AND PUSH ACROSS MAJURO
LATER TONIGHT AND PERSIST ACROSS MAJURO THROUGH MUCH OF TUESDAY.
EXPECT ISOLATED THUNDERSTORMS THERE TONIGHT THROUGH TUESDAY
NIGHT.

ANOTHER AREA OF SURFACE CONVERGENCE SOUTH OF THE TROUGH WILL
BRING MOSTLY CLOUDY SKIES AND A CHANCE OF THUNDERSTORMS TO
POHNPEI AND KOSRAE TONIGHT.

PART OF THE TROUGH WILL MOVE WEST BECOMING LOCATED BETWEEN
POHNPEI AND KOSRAE TUESDAY. THIS WILL CAUSE WINDS TO BE NORTHEAST
AT POHNPEI AND SOUTHEAST AT KOSRAE. LITTLE MOISTURE IS ASSOCIATED
WITH THIS PART OF THE TROUGH AND SO SHOWERS WILL REMAIN ISOLATED
AT THESE TWO LOCATIONS. THIS TROUGH WILL MOVE VERY SLOWLY WEST
LOCATING ITSELF WEST OF POHNPEI THURSDAY. MODELS SHOW IT ARCHING
BACK ACROSS EASTERN MICRONESIA NORTH OF POHNPEI AND KOSRAE
FRIDAY.

MODELS HINT AT A CIRCULATION DEVELOPING ON THIS TROUGH NORTH OF
KOSRAE BY FRIDAY. A FEW MODELS DEPICT SCATTERED SHOWERS ACROSS
PARTS OF EASTERN MICRONESIA FRIDAY AND SATURDAY. CONFIDENCE IN
THIS IS LOW SO WILL LEAVE SHOWERS ISOLATED IN FORECAST FOR THE
THREE FORECAST LOCATIONS FOR NOW.

&&

.WESTERN MICRONESIA...
THE MONSOON TROUGH STRETCHED ACROSS THE WESTERN PACIFIC THIS
AFTERNOON TO A CIRCULATION LOCATED JUST SOUTHEAST OF GUAM AND
CONTINUED EASTWARD FAR TO THE NORTH OF CHUUK. CONVERGENCE SOUTH
OF THE TROUGH WILL BRING ISOLATED THUNDERSTORMS TO PALAU AND
SCATTERED SHOWERS AND ISOLATED THUNDERSTORM TO YAP TONIGHT. THE
CIRCULATION WILL MOVE WEST AND BE NEAR 15N130E ON THURSDAY.
CONVERGENCE SOUTH OF THE CIRCULATION WILL BRING CONTINUE THE
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS YAP THROUGH
TUESDAY NIGHT. THE SAME CONVERGENCE WILL BRING SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS TO PALAU TUESDAY THROUGH WEDNESDAY.

ACTIVITY ALONG THE TROUGH WILL REMAIN NORTH OF CHUUK. SOUTH OF
THE TROUGH SOUTHERLY WINDS WILL PREVAIL ACROSS CHUUK TONIGHT. A
RIDGE OF HIGH PRESSURE WILL BUILD ACROSS CHUUK TUESDAY AND REMAIN
THROUGH WEDNESDAY. THIS RIDGE WILL KEEP SHOWERS ISOLATED THROUGH
THURSDAY. A SURFACE TROUGH WILL APPROACH CHUUK THURSDAY TURNING
WINDS TO THE NORTHEAST. THE TROUGH WILL PASS ACROSS CHUUK
THURSDAY NIGHT. WINDS WILL TURN SOUTHEAST FRIDAY AFTER THE TROUGH
PASSES. AT THIS TIME IT APPEARS MOISTURE WILL BE LIMITED WITH THE
TROUGH SO EXPECT ONLY A FEW CLOUDS WITH IT.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...NONE.
&&

$$

STANKO/ZIOBRO









000
FXPQ60 PGUM 150617
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
417 PM CHST MON SEP 15 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS ANOTHER ROUND OF SCATTERED SHOWERS STARTING TO
DEVELOP EAST OF THE MARIANAS WATERS. THE VAD WIND PROFILE REVEALS
SOUTHEAST WINDS OF 10 TO 15 KNOTS THROUGH THE LOWEST 10 THOUSAND
FEET OF THE AIR.

&&

.DISCUSSION...
MONSOON TROUGH RUNS JUST SOUTH OF GUAM WATERS WITH A TROPICAL
DISTURBANCE SLIDING TOWARD THE WEST ALONG IT. THIS IS KEEPING THE
SHOWERS A LITTLE MORE ACTIVE THAN USUAL. UPPER-LEVEL TROUGHING IS
FURTHER ENHANCING THE DYNAMICS AND ALLOWING ISOLATED THUNDERSTORM
CELLS TO DEVELOP. WENT AHEAD AND EXTENDED MOSTLY CLOUDY BY A
COUPLE OF DAYS AND TWEAKED THE HIGH TEMPERATURES ACCORDINGLY.
LATELY WE HAVE BEEN A BIT TOO OPTOMISTIC IN THE EXTENDED FORECAST.

EAST AND WEST SWELLS ARE NOT THAT IMPRESSIVE SEPARATELY...TOGETHER
THOUGH THEY ADD UP TO BETWEEN 4 AND 6 FEET COMBINED SEAS. THESE
SEAS WILL PERSIST THROUGH ABOUT WEDNESDAY THEN START TO GRADUALLY
DECLINE FOR THE SECOND HALF OF THE WEEK...LEADING TO BENIGN MARINE
CONDITIONS.

&&

.EASTERN MICRONESIA...

&&

.WESTERN MICRONESIA...

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...NONE.
&&

$$

STANKO/ZIOBRO







000
FXPQ60 PGUM 141959
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
559 AM CHST MON SEP 15 2014

.MARIANAS SYNOPSIS...
THE CENTER OF INVEST AREA 96W IS CURRENTLY PASSING AROUND 100
MILES SOUTH OF GUAM. BULK OF THE ASSOCIATED CONVECTION IS
DISPLACED TO THE NORTHEAST...NORTH AND NORTHWEST OF THE CENTER IN
THE VICINITY OF SURFACE TROUGHING. ZONE OF LOW-LEVEL CONVERGENCE
AND BAND OF ASSOCIATED CONVECTION CURRENTLY LIES OVER THE
FORECAST ZONES.

&&

.DISCUSSION...
SATELLITE AND RADAR TRENDS SUGGEST LATEST ROUND OF CONVECTION
WILL WIND DOWN AROUND MID MORNING...BUT DAY SHIFT WILL NEED TO
WATCH THIS CLOSELY TO SEE THAT THIS VERIFIES. MODEL GUIDANCE
SUGGESTS UNSETTLED WEATHER PATTERN WILL CONTINUE AT LEAST THROUGH
TUESDAY NIGHT. MODEL QPFS ALSO HINT THAT CONVECTION WILL CONTINUE
TO FAVOR THE NOCTURNAL MAXIMUM DURING THIS TIME FRAME...SO HAVE
ADDED SCATTERED SHOWERS TO THE FORECAST TONIGHT AND TUESDAY
NIGHT. BOOSTED WINDS FOR TONIGHT THROUGH DAY 3 TO RECONCILE WITH
MODEL GUIDANCE CONSENSUS WHICH CALLS FOR SOME DEVELOPMENT OF 96W
AS IT TRACKS TOWARD THE WEST-NORTHWEST. NEXT POSSIBLE WEATHER
MAKER COULD BE AN INVERTED SURFACE TROUGH THAT DEVELOPS OVER
CHUUK AND POHNPEI STATES ON WEDNESDAY. SYSTEM WOULD THEN POSSIBLY
AFFECT THE FORECAST ZONES WITH SCATTERED SHOWERS AROUND FRIDAY OR
SO. WILL WAIT FOR SIGNS OF DEVELOPMENT BEFORE MAKING ANY FORECAST
GRID ADJUSTMENTS.

&&

.MARINE...
MARINE GRIDS AGREED WELL WITH THE LATEST ALTIMETRY AND BUOY
READINGS...WHICH SHOW COMBINED SEAS IN THE 5 TO 6-FOOT RANGE.
BOTH EAST AND WEST SWELL WILL BE SUBSIDING AROUND MID
WEEK...ALLOWING RIP CURRENT RISK TO DECLINE TO LOW.

&&

.EASTERN MICRONESIA...
A DRY WEATHER PATTERN IS WELL ESTABLISHED ACROSS ALL 3 LOCALES.
12Z ASCAT ANALYSIS SHOWS THE MONSOON TROUGH NORTH OF CHUUK TRYING
TO LINK WITH THE SURFACE TROUGH ALREADY EXTENDING ACROSS THE
MARSHALL ISLANDS TO NEAR KOSRAE. LIGHT AND VARIABLE WINDS ARE
EXPECTED OVER ALL 3 LOCALES DUE TO THE PROXIMITY TROUGH TO EACH.
OVERALL WEATHER PATTERN REMAINS BENIGN THIS WEEK THOUGH MODELS
HINT AT SOME MOISTURE INCREASING AS THE TROUGH OVER THE MARSHALLS
SLOWLY SHIFTS WEST. MODELS STILL SHOW WEAK CIRCULATIONS
DEVELOPING WITHIN THE TROUGH THAT COULD PRODUCE SHOWERS BUT THE
SIGNAL REMAINS WEAK WITH LACK OF CONSENSUS BETWEEN MODELS.
THEREFORE...LATEST ISSUANCE WILL FOLLOW THE INHERITED FORECAST
WHICH MAINTAINS A DRY BIAS DURING NEXT FEW DAYS.

&&

.WESTERN MICRONESIA...
THE TROPICAL DISTURBANCE JUST SOUTH OF GUAM REMAINS THE DOMINANT
WEATHER FEATURE IN THE REGION. RIDGING REMAINS IN PLACE OVER
KOROR...AND EAST OF CHUUK. ISOLATED SHOWERS AND THUNDERSTORMS ON
CHUUK WILL GIVE WAY TO IMPROVED CONDITIONS MONDAY NIGHT AS THE
DISTURBANCE MOVES WEST. DRIER PATTERN SEEN IN THE EAST WILL BUILD
IN OVER CHUUK TUESDAY. FARTHER WEST...FAIR WEATHER WILL PERSIST
OVER KOROR THROUGH MUCH OF THE DAY...BUT CLOUDS AND SHOWERS WILL
GRADUALLY INCREASE OVER YAP TODAY. MODELS PROG THE DISTURBANCE TO
PASS JUST NORTH OF YAP ON TUESDAY. SCATTERED SHOWERS WERE ADDED
TO THE YAP FORECAST FOR TUESDAY...AND IF MODELS REMAIN
CONSISTENT...KOROR WILL NEED SCATTERED WORDING IN THE FORECAST
FOR TUESDAY AND/OR WEDNESDAY AS WELL. DRIER WEATHER WILL RETURN
THURSDAY TO BOTH LOCALES AS THE DISTURBANCE CONTINUES NORTHWEST
AWAY FROM YAP AND PALAU.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...NONE.
&&

$$

MCELROY/M. AYDLETT







000
FXPQ60 PGUM 140805
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
605 PM CHST SUN SEP 14 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D AND LIGHTNING DATA SHOW SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS JUST EAST OF THE MARIANAS WATERS STARTING TO MOVE
THROUGH. THE VAD WIND PROFILE REVEALS EAST WINDS OF 10 TO 15 KNOTS
THROUGH THE LOWEST 12 THOUSAND FEET OF THE AIR.

&&

.DISCUSSION...
A WEAK TROPICAL DISTURBANCE IS PRODUCING SCATTERED SHOWERS THAT
ARE BEGINNING TO MOVE THROUGH THE MARIANAS. AN UPPER-LEVEL TROUGH
IS PROVIDING A BIT OF EXTRA DYNAMIC SUPPORT ALLOWING SOME TO
BECOME THUNDERSTORMS. AFTER THE DISTURBANCE HAS PASSED THROUGH...
THERE WILL BE SOME RESIDUAL ACTIVITY AT LEAST SOMEWHAT FOLLOWING
THE DIURNAL CYCLE. THIS WILL BE MAINLY IN THE LATE NIGHT AND EARLY
MORNING HOURS.

&&

.MARINE...
COMBINED SEAS OF 3 TO 5 FEET WITH OCCASIONAL 6 FOOT VALUES WILL
CONTINUE THROUGH WEDNESDAY. AFTERWARD...SEAS ARE EXPECTED TO
GRADUALLY DIMINISH. THIS WILL LEAD TO BENIGN SEA CONDITIONS AGAIN
FOR THE WEEKEND.

&&

.EASTERN MICRONESIA...
A SURFACE RIDGE BETWEEN A MONSOON TROUGH NORTH OF CHUUK AND A
NEAR-EQUATORIAL TROUGH NEAR THE DATE LINE WILL CONTINUE TO PROMOTE
DRY WEATHER ACROSS POHNPEI...KOSRAE THRU MONDAY NIGHT AND NEAR
MAJURO UNTIL MONDAY AFTERNOON. AS THE MONSOON TROUGH GRADUALLY
SHIFTS WESTWARD ON TUESDAY...THE SURFACE RIDGE WILL ALSO DO THE
SAME. THIS SHOULD EVENTUALLY ALLOW THE NEAR-EQUATORIAL TROUGH TO
PROGRESS WESTWARD INTO THE REGION TOWARD MIDWEEK. A COUPLE OF
CIRCULATIONS EMBEDDED WITHIN THIS TROUGH COULD BRING A FEW SHOWERS
FOR ALL THE LOCATIONS NEAR MIDWEEK. THEN LIGHT TRADES FILTERING
WESTWARD FROM EAST OF THE DATE LINE COULD INTRODUCE ANOTHER ROUND OF
FAIR WEATHER AFTER MIDWEEK.

&&

.WESTERN MICRONESIA...
MODEST CONVERGING SOUTH WINDS SOUTHEAST OF A MONSOON CIRCULATION
NEAR THE MARIANAS WILL MAINTAIN A SLIGHT THREAT OF THUNDERSTORMS
OVER CHUUK THRU MONDAY NIGHT. BY TUESDAY...THE SURFACE RIDGE
CURRENTLY NEAR POHNPEI IS GOING TO MIGRATE WESTWARD AND PROVIDE
PARTLY CLOUDY SKIES DURING MIDWEEK. TOWARD THE WEEKEND...THE
LEADING EDGE OF A NEAR-EQUATORIAL TROUGH FROM EASTERN MICRONESIA
COULD INCREASE THE CHANCE OF SHOWERS.

A RIDGE OF HIGH PRESSURE WELL SOUTHEAST OF TYPHOON KALMAEGI OVER
LUZON IS EXPECTED TO DOMINATE THE WEATHER OVER THE REPUBLIC OF PALAU
AND YAP STATE UNTIL MONDAY AFTERNOON. WITH KALMAEGI ENTERING THE
SOUTH CHINA SEA MONDAY AFTERNOON...THE HIGH WILL ALSO MOVE WESTWARD
TOWARD MINDANAO. THE NEXT WEATHER-MAKER WILL BE THE MONSOON
CIRCULATION CURRENTLY PASSING SOUTH OF GUAM. IT WILL LIKELY PRODUCE
A PERIOD OF UNSTABLE CONDITIONS FOR BOTH LOCALES FROM MONDAY NIGHT
TO WEDNESDAY. IT IS STILL A BIT TOO EARLY TO PINPOINT THE ONSET OF
SCATTERED SHOWERS AT THIS POINT. FOR NOW...HAVE MENTIONED
THUNDERSTORMS AND SLIGHTLY STRONGER WINDS IN THE FORECAST. THIS
CIRCULATION SHOULD TAKE A SIMILAR TRACK AS TYPHOON KALMAEGI BY
PULLING NORTHWEST OF THE AREA AFTER MIDWEEK. IN RESPONSE...ANOTHER
RIDGE OF HIGH PRESSURE WILL FORM AND DRY THINGS OUT.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...NONE.
&&

$$

STANKO/CHAN









000
FXPQ60 PGUM 131953
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
553 AM CHST SUN SEP 14 2014

.MARIANAS SYNOPSIS...
RADAR IMAGERY HAS BEEN UNAVAILABLE SO FAR THIS MORNING...SO
ANALYSIS AND FORECAST DEPEND MORE ON SATELLITE IMAGERY. THE
MONSOON TROUGH STILL PASSES THROUGH THE FORECAST ZONES. JTWC
INVEST AREA 96W IS MOVING WESTWARD AWAY FROM CHUUK. INVERTED
SURFACE TROUGH TO THE NORTH OF 96W IS APPROACHING THE FORECAST
ZONES FROM THE EAST.

&&

.DISCUSSION...
ANIMATED IR SATELLITE IMAGERY SHOWS THE LATEST RESIDENT MCS IS
BEGINNING TO WIND DOWN JUST IN SIMILAR FASHION TO THE ONE FROM
YESTERDAY...SO FORECAST FOR TODAY IS DEJA VU...CALLING FOR
SCATTERED SHOWERS TO TAPER TO ISOLATED BY MID MORNING. SURFACE
TROUGH APPROACHING FROM THE EAST WILL PROVIDE A LOW-LEVEL FOCUS
FOR CONVECTION THROUGH MONDAY MORNING. SATELLITE TRENDS...MODEL
GUIDANCE AND PERSISTENCE SUGGEST ANOTHER ROUND OF NOCTURNAL
CONVECTION TONIGHT AND EARLY ON MONDAY MORNING. MODELS KEEP
MONSOON TROUGH AND DEEP MOISTURE AROUND AT LEAST THROUGH
WEDNESDAY NIGHT...SO HAVE EXTENDED MOSTLY CLOUDY/ISOLATED
THUNDERSTORM WORDING THROUGH WEDNESDAY NIGHT.

&&

.MARINE...
TYPHOON KALMAEGI IS FAR ENOUGH EAST OF LUZON TO DIRECT LONG
PERIOD WEST SWELL TOWARD THE FORECAST ZONES. HAVE CONSEQUENTLY
BOOSTED WEST SWELL HEIGHTS 1 FOOT MONDAY AND TUESDAY. INCREASE IN
WEST SWELL WILL SPELL A RETURN TO MODERATE RIP CURRENT RISK ON
RESPECTIVE EXPOSURES ON MONDAY.

&&

.EASTERN MICRONESIA...
12Z ASCAT ANALYSIS SHOWS THE TROPICAL DISTURBANCE TO BE CENTERED
BETWEEN POHNPEI AND CHUUK NEAR 8N155E. A WEAK TROUGH CURVES
EASTWARD FROM THE DISTURBANCE TO NEAR KOSRAE. SCATTERED SHOWERS
WERE CONTINUED IN THE POHNPEI FORECAST THROUGH NOON TODAY AS
CONVERGENCE ON THE SOUTHEAST SIDE OF THE DISTURBANCE WILL
MAINTAIN ACTIVE WEATHER THERE THROUGH THE MORNING. WILL NEED TO
CONTINUE TO WATCH THIS BAND OF WEATHER TODAY AS THE DISTURBANCE
SLOWLY SHIFTS WEST. DRIER WEATHER IS SEEN FARTHER EAST OVER
KOSRAE AND MAJURO. A WEAK TROUGH STRETCHES FROM NEAR MAJURO TO
THE DATE LINE. MODELS MAINTAIN BENIGN WEATHER CONDITIONS IN THE
VICINITY OF THIS TROUGH. THEREFORE...ISOLATED SHOWERS ARE
EXPECTED THROUGH THE LONG TERM ON BOTH MAJURO AND KOSRAE. PRIMARY
EFFECT OF THE TROUGH WILL BE TO MAINTAIN LIGHT TO GENTLE WINDS ON
KOSRAE AND MAJURO THE NEXT COUPLE DAYS. THIS FEATURE WILL SHIFT
WEST AND ALLOW DRIER WEATHER TO REACH POHNPEI ON MONDAY.

&&

.WESTERN MICRONESIA...
RIDGING OVER YAP AND KOROR THIS MORNING WILL KEEP PLEASANT
WEATHER IN PLACE THERE THROUGH MONDAY. MAIN WEATHER FEATURE THE
NEXT FEW DAYS WILL BE A DISTURBANCE NEAR CHUUK. ISOLATED SHOWERS
AND THUNDERSTORMS WILL PERSIST ON CHUUK THROUGH MONDAY NIGHT
BEFORE THE DISTURBANCE DEPARTS CHUUK STATE FOR YAP AND KOROR.
WILL HAVE TO WATCH CHUUK CLOSELY IN CASE SHOWERS BACK BUILD ON
THE EAST SIDE OF THE DISTURBANCE AND INCREASE THERE TODAY OR
MONDAY. CLOUDS WILL INCREASE OVER YAP ON MONDAY WITH ISOLATED
SHOWERS AND THUNDERSTORMS MOVING IN BY MONDAY NIGHT OVER YAP AND
TUESDAY OVER KOROR. EXACT TRACK OF THIS DISTURBANCE REMAINS
UNCERTAIN...POSSIBLY NORTH OF YAP OR OVER YAP. LONG TERM WIND
FORECASTS REMAIN LOW CONFIDENCE DUE TO THE UNCERTAINTY IN THE
EVOLUTION OF THIS SYSTEM. DRIER WEATHER WILL BUILD IN BEHIND THIS
DISTURBANCE OVER CHUUK ON THURSDAY.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...NONE.
&&

$$

MCELROY/M. AYDLETT







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