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000
FXPQ60 PGUM 010919
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
719 PM CHST MON SEP 1 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS ISOLATED SHOWERS AND THUNDERSTORMS MOVING
THROUGH THE MARIANAS WATERS. THE VAD WIND PROFILE REVEALS MONSOON
FLOW...MAINLY FROM THE WEST-SOUTHWEST...AT 10 TO 15 KNOTS THROUGH
THE LOWEST 20 THOUSAND FEET OF THE AIR.

&&

.DISCUSSION...
MONSOON TROUGH IS NOW NORTH OF SAIPAN AND WILL BE THE STRONGEST
INFLUENCE ON OUR WEATHER THE NEXT COUPLE OF DAYS.CLIMATE
PREDICTION CENTER MJO UPDATE SHOWS THE MADDEN-JULIAN OSCILLATION
IS CURRENTLY WEAK AND INCOHERENT...SO THE MONSOON TROUGH IS NOT
EXPECTED TO STRENGTHEN SIGNIFICANTLY. EVEN THE GFS40 DOES NO MORE
THAN BRING A SURGE OF 25 TO 30 KNOTS CREATING A TROPICAL
DEPRESSION NORTHWEST OF KOROR WHICH DOES NOT DO MUCH MORE THAN
THAT. COMBINED SEAS REMAIN NEAR 2 TO 4 FEET ALL THIS WEEK...WITH
POSSIBLY A SPARSE 5 FOOT READING THROWN IN FOR VARIETY. THESE ARE
ALL WELL BELOW ADVISORY CRITERIA...SO NO ADVISORIES ARE FORESEEN.

&&

.EASTERN MICRONESIA...
LIGHT TO GENTLE TRADE WINDS ARE GRADUALLY FILTERING WESTWARD
ACROSS THE REGION FROM NEAR THE DATE LINE. LATEST VISIBLE AND
ASCAT SATELLITE IMAGERY REVEAL A SERIES OF SURFACE IMPULSES
EMBEDDED WITHIN THESE TRADES. THE FIRST ONE IS JUST WEST OF
KWAJALEIN NEAR 167E AND THE SECOND ONE NEAR MAJURO THIS EVENING.
THE FIRST ONE IS MOVING MUCH SLOWER DUE TO A SURFACE RIDGE OVER
POHNPEI BLOCKING ITS PROGRESSION. THEREFORE FAIR WEATHER WILL
LINGER NEAR POHNPEI THRU TUESDAY EVENING. ON THE OTHER HAND...THE
SECOND IMPULSE WILL MAINTAIN WETNESS FOR MAJURO THRU TUESDAY
MORNING AND SPREAD IT INTO KOSRAE BY TUESDAY AFTERNOON. IT IS
EXPECTED TO MERGE TOGETHER WITH THE FIRST IMPULSE ON TUESDAY AND
THEN APPROACH POHNPEI ON TUESDAY NIGHT. AFTER THE PASSAGE OF THIS
COMBINED SYSTEM...A BRIEF PERIOD OF DRIER WEATHER IS POSSIBLE FOR
KOSRAE AND POHNPEI AFTER MIDWEEK. FOR MAJURO...MORE SURFACE
IMPULSES FROM UPSTREAM EAST OF THE DATE LINE WILL KEEP SHOWERS
AROUND UNTIL THIS WEEKEND. THESE SAME IMPULSES WILL ALSO AFFECT
KOSRAE AND POHNPEI BY THIS WEEKEND.

&&

.WESTERN MICRONESIA...
AN AREA OF DIVERGENT WINDS ASSOCIATED WITH AN UPPER-LEVEL HIGH
CENTERED OVER THE PHILIPPINE SEA COULD STILL TRIGGER A FEW
THUNDERSTORMS NEAR CHUUK THIS EVENING. LATEST WV SATELLITE AND
MODEL GUIDANCE IMAGERY INDICATE A POOL OF MID-LEVEL DRY AIR
MIGRATING WESTWARD FROM NEAR POHNPEI. THIS DRY AIR MASS SHOULD
STABILIZE THINGS OVER CHUUK BY TUESDAY MORNING. BY THURSDAY...THE
FIRST OF A SERIES OF TRADE DISTURBANCES CURRENTLY OVER EASTERN
MICRONESIA WILL BEGIN TO IMPACT CHUUK WITH PERIODIC SHOWERS.

THE BROAD MONSOONAL CIRCULATION CENTERED JUST NORTH OF KOROR AT
11N135E IS SHOWING SIGNS OF STRENGTHENING THIS AFTERNOON.
MODERATE TO FRESH WINDS ARE APPEARING BOTH WEST AND SOUTH OF THE
CENTER. SOUNDING DATA FROM WSO KOROR ALSO DISPLAY A DEEP LAYER OF
10 TO 20-KNOT SOUTHWEST WINDS FROM THE SURFACE TO ABOUT 550MB.
THESE CONVERGING SOUTHWEST WINDS ALONG WITH NORTHEAST WINDS ABOVE
500MB WILL ENHANCE VERTICAL DEVELOPMENT. THEREFORE ANTICIPATE
SPORADIC DEEP CONVECTION TO FLARE UP OVER KOROR AND YAP THRU AT
LEAST WEDNESDAY AFTERNOON. IF THE CIRCULATION DEVELOP INTO A
MONSOON DEPRESSION BY WEDNESDAY...INCLEMENT WEATHER COULD PROLONG
BEYOND WEDNESDAY ACROSS KOROR AND YAP. AS THE CIRCULATION FINALLY
LIFTS NORTHWARD AFTER MIDWEEK...CONDITIONS SHOULD START TO
IMPROVE TOWARD THE WEEKEND.

SOUTHWEST SWELL AND WIND WAVES ASSOCIATED WITH THE MONSOON WINDS
WILL BEGIN TO BUILD ACROSS PALAU AND WESTERN YAP STATE TONIGHT
AND TUESDAY. THIS COULD CAUSE SURF TO REACH HAZARDOUS LEVELS BY
TUESDAY NIGHT...NEED TO CLOSELY MONITOR THIS SITUATION.

&&

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

$$

STANKO/CHAN









000
FXPQ60 PGUM 311918
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
518 AM CHST MON SEP 1 2014

.MARIANAS SYNOPSIS...
A WEAK MONSOON TROUGH RUNS EAST-WEST ALONG 16N JUST NORTH OF
SAIPAN. SATELLITE SHOWS SOME POCKETS OF DEEP CONVECTION NEAR AND
NORTH OF THE TROUGH...MAINLY NORTHWEST OF THE ISLANDS. ONE NEARLY
STATIONARY CLUSTER OF SHOWERS AND THUNDERSTORMS IS SITUATED
NORTHWEST OF GUAM...EXTENDING WEST FROM ROTA...BUT IT APPEARS TO
BE WEAKENING AND STRATIFYING OUT. MEANWHILE...A LARGE UPPER LOW IS
CENTERED WELL WEST OF WAKE ISLAND NEAR 19N159E...MOVING SLOWLY
WEST.

&&

.DISCUSSION...
BASED ON LATEST RADAR AND SATELLITE...HAVE REMOVED SCATTERED
MORNING SHOWERS FOR TINIAN AND SAIPAN AS MOST OF THE SHOWERS HAVE
DRIFTED SOUTH TO NEAR ROTA AND ARE SLOWLY DISSIPATING. BUT I HAVE
MAINTAINED ISOLATED SHOWERS AND THUNDERSTORMS FOR THE NEXT FEW
DAYS AS THE MONSOON TROUGH LINGERS JUST NORTH OF THE REGION. WITH
LIGHT SOUTHWEST WINDS...ISLAND THUNDERSTORMS ARE A POSSIBILITY FOR
GUAM THE NEXT COUPLE OF AFTERNOONS. AS FOR WEDNESDAY...LATEST GFS
AND ECMWF SHOW THE UPPER LOW WEST OF WAKE WEAKENING AS IT MOVES
SLOWLY WEST-NORTHWEST...PASSING WELL NORTH OF THE FAR NORTHERN
MARIANAS IN A MUCH-WEAKENED STATE ON WEDNESDAY. AS A RESULT HAVE
GONE BACK TO ISOLATED SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY
NIGHT...GIVING WAY TO PARTLY CLOUDY ON THURSDAY AS DRIER AIR MOVES
IN ALOFT.

&&

.MARINE...
A MODEST RISE OF ABOUT A FOOT IN EAST SWELL IS STILL EXPECTED
WEDNESDAY NIGHT AND THURSDAY...BUT RIP RISK SHOULD REMAIN LOW.
SEAS ARE EXPECTED TO DIMINISH AGAIN FOR THE WEEKEND.

&&

.EASTERN MICRONESIA...
LATEST MODEL GUIDANCE STILL INDICATES ISOLATED SHOWERS AND
THUNDERSTORMS LIKELY FOR MAJURO FOR THE NEXT COUPLE OF DAYS. WEAK
TRADE-WIND CONVERGENCE TO THE EAST OF MAJURO IS BEGINNING TO MAKE
ITSELF KNOWN WITH INCREASING CONVECTION. THIS CONVECTION IS
STEADILY MOVING TOWARD THE WEST AND WILL LIKELY AFFECT MAJURO
TONIGHT. SCALED BACK THE FORECAST A BIT FOR TODAY BUT THOUGHT IT
WOULD BE PRUDENT TO LEAVE SLIGHT CHANCE OF THUNDERSTORMS IN THE
FORECAST AS THE CONVERGENCE ZONE APPROACHES THE ATOLL. THE
CONVERGENCE ZONE WILL DRIFT WESTWARD THROUGH THE NEXT FEW
DAYS...BRINGING INCREASED CLOUD COVER AND A MORE ACTIVE PATTERN TO
KOSRAE TONIGHT AND POHNPEI TUESDAY. AS THE CONVERGENCE WEAKENS AND
DRIFTS NORTHWESTWARD BEYOND MIDWEEK...EXPECT RELATIVELY DRIER
CONDITIONS TO RETURN TO MAJURO AND KOSRAE WEDNESDAY AND POHNPEI
THURSDAY.

&&

.WESTERN MICRONESIA...
THE MONSOON TROUGH AND DEPRESSION REMAIN THE PRIMARY WEATHER
PRODUCER OVER WESTERN MICRONESIA. MODELS INDICATE BOTH FEATURES WILL
CONTINUE TO STRENGTHEN OVER THE NEXT FEW DAYS. THE MONSOON DEPRESSION
IS EXPECTED TO CONTINUE TO DRIFT TOWARD THE WEST-NORTHWEST. THIS
SCENARIO WILL CREATE AN UNSTABLE PATTERN OVER PALAU AND YAP THROUGH
AT LEAST WEDNESDAY. SURGES ALONG THE TROUGH MAY BRING SHORT PERIODS
OF SCATTERED SHOWERS TO KOROR OVER THE NEXT FEW DAYS. ENHANCED
CONVERGENCE NEAR YAP IS GENERATING SCATTERED SHOWERS OVER AND JUST
SOUTHWEST OF THE ISLAND THIS MORNING. THESE SHOWERS WILL CONTINUE
TO PROGRESS WEST-NORTHWESTWARD THROUGH THE DAY...KEEPING SCATTERED
SHOWERS AND A FEW THUNDERSTORMS OVER YAP UNTIL THIS EVENING. EVEN
THOUGH MOST OF THE CONVECTION IS EXPECTED TO REMAIN SOUTH OF
YAP... IT WILL BE CLOSE ENOUGH TO MAINTAIN SLIGHT CHANCE OF
THUNDERSTORMS IN THE FORECAST THROUGH WEDNESDAY. AS THE CIRCULATION
CONTINUES TO DRIFT AWAY...MORE STABLE CONDITIONS WILL MOVE INTO
PALAU FOR THE LAST HALF OF THE WEEK. FOR CHUUK...CONTINUED TO
FOLLOW PERSISTENCE. MODELS INDICATE THE MONSOON TROUGH WILL RETREAT
WESTWARD AS TRADE WINDS TO RETURN TO THE STATE. A WEAK CONVERGENCE
ZONE MOVING THROUGH EASTERN MICRONESIA WILL BRING INCREASING CLOUD
COVER AND ENHANCED CONVECTION BACK TO CHUUK BY MIDWEEK.

&&

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

$$

MIDDLEBROOKE/KLEESCHULTE







000
FXPQ60 PGUM 310724
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
524 PM CHST SUN AUG 31 2014

.MARIANAS SYNOPSIS...
A DEVELOPING MONSOON TROUGH STRETCHES EAST-NORTHEASTWARD FROM
MINDANAO THRU A BROAD CIRCULATION CENTERED NEAR KOROR AT
8N137E...PASSES SOUTH OF GUAM TO END NORTHWEST OF THE MARSHALL
ISLANDS AT 14N161E. AT THE UPPER LEVELS...A HIGH IS CENTERED WEST
OF GUAM NEAR 14N140E AND A LOW WEST OF WAKE ISLAND AT 19N160E.
CONVECTION OVER THE CNMI INDUCED BY DIVERGENT FLOW ASSOCIATED
WITH THE HIGH HAS DISSIPATED.

&&

.DISCUSSION...
THE MONSOON TROUGH WILL GRADUALLY LIFT NORTHWARD AND PROVIDE
MODEST CONVERGENT SURFACE WINDS ACROSS THE MARIANAS FOR THE NEXT
FEW DAYS. THE UPPER HIGH IS EXPECTED TO REMAIN QUASI-STATIONARY
AND SUSTAIN DIVERGENT FLOW THRU TONIGHT. AS A RESULT...THERE IS A
GOOD CHANCE FOR CONVECTION TO FIRE BACK UP NEAR TINIAN AND SAIPAN
DURING THE DIURNAL MAX AFTER MIDNIGHT. BY MONDAY NIGHT...THE UPPER
LOW DRIFTING WEST-SOUTHWESTWARD TOWARD THE MARIANAS FROM NEAR
WAKE ISLAND WILL INTRODUCE MARGINAL SUBSIDENCE OVER THE MARIANAS.
THIS SHOULD ALLOW SHOWER COVERAGE TO STAY AT ISOLATED CATEGORY
THRU TUESDAY. AS THE LOW STALLS NEAR THE NORTHERN CNMI ON
WEDNESDAY...DIVERGENCE TO ITS SOUTH COULD SPARK OFF ANOTHER ROUND
OF CONVECTION OVER OUR FORECAST AREA. AFTERWARD...THE WEAKENING
UPPER LOW ALONG WITH A NEUTRAL AREA BETWEEN THE DEPARTING MONSOON
TROUGH AND ADVANCING TRADES MIGHT PROMOTE A PERIOD OF DRIER
WEATHER TOWARD THE WEEKEND.

&&

.MARINE...
COMBINED SEAS ARE GOING TO RANGE BETWEEN 2 AND 4 FEET THRU
TUESDAY. BY WEDNESDAY...BUILDING EAST SWELL GENERATED BY ADVANCING
TRADES WILL CAUSE SEAS TO RISE AND REACH 4 TO 5 FEET.

&&

.EASTERN MICRONESIA...
LATEST ASCAT IMAGERY REVEALS BROAD AND RELATIVELY DRY SOUTHEAST TO
SOUTH FLOW ACROSS EASTERN MICRONESIA BENEATH A REGION OF UPPER-LEVEL
CONVERGENCE. BIGGEST QUESTION MARK REVOLVES AROUND AN MCS THAT HAS
DEVELOPED ON THE SOUTH SIDE OF A MID TO UPPER-LEVEL LOW CENTERED
NORTH OF POHNPEI. MODELS ARE NOT HANDLING THIS FEATURE. BELIEVE MCS
WILL OUTRUN ITS UPPER-LEVEL SUPPORT SO WILL LEAVE SCATTERED SHOWERS
OUT OF THE POHNPEI FORECAST FOR NOW. DID FACTOR IN SOME OF THE
OVERNIGHT FORECAST RISK FOR POHNPEI VIA SLIGHT CHANCE THUNDER
WORDING. OTHERWISE...FORECASTS CLOSELY FOLLOW PERSISTENCE. SATELLITE
TRENDS SUGGEST RELATIVELY DRY WEATHER PATTERN WILL CONTINUE ACROSS
EASTERN MICRONESIA A BIT LONGER. MODELS WAIT TO PROPAGATE A ZONE OF
TRADE-WIND CONVERGENCE IN FROM THE EAST AROUND MID WEEK...SO TRIMMED
BACK THE ONSET OF MOSTLY CLOUDY SKIES TILL THEN FOR ALL 3 FORECAST
LOCALES.

LATEST ALTIMETRY SHOWED SEA HEIGHTS SUBSIDING A BIT NEAR MAJURO.
ACCORDINGLY SHAVED A FOOT FROM COMBINED SEAS FOR THAT LOCATION.

&&

.WESTERN MICRONESIA...
MONSOON DEPRESSION AND MONSOON TROUGH REMAIN THE SALIENT FEATURES TO
WATCH. MONSOON DEPRESSION IS CURRENTLY CENTERED VERY CLOSE TO KOROR.
DEVELOPING MONSOONAL BAND IS CAUSING WINDS AND SEAS TO RISE FOR
KOROR AND YAP. WAVE WATCH GUIDANCE DOES CAPTURE THIS SO HAVE RAMPED
THESE UP CONSIDERABLY FOR TONIGHT THROUGH WEDNESDAY VERSUS THE
INHERITED FORECAST. HAVE INCREASED SHOWER COVERAGE FOR KOROR
TONIGHT. FUTURE SHIFTS MAY NEED TO ADD MORE PERIODS OF SCATTERED
SHOWERS AND BEEF UP THE WINDS AN ADDITIONAL 5 KT FOR BOTH YAP AND
KOROR IF THE MONSOON DEPRESSION CONSOLIDATES FURTHER. HOWEVER...BEST
CONVERGENCE IS LOCATED ON THE SOUTHERN AND WESTERN QUADRANTS OF THE
MONSOON DEPRESSION. THIS ARGUES FOR LIMITING MENTION OF SCATTERED
SHOWERS IN THE YAP AND KOROR FORECASTS FOR THE TIME BEING. CHUUK
FORECAST FOLLOWS PERSISTENCE AS MONSOON TROUGH IS STILL EXPECTED TO
RETREAT WESTWARD AWAY FROM WENO ISLAND DURING THE NEXT FEW DAYS AND
ALLOW TRADE WINDS TO RETURN.

&&

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

$$

CHAN/MCELROY






000
FXPQ60 PGUM 310136 AAA
AFDPQ

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TIYAN GU
1136 AM CHST SUN AUG 31 2014

.UPDATE...
WEAK SURFACE TROUGHING WEST OF THE MARIANAS AND DIVERGENT FLOW
NORTHEAST OF AN UPPER-LEVEL HIGH CENTERED WEST OF GUAM NEAR
14N141E ARE COMBINING TO TRIGGER SHOWERS AND THUNDERSTORMS MAINLY
NORTH OF GUAM THIS AFTERNOON.

&&

.PREV DISCUSSION... /ISSUED 756 AM CHST SUN AUG 31 2014/

MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS ISOLATED SHOWERS MOVING THROUGH THE MARIANAS
WATERS. SCATTERED SHOWERS ARE SHOWN JUST NORTH AND JUST SOUTH OF
THE COASTAL FORECAST ZONES. THE VAD WIND PROFILE REVEALS SOUTHEAST
WINDS OF 5 TO 8 KNOTS THROUGH THE LOWEST 2 THOUSAND FEET OF THE
AIR.

DISCUSSION...
WITH THE UPPER-LEVEL LOW HAVING MOVED AWAY AND THE MONSOON TROUGH
NOT ARRIVED YET...THERE WERE NO THUNDERSTORMS LAST NIGHT AND THERE
HAVE NOT BEEN ANY YET THIS MORNING. WITH SOUTHEAST WINDS OF UP TO
8 KNOTS...WENT AHEAD AND REMOVED THUNDERSTORMS TODAY. LEFT THEM IN
TONIGHT THROUGH WEDNESDAY NIGHT AS THE MONSOON TROUGH MUSCLES ITS
WAY IN. SEA HEIGHTS WILL REMAIN 2 TO 4 FEET THROUGH THE WEEK.

EASTERN MICRONESIA...
FAIR CONDITIONS PREVAIL OVER EASTERN MICRONESIA THIS MORNING.
PLEASANT CONDITIONS WILL CONTINUE ACROSS THE REGION THROUGH THE
REMAINDER OF THE WEEKEND. ON MONDAY...A WEAK TROUGH WILL MOVE INTO
THE REGION...BRINGING AN INCREASE IN CLOUD COVER AND CONVECTION TO
MAJURO MONDAY. THIS TROUGH WILL DRIFT WESTWARD...BRINGING THESE
CONDITIONS TO KOSRAE MONDAY NIGHT AND POHNPEI TUESDAY. FAIR WEATHER
WILL THEN RETURN TO MAJURO EARLY WEDNESDAY AND SPREAD WESTWARD WITH
DRIER CONDITIONS EXPECTED TO RETURN TO KOSRAE WEDNESDAY AND POHNPEI
THURSDAY.

LONG PERIOD SOUTHEAST SWELL PRODUCED BY PERSISTENT MODERATE TO FRESH
WINDS NEAR FIJI AND SAMOA IN THE SOUTHERN HEMISPHERE WILL CONTINUE
TO IMPACT KOSRAE AND POHNPEI STATES FOR A COUPLE MORE DAYS. SLIGHTLY
ELEVATED SURF AND RIP CURRENT RISKS ARE ANTICIPATED ALONG SOUTH AND
SOUTHEAST FACING SHORES BUT HAZARDOUS SURF IS NOT EXPECTED.

WESTERN MICRONESIA...
A MONSOON TROUGH HAS DEVELOPED OVER WESTERN MICRONESIA. IT EXTENDS
EASTWARD FROM NEAR 10N130E THROUGH A BROAD CIRCULATION CENTERED WEST
OF CHUUK NEAR 7N144E...THEN CONTINUES EAST-SOUTHEASTWARD TO END NEAR
5N156E. CONDITIONS REMAIN PLEASANT TODAY NORTH OF THE TROUGH. THIS
INCLUDES BOTH YAP AND CHUUK. UNSTABLE CONDITIONS OVER KOROR WILL
CONTINUE THROUGH THE END OF THE WEEK. MOST OF THE CONVECTION THIS
MORNING IS SOUTH AND WEST OF KOROR AND EXPECTED TO REMAIN THERE
THROUGH THE DAY. DUE TO THE PROXIMITY OF THE ACTIVITY...DECIDED TO
INCLUDE A SLIGHT CHANCE OF THUNDERSTORMS FOR KOROR TODAY. CONVECTION
IS THEN EXPECTED TO INCREASE AGAIN ON MONDAY. PERIODS OF SCATTERED
SHOWERS ARE POSSIBLE THROUGH THE WEEK...THOUGH TIMING OF THESE
EVENTS IS DIFFICULT AT THE PRESENT TIME. MOST OF THE CONVECTION WILL
REMAIN SOUTH OF YAP THROUGH THE WEEK...THOUGH THE TROUGH DOES DRIFT
CLOSE ENOUGH TO INCLUDE A SLIGHT CHANCE OF THUNDERSTORMS THERE
MONDAY AND TUESDAY. PLEASANT WEATHER WILL PREVAIL AT CHUUK FOR THE
NEXT FEW DAYS. CHUUK WILL BEGIN TO SEE AN INCREASE IN CONVECTION
WEDNESDAY AS A WEAK TROUGH APPROACHES THE STATE FROM EASTERN
MICRONESIA.

&&

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

$$

STANKO/KLEESCHULTE/CHAN







000
FXPQ60 PGUM 302156
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
756 AM CHST SUN AUG 31 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS ISOLATED SHOWERS MOVING THROUGH THE MARIANAS
WATERS. SCATTERED SHOWERS ARE SHOWN JUST NORTH AND JUST SOUTH OF
THE COASTAL FORECAST ZONES. THE VAD WIND PROFILE REVEALS SOUTHEAST
WINDS OF 5 TO 8 KNOTS THROUGH THE LOWEST 2 THOUSAND FEET OF THE
AIR.

&&

.DISCUSSION...
WITH THE UPPER-LEVEL LOW HAVING MOVED AWAY AND THE MONSOON TROUGH
NOT ARRIVED YET...THERE WERE NO THUNDERSTORMS LAST NIGHT AND THERE
HAVE NOT BEEN ANY YET THIS MORNING. WITH SOUTHEAST WINDS OF UP TO
8 KNOTS...WENT AHEAD AND REMOVED THUNDERSTORMS TODAY. LEFT THEM IN
TONIGHT THROUGH WEDNESDAY NIGHT AS THE MONSOON TROUGH MUSCLES ITS
WAY IN. SEA HEIGHTS WILL REMAIN 2 TO 4 FEET THROUGH THE WEEK.

&&

.EASTERN MICRONESIA...
FAIR CONDITIONS PREVAIL OVER EASTERN MICRONESIA THIS MORNING.
PLEASANT CONDITIONS WILL CONTINUE ACROSS THE REGION THROUGH THE
REMAINDER OF THE WEEKEND. ON MONDAY...A WEAK TROUGH WILL MOVE INTO
THE REGION...BRINGING AN INCREASE IN CLOUD COVER AND CONVECTION TO
MAJURO MONDAY. THIS TROUGH WILL DRIFT WESTWARD...BRINGING THESE
CONDITIONS TO KOSRAE MONDAY NIGHT AND POHNPEI TUESDAY. FAIR WEATHER
WILL THEN RETURN TO MAJURO EARLY WEDNESDAY AND SPREAD WESTWARD WITH
DRIER CONDITIONS EXPECTED TO RETURN TO KOSRAE WEDNESDAY AND POHNPEI
THURSDAY.

LONG PERIOD SOUTHEAST SWELL PRODUCED BY PERSISTENT MODERATE TO FRESH
WINDS NEAR FIJI AND SAMOA IN THE SOUTHERN HEMISPHERE WILL CONTINUE
TO IMPACT KOSRAE AND POHNPEI STATES FOR A COUPLE MORE DAYS. SLIGHTLY
ELEVATED SURF AND RIP CURRENT RISKS ARE ANTICIPATED ALONG SOUTH AND
SOUTHEAST FACING SHORES BUT HAZARDOUS SURF IS NOT EXPECTED.

&&

.WESTERN MICRONESIA...
A MONSOON TROUGH HAS DEVELOPED OVER WESTERN MICRONESIA. IT EXTENDS
EASTWARD FROM NEAR 10N130E THROUGH A BROAD CIRCULATION CENTERED WEST
OF CHUUK NEAR 7N144E...THEN CONTINUES EAST-SOUTHEASTWARD TO END NEAR
5N156E. CONDITIONS REMAIN PLEASANT TODAY NORTH OF THE TROUGH. THIS
INCLUDES BOTH YAP AND CHUUK. UNSTABLE CONDITIONS OVER KOROR WILL
CONTINUE THROUGH THE END OF THE WEEK. MOST OF THE CONVECTION THIS
MORNING IS SOUTH AND WEST OF KOROR AND EXPECTED TO REMAIN THERE
THROUGH THE DAY. DUE TO THE PROXIMITY OF THE ACTIVITY...DECIDED TO
INCLUDE A SLIGHT CHANCE OF THUNDERSTORMS FOR KOROR TODAY. CONVECTION
IS THEN EXPECTED TO INCREASE AGAIN ON MONDAY. PERIODS OF SCATTERED
SHOWERS ARE POSSIBLE THROUGH THE WEEK...THOUGH TIMING OF THESE
EVENTS IS DIFFICULT AT THE PRESENT TIME. MOST OF THE CONVECTION WILL
REMAIN SOUTH OF YAP THROUGH THE WEEK...THOUGH THE TROUGH DOES DRIFT
CLOSE ENOUGH TO INCLUDE A SLIGHT CHANCE OF THUNDERSTORMS THERE
MONDAY AND TUESDAY. PLEASANT WEATHER WILL PREVAIL AT CHUUK FOR THE
NEXT FEW DAYS. CHUUK WILL BEGIN TO SEE AN INCREASE IN CONVECTION
WEDNESDAY AS A WEAK TROUGH APPROACHES THE STATE FROM EASTERN
MICRONESIA.

&&

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

$$

STANKO/KLEESCHULTE







000
FXPQ60 PGUM 300807
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
600 PM CHST SAT AUG 30 2014

.MARIANAS SYNOPSIS...
MCS THAT AFFECTED THE FORECAST ZONES THIS MORNING HAS STRATIFIED
OUT. NEWLY DESIGNATED JTWC INVEST AREA 90W IS CENTERED SOUTH-
SOUTHWEST OF GUAM NEAR 9N144E. 90W IS A BROAD AND WEAK SYSTEM WITH
NO DEEP CONVECTION CONCENTRATING NEAR THE CENTER. SOME DEEP
CONVECTION IS TAKING PLACE IN TRADE-WIND CONVERGENCE TO THE NORTH OF
THE CENTER OVER THE FORECAST ZONES.

&&

.DISCUSSION...
MODELS REMAIN IN GENERAL AGREEMENT IN KEEPING 90W UNORGANIZED DURING
THE NEXT SEVERAL DAYS. MONSOON TROUGH ON THE EAST SIDE OF 90W WILL
LIFT NORTHWARD THROUGH THE FORECAST ZONES TOMORROW...THEN TO THE
NORTH OF SAIPAN MONDAY THROUGH WEDNESDAY NIGHT. EXTENDED ISOLATED
THUNDER IN THE FORECAST GRIDS FROM SUNDAY THROUGH WEDNESDAY NIGHT
BASED ON PROXIMITY OF THE MONSOON TROUGH AND CONVERGENT MONSOONAL
FLOW OVER THE FORECAST ZONES. NEUTRAL POINT WITHIN THE MONSOON
TROUGH WILL INTRODUCE AN AFTERNOON ISLAND THUNDER COMPONENT TO THE
MIX FOR GUAM ON SUNDAY...BUT CHOSE TO BROAD BRUSH THIS INTO THE
FORECAST. BROAD AND LOOSE MONSOONAL PATTERN PERSISTS THROUGH
WEDNESDAY NIGHT...THEN RIDGING FROM THE NORTH USHERS IN A DRIER
TRADE-WIND PATTERN. MARINE CONDITIONS STILL LOOK BENIGN FOR THE
FORESEEABLE FUTURE WITH SEAS CONTINUING TO LINGER IN THE 2 TO 4-FOOT
RANGE.

&&

.EASTERN MICRONESIA...
FAIR CONDITIONS CONTINUE ACROSS MOST OF EASTERN MICRONESIA THIS
AFTERNOON. POHNPEI AND KOSRAE WILL CONTINUE TO SEE DRY WEATHER
THROUGH MIDWEEK. A WEAK DISTURBANCE THAT WAS OVER MAJURO TODAY
ALREADY WEAKENED AND FOUND NO SIGNIFICANT WEATHER SYSTEMS EAST OF
IT. AS THE FIRST TROUGH PROGRESSES WESTWARD...EXPECT TO SEE ONLY
INCREASING CLOUDINESS AT KOSRAE MONDAY AND AT POHNPEI TUESDAY.

LONG PERIOD SOUTHEAST SWELL PRODUCED BY PERSISTENT MODERATE TO FRESH
WINDS NEAR FIJI AND SAMOA IN THE SOUTHERN HEMISPHERE WILL CONTINUE
TO IMPACT KOSRAE AND POHNPEI STATES FOR ANOTHER FEW DAYS. SLIGHTLY
ELEVATED SURF AND RIP CURRENT RISKS ARE ANTICIPATED ALONG SOUTH AND
SOUTHEAST FACING SHORES BUT HAZARDOUS SURF IS NOT EXPECTED.

&&

.WESTERN MICRONESIA...
A BROAD CIRCULATION REMAINS TO THE WEST OF CHUUK SLOWLY MOVING
WESTWARD. AS THE SYSTEM PUSHES FURTHER WEST...EXPECT CONDITIONS TO
BE PLEASANT AT CHUUK UNTIL ABOUT WEDNESDAY. WINDS ARE SOMEWHAT
HIGHER AT KOROR THAN FORECAST. THIS MAY BE INDICATIVE OF
STREGTHENING OF THE MONSOON CIRCULATION APPROACHING YAP AND KOROR.
MAY NEED TO FURTHER ADJUST THE YAP AND KOROR FORECASTS TO REFLECT
THIS THROUGH MIDWEEK.

&&

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

$$

MCELROY/DEVITA










000
FXPQ60 PGUM 292248
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
848 AM CHST SAT AUG 30 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
MOVING THROUGH THE MARIANAS WATERS. THE VAD WIND PROFILE REVEALS
10 TO 16 KNOT EAST-NORTHEAST WINDS THROUGH THE LOWEST 10 THOUSAND
FEET OF THE AIR.

&&

.DISCUSSION...
SURFACE TROUGH MOVING THROUGH THE MARIANAS IS PROVIDING A FOCUSING
MECHANISM FOR LOW-LEVEL CONVERGENCE. THE UPPER LEVELS ARE MIXED
WITH DIRECTIONAL CONFLUENCE AND SPEED DIVERGENCE. IT WOULD SEEM
THE DIVERGENCE IS THE BIGGER AND IS JUST ENOUGH TO ENABLE A NUMBER
OF THESE SHOWERS TO BECOME THUNDERSTORMS. JUST ADDED SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS TO THE MORNING AS BOTH THE
TROUGH AND THE UPPER LOW SHOULD MOVE FARTHER AWAY. OTHERWISE JUST
REFRESHED THE WIND AND WAVE GRIDS. WAVE HEIGHTS SHOULD BE PEAKING
AT 3 TO 5 FEET TODAY WITH THE 5 FOOT VALUES NEAR SAIPAN WHILE GUAM
IS ABOUT A FOOT LOWER. THEN SEAS WILL DROP BY ABOUT A FOOT AND
REMAIN FAIRLY STEADY MOST OF THIS COMING WEEK.

&&

.EASTERN MICRONESIA...
FAIR CONDITIONS CONTINUE ACROSS MOST OF EASTERN MICRONESIA THIS
MORNING. POHNPEI AND KOSRAE WILL CONTINUE TO SEE DRY WEATHER THROUGH
MIDWEEK. A WEAK DISTURBANCE IS APPROACHING MAJURO THIS MORNING
BRINGING SCATTERED SHOWERS TO THE ATOLL TODAY. THESE SHOWERS WILL
QUICKLY DECREASE THIS AFTERNOON WITH DRY CONDITIONS RETURNING
TONIGHT. MODELS INDICATE THAT A WEAK TROUGH WILL MOVE INTO THE
MARSHALLS SUNDAY...BRINGING INCREASING CLOUDS TO MAJURO SUNDAY
AFTERNOON WITH INCREASED CONVECTION LIKELY THROUGH THE FIRST HALF OF
THE WEEK. AS THIS TROUGH PROGRESSES WESTWARD...EXPECT TO SEE ONLY
INCREASING CLOUDINESS AT KOSRAE MONDAY AND AT POHNPEI TUESDAY.

LONG PERIOD SOUTHEAST SWELL PRODUCED BY PERSISTENT MODERATE TO FRESH
WINDS NEAR FIJI AND SAMOA IN THE SOUTHERN HEMISPHERE WILL CONTINUE
TO IMPACT KOSRAE AND POHNPEI STATES UNTIL EARLY NEXT WEEK...AND
COULD SPREAD TO THE MARSHALL ISLANDS DURING THE WEEKEND. HIGHER
SURF AND RIP CURRENT RISKS ARE ANTICIPATED ALONG SOUTH AND SOUTHEAST
FACING SHORES BUT HAZARDOUS SURF IS NOT EXPECTED.

&&

.WESTERN MICRONESIA...
A BROAD CIRCULATION REMAINS TO THE WEST OF CHUUK. THIS SYSTEM IS
SLOWLY TRACKING WESTWARD. AS THE SYSTEM PUSHES FURTHER WEST...EXPECT
CONDITIONS TO CONTINUE TO IMPROVE THROUGH TODAY WITH PLEASANT
WEATHER LIKELY BY TONIGHT. AS THE WEAK SYSTEM OVER EASTERN
MICRONESIA APPROACHES CHUUK WEDNESDAY...EXPECT AN INCREASE IN CLOUD
COVER. A WEAK WIND REGIME IS CURRENTLY IN PLACE OVER YAP AND KOROR.
LATEST ANALYSIS SHOWS A WEAK TROUGH FORMING OVER YAP AND PALAU.
MODELS INDICATE THIS TROUGH WILL CONTINUE TO DEVELOP INTO A WEAK
MONSOONAL SYSTEM EARLY IN THE WEEK. THIS WILL BRING AN INCREASE IN
CLOUDS AND CONVECTION...ESPECIALLY TO KOROR...MONDAY THROUGH MIDWEEK.

&&

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

$$

STANKO/KLEESCHULTE







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