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000
FXPQ60 PGUM 240739
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
539 PM CHST THU APR 24 2014

.MARIANAS SYNOPSIS...
GUAM RADAR SHOWS ISOLATED SHOWERS MOVING THROUGH THE EASTERN GUAM
AND ROTA COASTAL WATERS. VIS SATELLITE SHOWS MORE CLOUDS AND
SHOWERS EXTENDING EASTWARD FROM GUAM AND ROTA TOWARDS 150E. DRIER
WEATHER IS SEEN NEAR TINIAN AND SAIPAN. A TROPICAL DISTURBANCE
SOUTHEAST OF GUAM CONTINUES TO SPIN NEAR CHUUK.

&&

.DISCUSSION...
UNCERTAINTY REMAINS IN THE FORECAST DUE TO THE TROPICAL
DISTURBANCE NEAR CHUUK. MODEL CONSENSUS MAINTAINS A SLOW APPROACH
WITH THIS DISTURBANCE COMING TOWARDS THE MARIANAS THIS WEEKEND.
THE DISTURBANCE IS EXPECTED TO KEEP A SLOW WESTWARD TRACK THE
NEXT COUPLE DAYS BEFORE TURNING NORTH OR NORTHWEST. MODELS THEN
SPLIT...TAKING THE DISTURBANCE OVER THE MARIANAS OR KEEPING IT
JUST WEST. WIND GRIDS WERE REFRESHED WITH LATEST MODEL TO KEEP
MODERATE EAST WINDS AT LEAST THROUGH SUNDAY. CLOUDS WERE ALSO
INCREASED FOR TONIGHT BASED ON SATELLITE IMAGERY OF WEATHER JUST
EAST OF GUAM THIS AFTERNOON. FORECAST FOR MONDAY AND NEXT WEEK
STILL DEPENDS HEAVILY ON WHETHER THE DISTURBANCE CONTINUES WEST
TOWARDS YAP...STALLS OUT SOUTH OF OR NEAR GUAM...OR PASSES OVER
THE MARIANAS HEADING NORTH. MODELS GENERALLY KEEP MUCH OF THE
MOISTURE JUST EAST OF THE MARIANAS THE NEXT COUPLE DAYS. MUCH
REMAINS TO BE SEEN AS THIS DISTURBANCE PROGRESSES THE NEXT FEW
DAYS.

&&

.MARINE...
NO MAJOR CHANGES TO THE MARINE GRIDS. A NORTH SWELL WILL BUILD ACROSS
THE MARIANAS SATURDAY NIGHT AND SUNDAY AS A RESULT OF FRESH WINDS
WELL NORTH OF THE REGION. WINDS ASSOCIATED WITH THE DISTURBANCE
NEAR CHUUK APPEAR TO HAVE LITTLE EFFECT ON REGIONAL SEAS THE NEXT
FEW DAYS. WILL HAVE TO WATCH CONDITIONS THE NEXT FEW DAYS FOR
DEVELOPMENTS.

&&

.EASTERN MICRONESIA...
THE EASTERN END OF A NEAR-EQUATORIAL TROUGH REACHES SOUTHEASTWARD
FROM A BROAD CIRCULATION CENTERED SOUTHEAST CHUUK STATE AT 7N154E TO
END SOUTHEAST OF KOSRAE AT EQ164E. THE TROUGH LIES NORTHEAST OF
BOTH POHNPEI AND KOSRAE MAINTAINING DRY CONDITIONS TODAY. A TRADE-
WIND DISTURBANCE MAY PROVIDE PERIODIC SHOWERS AND ISOLATED
THUNDERSTORMS FOR MAJURO AND KWAJALEIN THIS EVENING AND WILL
CONTINUE THROUGH THE FORECAST PERIOD AS IT DRIFTS WEST. POHNPEI
AND KOSRAE STATES WILL EXPERIENCE SIMILAR CONDITIONS UPON THE
ARRIVAL OF THE DISTURBANCE.

&&

.WESTERN MICRONESIA...
SATELLITE IMAGERY AND MODEL DATA AGREED ON THE WEAKENING OF THE
CIRCULATION EAST OF CHUUK FOR TODAY. MODELS INDICATE QUIETER
WEATHER FOR MAJORITY OF FORECAST PERIOD FOR CHUUK STATE AS THE
CIRCULATION MOVES WEST-NORTHWESTWARD. THE NEAR-EQUATORIAL TROUGH
SHOULD REMAIN SOUTH OF BOTH YAP AND KOROR THROUGH THE WEEKEND
TRENDING TOWARDS A DRIER REGIMEN WITH THE EXCEPTION OF A FEW
SHOWERS FROM A WEAK SURFACE TROUGH FOR YAP THIS EVENING AND FOR
KOROR LATE TONIGHT THROUGH FRIDAY AFTERNOON. FUTURE FORECAST
PERIODS MAY NEED TO BE ADJUSTED FOR ALL THREE LOCALES BASED ON
THE DEVELOPMENT OF THE DISTURBANCE NEAR CHUUK.

&&

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

$$

M. AYDLETT/ZIOBRO







000
FXPQ60 PGUM 232246
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
846 AM CHST THU APR 24 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS ISOLATED SHOWERS MOVING THROUGH THE MARIANAS
WATERS...MAINLY IN THE GUAM WATERS. SATELLITE SHOWS A TROPICAL
DISTURBANCE TO THE SOUTHEAST NEAR CHUUK WHICH COULD AFFECT THE
MARIANAS WEATHER STARTING FRIDAY. THE VAD WIND PROFILE REVEALS
WINDS OF 13 TO 20 KNOTS WITHIN THE LOWEST 6 THOUSAND FEET OF THE
AIR. DIRECTION TURNS FROM EAST-NORTHEAST NEAR THE SURFACE TO EAST-
SOUTHEAST ALOFT.

&&

.DISCUSSION...
ALOT OF UNCERTAINTY TODAY...ESPECIALLY IN THE DAY 3 AND BEYOND
FORECAST. GFS40 MODEL SPLITS THE TROPICAL DISTURBANCE NEAR CHUUK
INTO TWO PIECES. THE FIRST STAYS TOO FAR SOUTH TO HAVE ANY MORE
THAN JUST A MINIMAL AFFECT ON THE MARIANAS. THE OTHER MOVES
NORTHWARD TO THE EAST OF THE ISLANDS. THIS RESULTS IN A MUCH LESS
HAWKISH RAINFALL FORECAST. SINCE THE SHOWERS NORTH OF 10N ALSO
DISSOLVED OVER THE PAST 24 HOURS...DECIDED NOT TO UP THE SHOWERS
SO PREVIOUS FORECAST WAS ALMOST UNTOUCHED OTHER THAN SOME MINOR
TWEAKS TO THE COMBINED SEAS AND SWELLS.

&&

.MARINE...
GIVEN THE UNCERTAINTY OF THE EVOLUTION OF THE CURRENT PATTERN...
TENDED TOWARD THE LOWER OF THE TWO SEA HEIGHTS OUT OF THE LATEST
GLOBAL WAVE RUN OR THE CURRENT WAVE HEIGHT GRIDS. IF THE
CIRCULATION TO OUR NORTHEAST IS WEAKER THAN PROGGED BY THE GFS40
/OR FAILS TO FORM ENTIRELY/ WAVES WILL BE SUBSTANTIALLY LOWER.
THEREFORE...ATTEMPTED TO FACTOR THIS POSSIBILITY IN TO AT LEAST A
LIMITED DEGREE. A SMALL CRAFT ADVISORY IS UNLIKELY...HOWEVER A
HIGH SURF ADVISORY MAY STILL BE NECESSARY.

&&

.EASTERN MICRONESIA...
THE EASTERN END OF A NEAR-EQUATORIAL TROUGH REACHES SOUTHEASTWARD
FROM A BROAD CIRCULATION CENTERED JUST SOUTHEAST OF WENO ISLAND IN
CHUUK STATE AT 7N154E TO END SOUTHEAST OF KOSRAE AT EQ165E. MODEST
CONVERGING SOUTHEAST WINDS EAST OF THE CIRCULATION CAN STILL TRIGGER
A FEW THUNDERSTORMS NEAR POHNPEI TODAY. OTHERWISE WEAK RIDGING NORTH
OF THE TROUGH SHOULD MAINTAIN RELATIVELY DRY CONDITIONS FOR POHNPEI
UNTIL FRIDAY AFTERNOON...AND NEAR KOSRAE THRU THIS MORNING. FARTHER
EAST...A TRADE-WIND DISTURBANCE IS MOVING WESTWARD ACROSS THE
MARSHALL ISLANDS THIS MORNING. THEREFORE ANTICIPATE PERIODIC SHOWERS
WITH THE POSSIBILITY OF THUNDERSTORMS NEAR MAJURO UNTIL EARLY THIS
EVENING. BY LATE TONIGHT...DRYER NORTHEASTERLY TRADES SHOULD PROMOTE
PARTLY CLOUDY SKIES FOR THE ATOLL. AS THE DISTURBANCE PULLS WEST OF
THE MARSHALLS...IT WILL ALSO BRING WET WEATHER TO KOSRAE THIS
AFTERNOON AND POHNPEI BY FRIDAY NIGHT. LATEST ASCAT SATELLITE
IMAGERY REVEALS CONVERGING TRADES BETWEEN 4N AND 8N STRETCHING
EASTWARD FROM THE DATE LINE TO BEYOND 155W. THIS FEATURE COULD
RESUME SHOWERY WEATHER NEAR MAJURO BY SATURDAY EVENING...AND PROLONG
WETNESS FOR KOSRAE AND POHNPEI INTO NEXT WEEK.

&&

.WESTERN MICRONESIA...
DIFFLUENT LOW-LEVEL FLOW WEST OF A BROAD CIRCULATION CENTERED JUST
SOUTHEAST OF WENO ISLAND IN CHUUK STATE SHOULD ALLOW MAINLY ISOLATED
SHOWERS NEAR THE ISLAND THIS MORNING. THIS CIRCULATION IS EXPECTED
TO GRADUALLY DRIFT NORTHWESTWARD TODAY AND TONIGHT. AS A RESULT...
CONVERGING SURFACE WINDS NEAR AND EAST OF ITS CENTER WILL INCREASE
SHOWER COVERAGE NEAR CHUUK BY LATER THIS AFTERNOON. AFTERWARD A
TRADE DISTURBANCE FROM UPSTREAM NEAR THE MARSHALL ISLANDS MIGHT
GENERATE MORE SHOWERS THIS WEEKEND.

WITH THE WESTERN PORTION OF THE NEAR-EQUATORIAL TROUGH REMAINING
SOUTH OF KOROR AND YAP INTO THIS WEEKEND...MAINLY DRY WEATHER SHOULD
PREVAIL FOR BOTH LOCALES. THE ONLY EXCEPTION WILL BE A FEW SHOWERS
ASSOCIATED WITH A WEAK SURFACE TROUGH NEAR YAP TODAY AND KOROR ON
EARLY FRIDAY. FOR EARLY NEXT WEEK...THE FUTURE STATUS OF THE BROAD
CIRCULATION CURRENTLY NEAR CHUUK COULD PLAY A ROLE IN THE WEATHER OF
YAP AND KOROR.

&&

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

$$

STANKO/CHAN








000
FXPQ60 PGUM 230605
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
405 PM CHST WED APR 23 2014

.MARIANAS SYNOPSIS...NORTHEAST TRADE-WINDS AND WEAK HIGH PRESSURE
PREVAIL OVER THE MARIANAS.

&&

.DISCUSSION...
LITTLE CHANGE WAS MADE TO THE FORECAST. A RIDGE OF HIGH PRESSURE
OVER THE AREA IS WEAKENING. BEFORE THE RIDGE ENDS ITS INFLUENCE
ON THE AREA DRY AIR ASSOCIATED WITH IT WILL KEEP SHOWERS TO A
MINIMUM TONIGHT. ISOLATED SHOWERS ARE ALL THAT IS EXPECTED
THROUGH THURSDAY NIGHT. A CIRCULATION BETWEEN CHUUK AND POHNPEI
WILL MOVE WESTWARD. MODELS SHOW THIS CIRCULATION PASSING SOUTH OF
THE LOCAL AREA FRIDAY. MODELS DEBATE ON HOW CLOSE IT WILL GET TO
THE MARIANAS. SOME OF THE MODELS SHOW A SURFACE TROUGH EXTENDING
NORTH OF THE CIRCULATION OVER THE AREA. MODELS SHOW A CHANCE OF
SCATTERED SHOWERS OVER THE MARIANAS FRIDAY NIGHT THROUGH AT LEAST
SUNDAY. THE AREA OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THE
CIRCULATION HAVE MOVED SLIGHTLY NORTH OF 10N THIS AFTERNOON. WHILE
THIS LOOKS PROMISING FOR SCATTERED SHOWERS OVER THE MARIANAS THIS
WEEKEND CONFIDENCE IS NOT SO HIGH. THINGS COULD CHANGE AND KEEP
THESE SHOWERS SOUTH OF GUAM. WILL WAIT AND SEE BEFORE GOING FOR
SCATTERED OVER THE MARIANAS. DO HAVE HIGH CONFIDENCE IN THE MOSTLY
CLOUDY SKIES AND ISOLATED THUNDERSTORMS IN THE FORECAST FOR THE
WEEKEND.

&&

.MARINE...
AN EAST TRADE-WIND SWELL AND A NORTH SWELL WILL PREVAIL OVER THE
REGION THROUGH THE FORECAST. THE EAST SWELL WILL BE LARGE ENOUGH
TO GENERATE A MODERATE RIP CURRENT RISK ON EAST FACING REEFS THE
NEXT FEW DAYS.

&&

.EASTERN MICRONESIA...
CONVERGENCE ALONG THE NORTHEASTERN PERIPHERY OF THE CIRCULATION
SOUTHWEST OF POHNPEI NEAR 7N158E WILL BE THE MAIN WEATHER FEATURE
FOR POHNPEI AND KOSRAE STATES. FOR POHNPEI...SCATTERED SHOWERS
EXPECTED THIS EVENING BECOMING ISOLATED FOR THE REMAINDER OF THE
FORECAST PERIOD AS THE DISTURBANCE CONTINUES TO MOVE IN A
WESTWARD DIRECTION. MODELS SHOW KOSRAE STATE IN BETWEEN POCKETS
OF RAINBANDS WITH ISOLATED SHOWERS AS THE CIRCULATION MOVES OUT
OF THE REGION. TRADE-WIND CONVERGENCE COMING IN FROM THE EAST
WILL BRING A FEW MORE SHOWERS TO KOSRAE STATE FOR THE FIRST HALF
OF SUNDAY. FOR MAJURO...MAJORITY OF THE PERIOD TRADE-WIND SHOWERS
WILL BE ISOLATED BECOMING SCATTERED SUNDAY AND TAPERING OFF BY
MONDAY.

&&

.WESTERN MICRONESIA...
YAP STATE WILL MAINTAIN A DRIER TREND WITH THE NEAR-EQUATORIAL
TROUGH JUST SOUTH OF THE STATE FOR MOST OF THE FORECAST PERIOD.
AS THE CIRCULATION SOUTHEAST OF CHUUK MOVES WEST-NORTHWEST THE
WESTERN BANDS WILL PROVIDE A BETTER CHANCE OF SHOWERS ON SATURDAY
FOR YAP. LOW LEVEL CONVERGENCE PROVIDED SOME SHOWERS FOR KOROR
TODAY BUT DRIER CONDITIONS WILL KICK IN THIS EVENING. THE ARRIVAL
OF THE NEAR-EQUATORIAL TROUGH ON FRIDAY WILL BRING A FEW MORE
SHOWERS TO THE REPUBLIC. CHUUK STATE HAS BEEN FEELING THE EFFECTS
OF A CIRCULATION TO THE SOUTHEAST WITH UP TO 5 INCHES OF RAIN IN
SOME AREAS TODAY. A DRIER PATTERN WILL FALL INTO PLACE OVERNIGHT
AND CONTINUING THROUGH THE WEEKEND AS THE CIRCULATION EXITS CHUUK
WATERS TOWARDS THE WEST.

&&

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

$$

ZIOBRO/M. AYDLETT







000
FXPQ60 PGUM 222231
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
831 AM CHST WED APR 23 2014

.MARIANAS SYNOPSIS...
THE PGUA WSR-88D SHOWS ALMOST NO SHOWER ACTIVITY WITHIN THE
MARIANAS COASTAL WATERS. IR SATELLITE SHOWS A TROPICAL DISTURBANCE
SOUTHEAST OF GUAM. THE FAR NORTHERN SHOWERS COULD END UP AFFECTING
THE ZONES OVER THE WEEKEND. THE VAD WIND PROFILE REVEALS EAST-
NORTHEAST WINDS OF 12 TO 19 KNOTS THROUGH THE LOWEST 5 THOUSAND
FEET OF THE AIR.

&&

.DISCUSSION...
FARTHEST NORTH BOUND OF SHOWERS ASSOCIATED WITH THE TROPICAL
DISTURBANCE HAS BEEN DEVELOPING FARTHER TO THE NORTH. IF THIS
TREND CONTINUES...SCATTERED SHOWERS WILL MOST LIKELY BE ADDED TO
THE FORECAST EITHER LATER TODAY OR EARLY THURSDAY. MODEL AGREEMENT
IS SLOWLY GETTING BETTER...SO CONFIDENCE IS GRADUALLY INCREASING.
THE GFS40 IS NOW HANGING UP THE SHEAR LINE TO THE NORTHWEST OF THE
MARIANAS IS THE SINGLE BIGGEST CHANGE THAT HAS CAUSED THE
IMPROVEMENT. NO SIGNIFICANT CHANGES TO THE GRIDS.

&&

.EASTERN MICRONESIA...
THE NEAR-EQUATORIAL TROUGH REMAINS ACTIVE OVER EASTERN
MICRONESIA. A WEAK CIRCULATION ALONG THE TROUGH IS CENTERED
SOUTHWEST OF POHNPEI NEAR 5N156E. THIS DISTURBANCE IS GENERATING
A LARGE AREA OF CONVECTION OVER POHNPEI AND KOSRAE STATES.
SCATTERED SHOWERS ARE LIKELY THROUGH THE DAY AT POHNPEI AND
KOSRAE...BUT WILL GRADUALLY DECREASE AT KOSRAE THIS EVENING AND
AT POHNPEI THURSDAY AS THE DISTURBANCE SLOWLY DRIFTS WESTWARD.
MODELS STILL INDICATE THE TROUGH WILL REMAIN OVER THE
REGION...KEEPING KOSRAE AND POHNPEI IN AN OVERALL ACTIVE UNSTABLE
PATTERN THROUGH THE WEEKEND...THOUGH THUNDERSTORMS ARE LESS
LIKELY AT POHNPEI SATURDAY. TRADE WINDS PUSHING INTO THE
MARSHALLS BROUGHT DRIER CONDITIONS TO MAJURO OVERNIGHT. THOUGH
THE OVERALL PATTERN WILL REMAIN UNSTABLE INTO THE WEEKEND...
OVERALL DRIER CONDITIONS ARE EXPECTED. ANOTHER CONVERGENCE PATTERN
IS LIKELY TO DEVELOP NEAR THE MARSHALLS THIS WEEKEND... BRINGING
AN INCREASE IN CONVECTION BACK TO MAJURO FOR THE WEEKEND.
MAINTAINED INHERITED FORECAST FOR ISOLATED SHOWERS FOR NOW...BUT
AS THE PATTERN DEVELOPS AND POSITION IS BETTER DEFINED...
SCATTERED SHOWERS MAY BE A POSSIBILITY.

&&

.WESTERN MICRONESIA...
YAP AND KOROR BEGIN THE DAY WITH PREVAILING DRY CONDITIONS.
APPROACHING SHOWERS AND THUNDERSTORMS LOOK TO PUSH JUST SOUTH OF
KOROR TODAY BUT WILL BE CLOSE ENOUGH THAT KOROR MAY SEE A SHOWER
OR TWO AND POSSIBLY A THUNDERSTORMS OVER THE SOUTHERN WATERS.
OTHERWISE...KEPT YAP AND KOROR FORECAST FAIRLY DRY THROUGH THE
WEEKEND. FOR CHUUK...A WEAK CIRCULATION CENTERED SOUTHWEST OF
POHNPEI NEAR 5N156E HAS HELPED KICK UP SCATTERED SHOWERS AND SOME
THUNDERSTORMS OVER THE STATE. THE GFS AND ECMWF ARE IN FAIRLY
GOOD AGREEMENT THAT THIS DISTURBANCE WILL DEVELOP OVER THE NEXT
FEW DAYS AND MOVE TOWARD THE NORTHWEST BUT THEY VARY SLIGHTLY ON
POSITION. BASICALLY...THIS DISTURBANCE WILL MAINTAIN AN ACTIVE
PATTERN OVER CHUUK THROUGH THURSDAY WITH DRIER CONDITIONS PUSHING
INTO THE REGION BEHIND THE EXITING DISTURBANCE. AS THIS SYSTEM
DEVELOPS OVER THE NEXT DAY OR TWO...THE CIRCULATION MAY APPROACH
CLOSE TO ENOUGH TO YAP AND KOROR TO INCREASE SHOWERS AT BOTH
LOCATIONS OVER THE WEEKEND.

&&

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

$$

STANKO/KLEESCHULTE







000
FXPQ60 PGUM 220610
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
410 PM CHST TUE APR 22 2014

.MARIANAS SYNOPSIS...
SATELLITE AND RADAR IMAGERY SHOW THAT DRIER CONDITIONS HAVE
PUNCHED BACK INTO THE MARIANAS. A FEW SHOWERS ARE SEEN JUST
ENTERING THE MARINE ZONES TO THE EAST BUT THESE SHOWERS WILL BE
SHORT-LIVED AND PASS QUICKLY THROUGH THE AREA.

&&

.DISCUSSION...
NOT MUCH CHANGE MADE TO THE FORECAST. YESTERDAY...MODELS BRIEFLY
SHOWED THE CIRCULATION NEAR KOSRAE OPENING UP INTO A SURFACE
TROUGH WITH ANOTHER WEAK CIRCULATION FORMING FARTHER TO THE
SOUTHWEST...CLOSER TO THE EQUATOR AS THE BROADER SYSTEM OF SHOWERS
AND THUNDERSTORMS SLOWLY MOVES WESTWARD. THIS SEEMS TO BE THE
CASE. LATEST SURFACE ANALYSIS SHOWS A WEAK LOW-LEVEL CIRCULATION
CENTERED WELL SOUTH OF CHUUK NEAR 1N152E WITH CONVECTION FARTHER
DISPLACED TO THE NORTHEAST NEAR CHUUK AND POHNPEI ALONG THE
NORTHEAST-EXTENDING SURFACE TROUGH. COMPARED TO YESTERDAY`S MODEL
RUNS...MODELS ARE COMING INTO SLIGHTLY BETTER AGREEMENT AT LEAST
THROUGH SATURDAY. GFS IS CLOSER ALIGNED TO ECMWF WHICH PUSHES THE
SYSTEM WESTWARD JUST SOUTH OF GUAM AND THEN STALLS IT BETWEEN YAP
AND GUAM. THIS WOULD TEND TO FAVOR A WETTER FORECAST FOR THE
FRIDAY-SUNDAY TIME FRAME. BEYOND SATURDAY...EACH THE GFS40...GFS-
ENSEMBLE AND ECMWF SHOW THE CIRCULATION AND SURFACE TROUGH
INTERACTING WITH A PASSING FRONTAL SYSTEM NORTH OF THE CNMI. THIS
STILL LEADS TO A FAIR BIT OF UNCERTAINTY FROM SUNDAY ON. FOR EARLY
NEXT WEEK...THE MODELS FAVOR A SIMILAR LARGER-SCALE PATTERN OF A
WEAK CIRCULATION NEAR MINDANAO WITH A SURFACE TROUGH EXTENDING
EAST-NORTHEASTWARD ACROSS THE MARIANAS AND INTO A FRONTAL SYSTEM
NORTHWEST OF WAKE ISLAND. SHOULD THIS PAN OUT AS THE MODELS
SHOW...THIS PERIOD OF UNSETTLED CONDITIONS COULD PERSIST INTO
MIDDLE OF NEXT WEEK.

&&

.MARINE...
LITTLE CHANGE TO GRIDS. ADJUSTED SEAS DOWN ABOUT A FOOT TO MORE
CLOSELY ALIGN TO LOCAL BUOYS IN SHOWING SEAS OF 4 TO 5 FEET.
OTHERWISE...SEAS WILL BUILD TO BETWEEN 5 AND 7 FEET BY WEDNESDAY
NIGHT. MODELS STILL INDICATE A BUILDING NORTH SWELL OVER THE
WEEKEND THAT COULD PUSH SURF ALONG NORTH-FACING REEFS TO HAZARDOUS
LEVELS.

&&

.EASTERN MICRONESIA...
MORNING SHOWERS AT KOSRAE DISSIPATED BY NOON LEAVING DEBRIS CLOUDS
ACROSS POHNPEI AND KOSRAE. THE EASTERN END OF THE NEAR-EQUATORIAL
TROUGH THOUGH IS BEGINNING TO FIRE BACK UP THIS AFTERNOON. ISOLATED
SHOWERS AND THUNDERSTORMS ARE PRESENT ACROSS MUCH OF POHNPEI AND
KOSRAE STATES. HOWEVER...SCATTERED SHOWERS ARE SEEN JUST WEST AND
NORTH OF POHNPEI...AND OVER KOSRAE. MOST MODELS SHOW THE CONVECTION
AT POHNPEI SHOULD STAY JUST TO THE NORTH AND WEST...HOWEVER GFS
SHOWS A BUILD UP OF SHOWERS OVER THE ISLAND TONIGHT. IF THIS
HAPPENS...FORECAST MAY NEED TO BE UPDATED FOR SCATTERED SHOWERS
OVERNIGHT. MODELS DO SHOW MORE ALIGNMENT INDICATING SCATTERED
SHOWERS TOMORROW AT POHNPEI. A LARGER AREA OF SHOWERS AND
THUNDERSTORMS IS SEEN NEAR MAJURO. SCATTERED SHOWERS WILL REACH
MAJURO LATER THIS EVENING. MODELS INDICATE THESE SHOWERS WILL
EVENTUALLY SLIDE TO THE SOUTH WITH DRIER CONDITIONS AT MAJURO FOR
THE REMAINDER OF THE WEEK. A GENERALLY UNSETTLED BUT DRIER PATTERN
IS EXPECTED THROUGH THE END OF THE WEEK ACROSS THE REGION AS
TRADES BUILD IN. A SHOWERY CONVERGENCE ZONE IS EXPECTED TO DEVELOP
SOUTH OF MAJURO ON SUNDAY...GRADUALLY LIFTING TOWARDS THE
NORTHWEST BY SUNDAY. THIS WILL BRING MORE SHOWERS TO THE REGION
THEN.

&&

.WESTERN MICRONESIA...
DRY CONDITIONS PERSIST AT YAP AND KOROR THIS EVENING...HOWEVER
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER CHUUK. CONVERGENCE
ALONG THE NORTHERN EDGE OF THE NEAR-EQ TROUGH JUST SOUTH OF CHUUK
WILL GENERATE SHOWERS AND THUNDERSTORMS THROUGH THE NIGHT THERE.
ADDED IN ISOLATED THUNDERSTORMS TO CHUUK FORECAST FOR WEDNESDAY.
MODELS SHOW THIS MOISTURE WILL GRADUALLY LIFT TOWARDS THE NORTHWEST
THROUGH WEDNESDAY ALLOWING DRIER CONDITIONS TO DEVELOP BY WEDNESDAY
NIGHT AND THURSDAY. FARTHER WEST...DRIER WEATHER WILL PERSIST AT YAP
AND KOROR THE NEXT FEW DAYS. VIS SATELLITE SHOWS SOME SPOTTY
CONVECTION OVER YAP SO ADDED IN A SLIGHT CHANCE OF THUNDERSTORMS
THERE OVERNIGHT. LONG-TERM FORECAST IS A BIT UNCERTAIN BASED ON THE
FUTURE TRACK AND EVOLUTION OF A WEAK CIRCULATION WITHIN THE NEAR-EQ
TROUGH SOUTH OF CHUUK AND POHNPEI. MODELS GENERALLY AGREE IN SHOWING
A CIRCULATION SLOWLY DEVELOPING AS IT HEADS WEST-NORTHWEST THE NEXT
FEW DAYS TOWARDS YAP...BUT EVENTUALLY TURNING TOWARDS THE NORTH OVER
THE MARIANAS. IF THE CIRCULATION COMES CLOSER TO YAP AND OR KOROR
LATER THIS WEEKEND...BOTH LOCATIONS COULD SEE MORE SHOWERS.

&&

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

$$

W. AYDLETT/M. AYDLETT









000
FXPQ60 PGUM 212232
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
832 AM CHST TUE APR 22 2014

.MARIANAS SYNOPSIS...
PGUA WSR-88D SHOWS ALMOST NO SHOWERS WITHIN THE MARIANAS COASTAL
WATERS. THE VAD WIND PROFILE REVEALS EAST-SOUTHEAST WINDS OF 12 TO
19 KNOTS THROUGH THE LOWEST 5 THOUSAND FEET OF THE AIR.

&&

.DISCUSSION...
LITTLE CHANGE TO PREVIOUS FORECAST. WHILE BOTH THE GFS40 AND
ECMWF-HIRES INDICATE MOISTER TIMES AHEAD...THEY COME ABOUT THAT
SIMILAR ANSWER IN DISTURBINGLY DIFFERENT WAYS. THIS LED TO LOW
CONFIDENCE IN THE ACTUAL FUTURE DEVELOPMENT OF FEATURES. THE GFS40
BRINGS DOWN AN UNSEASONABLY LATE SHEAR LINE. THE ECMWF-HIRES
BRINGS A PASSING TROPICAL DISTURBANCE FARTHER TO THE NORTH. BEFORE
MAKING TOO MANY CHANGES...WANT TO SEE SOME BETTER AGREEMENT. FOR
NOW...JUST EXTENDED THE THUNDERSTORMS INTO MONDAY AS THE MODELS
SIGNAL THIS INCREASE MOISTURE COULD LAST AT LEAST THAT LONG.

WAVES WILL RISE AS THE WEEK PROGRESSES...ESPECIALLY NEAR THE
WEEKEND. A HIGH SURF ADVISORY LOOKS LIKELY...A SMALL CRAFT
ADVISORY WOULD BE PRETTY MARGINAL. NEED TO GIVE IT A LITTLE MORE
TIME THOUGH AS THIS IS AT LEAST 3 DAYS AWAY IN ANY CASE.

&&

.EASTERN MICRONESIA...
SOME CHANGES NEEDED IN THE SHORT TERM...MAINLY FOR KOSRAE AND
POHNPEI. ISOLATED SHOWERS REMAIN OVER POHNPEI THIS MORNING WITH
SCATTERED SHOWERS FOUND A LITTLE FARTHER EAST OVER KOSRAE. THESE
SHOWERS ARE EXPECTED TO DRIFT WESTWARD THROUGH THE DAY...KEEPING
SCATTERED SHOWERS OVER KOSRAE A LITTLE LONGER AND DELAYING
SCATTERED SHOWERS OVER POHNPEI UNTIL THIS AFTERNOON. A WEAK
DISTURBANCE CENTERED SOUTH OF KOSRAE ALONG WITH THE NEAR-
EQUATORIAL TROUGH WILL HELP TO MAINTAIN AN UNSETTLED PATTERN OVER
THE REGION THROUGH THE WEEK. LATEST MODEL RUN KEEPS SHOWERS AND AN
UNSTABLE PATTERN OVER KOSRAE AND POHNPEI THROUGH SATURDAY WITH A
DRIER PATTERN MOVING IN OVER MAJURO BEGINNING TODAY...WITH PARTLY
CLOUDY CONDITIONS EXPECTED BY THE WEEKEND.

&&

.WESTERN MICRONESIA...
FAIR CONDITIONS CONTINUE ACROSS WESTERN MICRONESIA THIS MORNING. A
LINE OF SHOWERS AND ISOLATED THUNDERSTORMS HAS DEVELOPED TO THE
SOUTHWEST OF YAP ALONG THE CONVERGENCE ZONE TO THE NORTHEAST OF THE
NEAR-EQUATORIAL TROUGH. THESE SHOWERS LOOK TO DRIFT SLOWLY
WESTWARD...REMAINING TO THE SOUTH OF YAP. A WEAK DISTURBANCE ALONG
THE TROUGH...CURRENTLY CENTERED SOUTH OF KOSRAE...IS PROGGED TO MOVE
TO THE NORTHWEST. THIS WOULD BRING THE CIRCULATION TO JUST SOUTH OF
GUAM. IF THIS OCCURS...THE DISTURBANCE WILL DRAG THE NEAR-EQUATORIAL
TROUGH FURTHER NORTHWARD AND COULD WELL BRING AN INCREASE IN SHOWERS
TO PALAU FOR THE LATTER PART OF THE WEEK. CHOSE TO CONTINUE WITH THE
INHERITED FORECAST FOR NOW AND WAIT TO SEE IF THIS IS LIKELY TO
HAPPEN. SCATTERED SHOWERS TO THE EAST OF CHUUK LOOK TO BE MOVING IN
A BIT FASTER THAN EXPECTED...SO ADDED WORDING TO BRING SCATTERED
SHOWERS INTO CHUUK THIS AFTERNOON AND CONTINUE THROUGH TONIGHT.
OTHERWISE...NO CHANGES TO THE INHERITED FORECAST.

&&

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

$$

STANKO/KLEESCHULTE







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