Area Forecast Discussion
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FXPQ60 PGUM 292050
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
650 AM CHST TUE JUN 30 2015

.SYNOPSIS...
PGUA WSR88D SHOWS ISOLATED SHOWERS ACROSS THE MARIANAS THIS
MORNING. GENTLE TO MODERATE TRADE WINDS PREVAIL NORTH OF 10N.
LATEST IR SATELLITE DATA SHOWS AN ACTIVE MONSOON TROUGH STRETCHING
ACROSS MICRONESIA...SOUTH OF 10N...WITH A SERIES OF FIVE WEAK
CIRCULATIONS ALONG THE TROUGH.

&&

.DISCUSSION...
A HIGH DEGREE OF UNCERTAINTY CONTINUES TO HAUNT THE MARIANAS
FORECAST FOR THE WEEKEND INTO NEXT WEEK. A VERY ACTIVE MONSOON
TROUGH STRETCHES ACROSS MICRONESIA AND IS AFFECTING ALL OF THE
FEDERATED STATES OF MICRONESIA...THE REPUBLIC OF PALAU AND THE
REPUBLIC OF THE MARSHALL ISLANDS. EACH MODEL STILL SHOWING ITS OWN
UNIQUE SOLUTION TO THE DEVELOPMENT...MOVEMENT AND INTENSITY OF
EACH OF THE CIRCULATIONS CURRENTLY IN PLACE ALONG THE MONSOON
TROUGH. BASED ON THE OVERALL CONSENSUS...IT LOOKS FAVORABLE FOR
INCREASING SHOWERS AND POSSIBLE THUNDERSTORMS OVER THE MARIANAS
FOR THE WEEKEND INTO THE EARLY PART OF NEXT WEEK. THE QUESTION
THAT STILL REMAINS IS...WHAT WILL ACTUALLY BE OVER GUAM AND THE
CNMI BY THE WEEKEND. MODEL SOLUTIONS INCLUDE EVERYTHING FROM A
TYPHOON TO A MONSOON SURGE. THEREFORE...CHOSE TO MAINTAIN THE
PREVIOUS FORECAST FOR NOW AS I CAN SEE NO BETTER SOLUTION AT THE
PRESENT TIME AND NO REASON TO CHANGE ANY PART OF THE INHERITED
FORECAST.

&&

.EASTERN MICRONESIA...
A COMPLEX WEATHER PATTERN CONTINUES TO EVOLVE ACROSS MICRONESIA FROM
CHUUK TO THE MARSHALL ISLANDS. JTWC INVEST 94W CONTINUES TO SPIN
WEST-NORTHWEST OF CHUUK AT 9N147E...WHILE 95W REMAINS NORTH-
NORTHWEST OF KOSRAE AT 10N161E. HEAVIEST WEATHER THIS MORNING IS
JUST SOUTH OF 94W AND WEST OF CHUUK...AND NEAR POHNPEI JUST WEST OF
95W. ISOLATED TO SCATTERED SHOWERS ARE SEEN ELSEWHERE ACROSS THE
REGION. BURST OF FRESH TO STRONG WEST WINDS ARE SEEN IN THE 12Z
ASCAT PASS NEAR AND SOUTH OF CHUUK...POHNPEI...KOSRAE AND MAJURO.
THESE RAIN AND WIND CONDITIONS WILL PERSIST THE NEXT COUPLE DAYS
WHILE THE MONSOON TROUGH MEANDERS IN PLACE. THIS TROUGH WILL SLOWLY
LIFT TOWARDS THE WEST OR NORTHWEST LATER THIS WEEK AS 94W AND 95W
EVOLVE. MODELS STILL SHOW A WIDE RANGE OF POSSIBILITY WITH THESE
SYSTEMS THROUGH THE END OF THE WEEK. HOWEVER...MODELS DO EVENTUALLY
CONVERGE ON A BROADER...SINGLE CIRCULATION HEADING TOWARDS THE
MARIANAS BY THE WEEKEND WITH DRIER CONDITIONS IN ITS WAKE ACROSS THE
REGION. IN THE LONG TERM...SOME MODELS HINT AT ANOTHER CIRCULATION
PASSING NEAR OR JUST NORTH OF MAJURO WHICH COULD BRING MORE WEATHER
TO THE MARSHALLS FOR THE WEEKEND.

HIGH SURF ADVISORIES REMAIN IN EFFECT FOR KOSRAE AND POHNPEI... AND
MAY BE NEEDED FOR CHUUK AND EVEN MAJURO LATER THIS WEEK. SURGING
WESTERLY WINDS WILL CAUSE HAZARDOUS SURF AND SEA CONDITIONS FOR MUCH
OF MICRONESIA THIS WEEK...ESPECIALLY ON THE SOUTH SIDE OF THE
MONSOON TROUGH.

&&

.WESTERN MICRONESIA...
CHUUK DISCUSSION IS INCLUDED ABOVE WITH EASTERN MICRONESIA BECAUSE
OF SIMILAR WEATHER.

12Z ASCAT ANALYSIS SHOWS THE MONSOON TROUGH PASSING NORTH OF KOROR
AND YAP TO JTWC INVEST 94W AT 9N147E THIS MORNING. SOUTHWEST TO WEST
MONSOON WINDS ARE SURGING ACROSS THE REPUBLIC OF PALAU AND JUST
SOUTH OF YAP EASTWARD TOWARD EASTERN MICRONESIA. THE MODELS STILL
DIFFER SIGNIFICANTLY ABOUT DEVELOPMENTS WITH THE CIRCULATION WEST OF
CHUUK...AND IT WILL NEED TO BE MONITORED CLOSELY IN THE COMING DAYS.
LATEST MODEL GUIDANCE SUGGESTS A SLIGHTLY DRIER TREND IN THE NEAR
TERM FOR YAP AND LATE WEDNESDAY INTO THURSDAY FOR KOROR...BUT WETTER
WEATHER WILL RETURN AS THE MONSOON SURGES WITH A STRENGTHENING
SYSTEM IN EASTERN MICRONESIA. A CIRCULATION WITHIN THE TROUGH
NORTHWEST OF KOROR COULD HELP REINFORCE SOUTHWEST WINDS IN THE NEAR
TERM...BUT IS NOT EXPECTED TO GENERATE MUCH WEATHER AT KOROR OR YAP.
WILL MONITOR THIS FOR ANY CHANGES AND DEVELOPMENTS AS WELL.

HIGH SURF ADVISORY WAS ISSUED FOR KOROR AND A HIGH SURF ADVISORY MAY
BE NEEDED FOR YAP IN THE NEXT DAY OR TWO.

&&

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

$$

KLEESCHULTE/W. AYDLETT



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