WPAC: INVEST 98W

[ManilaTC]

BEST TRACK: 98W INVEST 140722 0600 2.2N 148.4E WPAC 15 NA

[ManilaTC]

SATELLITE INTERPRETATION MESSAGE
NATIONAL WEATHER SERVICE TIYAN GU
100 PM CHST TUE JUL 22 2014

WESTERN NORTH PACIFIC BETWEEN EQUATOR AND 25N FROM 130E TO 180.

A MONSOON TROUGH EXTENDS SOUTHEASTWARD FROM 16N130E THROUGH A
TROPICAL DISTURBANCE CENTERED WEST OF GUAM NEAR 12N140E TO A
CIRCULATION CENTERED SOUTHWEST OF CHUUK AT 2N150E...

=======================

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
502 PM CHST TUE JUL 22 2014

.MARIANAS SYNOPSIS...
VISIBLE SATELLITE SHOWS ISOLATED THUNDERSTORMS OUT EAST OF THE
ISLANDS...ASSOCIATED WITH AN UPPER-LEVEL TROUGH THAT EXTENDS FROM
12N146E NORTHEASTWARD TO BEYOND 18N157E. SATELLITE ALSO SHOWS
TROPICAL DISTURBANCES NORTH OF YAP NEAR 13N139E AND SOUTHWEST OF
CHUUK NEAR 3N149E. ISOLATED SHOWERS AND GENTLE TRADES ARE FOUND IN
THE MARIANAS WATERS.

.DISCUSSION...
ONLY SIGNIFICANT CHANGE FROM THE PREVIOUS FORECAST IS TO BRING IN
MOSTLY CLOUDY WITH ISOLATED SHOWERS AND THUNDERSTORMS LATE TONIGHT
AND WEDNESDAY AS THE UPPER TROUGH MOVES WEST OVER THE ISLANDS ON
WEDNESDAY. HAVE ALSO DELAYED THE ARRIVAL OF ISOLATED THUNDERSTORMS
LATER THIS WEEK TO FRI NIGHT...AS GFS HAS SLOWED THE DEVELOPMENT
OF THE CHUUK DISTURBANCE. INDEED...THIS DISTURBANCE IS THE MAIN
FORECAST ISSUE FOR THE NEXT FEW DAYS. THE GFS DEVELOPS IT INTO A
30-35 KT CIRCULATION AS IT BRINGS IT OVER GUAM EARLY SATURDAY
MORNING...WHILE THE ECMWF MERELY BRINGS THE MONSOON TROUGH NORTH
INTO THE MARIANAS ON SATURDAY--WITHOUT ANY CIRCULATIONS. BOTH
MODELS WOULD BRING THE POSSIBILITY OF HEAVY RAIN FRI NIGHT THROUGH
SATURDAY...BUT THE GFS VERSION WOULD CERTAINLY BRING MUCH STRONGER
WINDS AND HIGHER SEAS THAN THE ECMWF. FOR NOW HAVE LEANED MORE ON
THE ECMWF...AS ITS SCENARIO IS MUCH MORE LIKELY THAN DRAGGING A
QUICKLY-DEVELOPED CIRCULATION INTO GUAM FROM THE SSE. IN ANY
CASE...STILL NOT CONVINCED ENOUGH EVEN BY THE ECMWF TO UPGRADE TO
SCATTERED SHOWERS FOR FRI NIGHT OR SATURDAY...NOT UNTIL WE HAVE
VISIBLE INDICATIONS ON SATELLITE OF SOMETHING TANGIBLE ACTUALLY
COMING OUR WAY.

[euro6208]

This is forecast to interact with Invest 96W. Now the question is, Which one will win and become the dominant circulation?

[euro6208]

I think this discussion is appropriate for this invest since it is moving towards Yap and Palau...

000
WWPQ80 PGUM 230023 CCA
SPSPQ

SPECIAL WEATHER STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE TIYAN GU
1023 AM CHST WED JUL 23 2014

PMZ161-171-240000-
KOROR PALAU-YAP-
1023 AM CHST WED JUL 23 2014

CORRECTED TYPO IN 2ND PARAGRAPH

...HEAVY SHOWERS AND GUSTY WINDS TO DEVELOP ACROSS PALAU AND YAP...

TWO TROPICAL DISTURBANCES...CENTERED NORTHWEST OF YAP NEAR 13N137E
AND SOUTH OF GUAM NEAR 7N146E...ARE EXPECTED TO SLOWLY DEVELOP OVER
THE NEXT FEW DAYS. SCATTERED TO NUMEROUS HEAVY SHOWERS AND ISOLATED
THUNDERSTORMS ARE POSSIBLE ACROSS THE THE REPUBLIC OF PALAU AND YAP
STATE THROUGH THE END OF THE WEEK...WITH 4 TO 7 INCHES OF RAIN
POSSIBLE. EXTENDED PERIODS OF HEAVY RAINFALL WILL RAISE THE RISK OF
MUDSLIDES ON KOROR.

WEST TO SOUTHWEST MONSOON WINDS WILL INCREASE FROM 10 TO 15 MPH
TODAY TO BETWEEN 20 AND 30 MPH BY THURSDAY ACROSS THE REPUBLIC OF
PALAU AND LATE FRIDAY ACROSS YAP STATE.

SEAS WILL BECOME HAZARDOUS FOR OPERATORS OF SMALL CRAFT IN YAP STATE
AND PALAU BY THE END OF THE WEEK. SUSTAINED WINDS OF 15 TO 25 KNOTS
WITH GUSTS UP TO 30 KNOTS NEAR HEAVIER SHOWERS ARE EXPECTED TO BRING
COMBINED SEAS TO BETWEEN 9 AND 11 FEET BY THE WEEKEND.

STAY INFORMED ON THIS WEATHER SITUATION...ESPECIALLY IF PLANNING
MARINE ACTIVITIES. LISTEN FOR UPDATES FROM THE NATIONAL WEATHER
SERVICE AND YOUR LOCAL WEATHER SERVICE AND EMERGENCY MANAGEMENT
OFFICES.

$$

AYDLETT/WILLIAMS/MGM

[euro6208]

Broad monsoon type depression developing and pressures falling throughout the region...Currently 3 invest in this mess. Which one will win out?

NWS Guam...

THE REAL QUESTION IS WHAT WILL HAPPEN TO THE CIRCULATION SOUTH OF
CHUUK LOCATED ON SCATTEROMETER DATA LAST NIGHT NEAR 5N150E.
MODELS STILL PREDICT THAT IT WILL INTERACT WITH THE CIRCULATION
JUST NORTH OF YAP. THE CHUUK CIRCULATION ALREADY BIG WILL BECOME
LARGER BY MERGING WITH THE YAP CIRCULATION. THE RESULTING
CIRCULATION WILL BECOME A LARGE MONSOON TYPE LOW PRESSURE SYSTEM
IN THE PHILIPPINE SEA WEST OF GUAM THIS WEEKEND.

AN INTERESTING OBSERVATION IS THE CHANGE OF SEA LEVEL PRESSURE
ACROSS MICRONESIA DURING THE MORNING HOURS SEA LEVEL PRESSURE WAS
DECREASING ACROSS THE WHOLE REGION. USUALLY THIS IS SEEN AT ONE
OR TWO STATIONS...BUT NOT SO OFTEN ACROSS A WHOLE REGION. IF THIS
PATTERN PERSIST THAN THE MODELS WILL PROBABLY BE RIGHT IN
PREDICTING THE DEVELOPMENT OF THE LARGE MONSOON TYPE LOW. WHAT
DOES THIS MEAN FOR THE MARIANAS. MODELS STILL HAVE NOT AGREED ON
THE DETAILS. SOME SHOW AN AREA OF STRONGER WINDS AROUND THE
PERIPHERY OF THE LOW OVER PALAU AND YAP. GFS HOWEVER BRING
STRONGER WINDS OVER THE MARIANAS THIS WEEKEND. HAVE NOT CHANGE
THE WIND FORECAST YET AS CERTAINTY ON THIS FACT IS LOW.
CONFIDENCE IS HIGHER IN THE RAINFALL DEPARTMENT OF THE FORECAST.
NO MATTER WHAT THE LARGE CIRCULATION DOES...MODELS AGREE ON IT
DRAGGING THE MONSOON TROUGH ACROSS THE MARIANAS THIS WEEKEND. THE
TROUGH WILL BE ASSOCIATED WITH DEEP MOISTURE WHICH WILL EQUAL A
FAIR CHANCE OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THIS
WEEKEND. HAVE UPDATED THE FORECAST TO REFLECT THIS.

[euro6208]

Monsoon depression...

[euro6208]

Interesting 06Z.

One of twin typhoons developing and quite strong...Another taiwan landfall?

[euro6208]

98W INVEST 140723 1200 8.0N 147.2E WPAC 15 1010

Very disorganized...

[euro6208]

000
WWPQ80 PGUM 240019
SPSPQ

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TIYAN GU
1019 AM CHST THU JUL 24 2014

PMZ161-171-172-250200-
KOROR PALAU-YAP-CHUUK-
1019 AM CHST THU JUL 24 2014

...INCLEMENT WEATHER DEVELOPING NEAR CHUUK AND POSSIBLE FOR YAP
AND PALAU...

TWO TROPICAL DISTURBANCES EMBEDDED WITHIN A MONSOON TROUGH ARE
CENTERED NORTHWEST OF KOROR IN THE REPUBLIC OF PALAU NEAR 10N137E...
AND WEST OF WENO ISLAND IN CHUUK STATE NEAR 7N149E. AS THESE SYSTEMS
SLOWLY DEVELOP...THEY ARE EXPECTED TO INTRODUCE A WET MONSOONAL
PATTERN ACROSS WESTERN MICRONESIA OVER THE NEXT SEVERAL DAYS.
SCATTERED HEAVY SHOWERS AND ISOLATED THUNDERSTORMS ARE ALREADY
FLARING UP NEAR LUKUNOR ATOLL IN CHUUK STATE THIS MORNING. LATEST
SATELLITE DERIVED WIND DATA ALSO REVEAL 15 TO 25 MPH WEST TO
SOUTHWEST MONSOON WINDS NEAR THE DISTURBANCE IN CHUUK STATE.

THESE HEAVY SHOWERS AND MONSOON WINDS ARE GOING TO SPREAD NORTHWARD
OVER THE REST OF CHUUK STATE LATER THIS EVENING. RAINFALL OF 3 TO 5
INCHES IS PROBABLE ACROSS CHUUK STATE BY SATURDAY. THESE SAME
CONDITIONS COULD ALSO DEVELOP ACROSS YAP STATE AND THE REPUBLIC OF
PALAU BY THIS WEEKEND. IF THESE DISTURBANCES BECOME BETTER
ORGANIZED...HIGHER RAINFALL AND WINDS ARE POSSIBLE. EXTENDED PERIODS
OF HEAVY RAINFALL WOULD RAISE THE RISK OF MUDSLIDES ACROSS PALAU AND
FLOODING IN LOW LYING AREAS IN YAP AND CHUUK STATES.

SEAS OF 5 TO 7 FEET TODAY WILL RISE TO BETWEEN 8 AND 10 FEET IN
CHUUK STATE ON FRIDAY...AND ACROSS YAP STATE AND THE REPUBLIC OF
PALAU THIS WEEKEND. SEAS AT THESE HEIGHTS WILL BE HAZARDOUS FOR
OPERATORS OF SMALL CRAFT. SURF COULD ALSO BECOME HAZARDOUS FOR ALL
LOCATIONS BY THIS WEEKEND.

STAY INFORMED ON THIS WEATHER SITUATION...ESPECIALLY IF PLANNING
MARINE ACTIVITIES. LISTEN FOR UPDATES FROM THE NATIONAL WEATHER
SERVICE AND YOUR LOCAL WEATHER SERVICE AND EMERGENCY MANAGEMENT
OFFICES.

$$

CHAN

[euro6208]

Looks like a very large monsoon depression developing.

[euro6208]

ECMWF AND GFS REMAIN FAR APART...WITH THE GFS STILL SPINNING UP
A PAIR A TROPICAL STORMS OR TYPHOONS NORTH OF YAP AND CHUUK...WITH
THE CHUUK STORM TURNING NW THROUGH THE MARIANAS NORTH OF SAIPAN
AROUND THE MIDDLE OF NEXT WEEK. THE MORE CONSISTENT AND REALISTIC
ECMWF STILL DEVELOPS THE WESTERN SYSTEM WHILE LIFTING THE MONSOON
TROUGH SLOWLY NORTHWARD THROUGH THE MARIANAS OVER THE WEEKEND...AND
THIS IS THE BASIS OF THE FORECAST FOR THE NEXT WEEK. HAVE EXTENDED
SCATTERED SHOWERS THROUGH MONDAY NIGHT...AND ISOLATED THUNDERSTORMS
THROUGH WEDNESDAY NIGHT. OF COURSE...WITH SUCH DISAGREEMENT
BETWEEN THE MODELS...FORECAST CONFIDENCE IN WINDS AND SEAS IS
RATHER LOW. IF A STRONG TROPICAL CYCLONE DOES INDEED FORM NORTH OF
CHUUK AS DEPICTED BY THE GFS...WINDS AND SEAS COULD BE MUCH HIGHER
THAN CURRENTLY FORECAST LATE THIS WEEKEND INTO NEXT WEEK.
CONFIDENCE IN THE RAIN FORECAST IS SOMEWHAT HIGHER...AS BOTH MODELS
WOULD BRING UP TO 7 INCHES OF RAIN BY NEXT WEDNESDAY.

[euro6208]

Nakri east of Guam



Hits the Northern Islands



Peak...

[euro6208]

NWS Guam:

FOR CHUUK...POHNPEI AND KOSRAE STATES...

WEATHER WILL BE UNSTABLE FOR LARGE AREAS OF MICRONESIA. SOUTHWEST TO
WEST MONSOON WINDS OF 10 TO 20 MPH AND LOCALLY HEAVY SHOWERS ARE
EXPECTED THIS WEEKEND. SEA CONDITIONS WILL BE HAZARDOUS AT TIMES FOR
OPERATORS OF SMALL BOATS AND HAZARDOUS SURF WILL LIKELY REQUIRE SURF
ADVISORIES FOR SOME LOCATIONS. COMBINED SEAS WILL RANGE FROM 5 TO 8
FEET BUT WILL APPROACH 10 FEET IN STRONG WIND GUSTS NEAR SHOWERS AND
THUNDERSTORMS. RAINFALL COULD BE HEAVY AT TIMES WITH FLOODING OF
RIVERS AND LOW LYING AREAS. THE RISK OF MUDSLIDES COULD DEVELOP ON
THE HIGHER ISLANDS THIS WEEKEND.

[ManilaTC]

I believe the 2nd storm will not spawn out of this disturbance, it will be one much farther east around 155-160E.

Best track no longer updates 98W though.

[ManilaTC]

The NRL TC page and the NOAA RAMMB CIRA pages no longer carry this disturbance and appears that 96W has won out as the dominant circulation.