Area Forecast Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
000
FXPQ60 PGUM 162030
AFDPQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
630 AM CHST WED SEP 17 2014

.MARIANAS SYNOPSIS...
RADAR SHOWS AREAS OF RAIN AND ISOLATED EMBEDDED THUNDERSTORMS ACROSS
THE COVERAGE AREA. SATELLITE SHOWS AREAS OF DEEP CONVECTION OVER THE
FORECAST ZONES. ASCAT ANALYSIS INDICATES THE CIRCULATION ASSOCIATED
WITH INVEST AREA 96W IS NEAR 12N137E AND DRIFTING TOWARD THE WEST.
VAD GRADIENT WINDS ARE SOUTH-SOUTHWEST AT 10 TO 15 KT. LOCAL BUOYS
SHOW COMBINED SEAS OF 4 TO 5 FEET WITH MIXED DIRECTIONAL COMPONENTS
FROM SOUTHWEST...EAST-NORTHEAST AND SOUTH.

&&

.DISCUSSION...
THE WET MONSOON-TYPE WEATHER WILL PERSIST TODAY AS INVEST AREA 96W
GRADUALLY DEVELOPS AND DRIFTS AWAY WESTWARD AND THEN NORTHWESTWARD.
RAINFALL WILL BE HEAVY TODAY FOR SOME LOCATIONS...ESPECIALLY NEAR
ROTA THIS MORNING. MOST MODELS INDICATE RELATIVELY DRIER WEATHER
WILL ARRIVE BY TONIGHT WITH A LIGHT WIND REGIME DEVELOPING THROUGH
THE WEEKEND.

&&

.MARINE...
SEA CONDITIONS WILL BE MIXED NEXT FEW DAYS WITH MODERATE RIP CURRENT
RISK ALONG MOST REEFS. ADJUSTMENTS WERE MADE TO WAVE GRIDS BASED ON
THE WW3 WAVE MODEL WHICH INDICATES SEVERAL DIFFERENT SMALLISH SWELL
COMPONENTS WILL AFFECT SEA CONDITIONS BESIDES THE BASIC E-NE AND SW
SWELLS ALREADY IN THE FORECAST. REFRESHED WIND GRIDS WITH LATEST GFS
MODEL DATA.

&&

.EASTERN MICRONESIA...
AN MCS DEVELOPED OVERNIGHT AT MAJURO PRODUCING SHOWERS AND A FEW
THUNDERSTORMS FOR MUCH OF THE NIGHTTIME HOURS REQUIRING A FORECAST
UPDATE. OVER 4 INCHES OF RAIN HAS FALLEN SO FAR THIS MORNING. A
FEW MORE SHOWERS ARE SEEN NEAR KOSRAE AND POHNPEI ALONG SURFACE
TROUGHS NEAR BOTH LOCATIONS. SCATTERED SHOWERS AT KOSRAE AND
MAJURO THIS MORNING WILL BECOME ISOLATED AROUND NOON TODAY AS
WEATHER GRADUALLY IMPROVES. GFS STILL SHOWS A DRYING TREND OVER
THE NEXT 24 HOURS ACROSS THE REGION AS THE BROAD TROUGH OVER THE
MARSHALL ISLANDS SHIFTS WEST. AM HESITANT TO FOLLOW THIS TREND
CONSIDERING THE SHOWERY WEATHER OVER THE LAST 24 TO 36 HOURS. WILL
MEET HALFWAY MAINTAINING MOSTLY CLOUDY SKIES AND ISOLATED SHOWERS
AND THUNDERSTORMS AT LEAST THROUGH THURSDAY NIGHT AT BOTH MAJURO
AND KOSRAE. WEATHER APPEARS TO BE A BIT MORE BENIGN AT POHNPEI IN
THE NEAR TERM. DAY SHIFT WILL HAVE TO CLOSELY WATCH HERE AS WELL
DUE TO THE PROXIMITY OF A SURFACE TROUGH. BY FRIDAY...MODELS SHOW
A BROAD MONSOON-TYPE TROUGH DEVELOPING ALONG 10N BRINGING WINDS AT
ALL LOCATIONS TO SOUTH OR SOUTHWEST. ADDITIONALLY...A WETTER
PATTERN IS PROGGED TO BEGIN WITH THIS FEATURE. WILL HAVE TO WATCH
HOW THIS EVOLVES THE NEXT FEW DAYS FOR A FINER-TUNED FORECAST.

&&

.WESTERN MICRONESIA...
DRY WEATHER REMAINS IN PLACE AT CHUUK THIS MORNING. IR SATELLITE
SHOWS ISOLATED SHOWERS AND THUNDERSTORMS NEAR POHNPEI THAT WILL
REACH CHUUK TONIGHT AND CONTINUE THROUGH THURSDAY NIGHT. DRIER
WEATHER WILL RETURN FOR THE END OF THE WEEK. AS MENTIONED IN THE
EASTERN DISCUSSION...A MONSOON-TYPE PATTERN IS PROGGED TO DEVELOP
BY SATURDAY ALONG 10N. WILL HAVE TO WAIT A FEW MORE DAYS TO SEE
HOW IT INFLUENCES THE WEATHER.

THE BROAD MONSOON CIRCULATION IS CENTERED NORTH-NORTHWEST OF YAP
NEAR 14N136E. THIS CIRCULATION IS NOW THE SUBJECT OF A TROPICAL
CYCLONE FORMATION ALERT BY THE JOINT TYPHOON WARNING CENTER.
SCATTERED SHOWERS ARE GRADUALLY PULLING AWAY FROM YAP AND KOROR
WITH THE BULK OF THE WEATHER NOW NORTHWEST OF BOTH LOCATIONS.
FORECAST REDUCES SHOWERS TO ISOLATED AROUND NOON. HOWEVER...IR
SATELLITE SHOWS A CLUSTER OF SHOWERS WEST OF YAP BETWEEN 140E AND
145E. THIS IS SLOWLY CREEPING WEST. GFS PICKS UP ON THIS...SHOWING
SHOWERS SLOWLY SUBSIDING BY AFTERNOON WITH THIS FEATURE. DAY SHIFT
WILL HAVE TO KEEP A WATCH ON THIS TO SEE THAT THIS HAPPENS
ACCORDING TO THE FORECAST. CONDITIONS WILL CONTINUE TO DRY OUT
THROUGH THURSDAY AND FRIDAY. WEEKEND FORECAST FOR BOTH YAP AND
KOROR LOOKS ERRATIC IN THE MODELS WITH LIGHT AND VARIABLE WIND
FLOWS...BUT GENERALLY DRY.

DAY SHIFT WILL ALSO HAVE TO KEEP A WATCH ON SEA HEIGHTS NEAR KOROR
AND YAP. AS THE MONSOON CIRCULATION GRADUALLY STRENGTHENS...WINDS
WILL MAINTAIN HIGHER SWELL ACROSS THE REGION.

&&

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

$$

SIMPSON/M. AYDLETT




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.