Subject: Western Pacific: Synoptic Discussion For The Marianas

From: LDM Weather <[email-masked]>
Date: Wed, 24 Nov 2010 00:21:54 -0600

119 
FXPQ60 PGUM 240621
AFDPQ 

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
421 PM CHST WED NOV 24 2010

.SYNOPSIS...
RADAR IMAGERY SHOWS ISOLATED SHOWER COVERAGE. VISIBLE SATELLITE
SHOWS A WEAKENING TRADE-WIND DISTURBANCE APPROACHING THE FORECAST
ZONES. ASSOCIATED CONVECTION TILTS FROM SW TO NE. WATER VAPOR
SATELLITE IMAGERY STILL SHOWS TUTT AXIS LIES BETWEEN GUAM AND
CHUUK...WHICH PLACES THE MARIANAS BENEATH UPPER-LEVEL SUBSIDENCE.
BELIEVE TRADE- WIND DISTURBANCE WILL BRING A SLIGHT INCREASE IN
SHOWER COVERAGE LATER THIS EVENING AND TONIGHT...BUT RADAR AND
SATELLITE IMAGERY SUGGESTS POPS WILL REMAIN ISOLATED.

&&

.DISCUSSION...
GFS STILL REMAINS THE MOST BULLISH OF THE MODELS REGARDING THE
TRADE-WIND DISTURBANCE DUE IN LATER TONIGHT. HOWEVER...GFS HAS
BEEN TRENDING DOWNWARD WITH QPFS DURING THIS TIME FRAME...SO WILL
MAINTAIN ISOLATED POPS OVERNIGHT TONIGHT. DRYING TREND IS
EXPECTED ON THU AND FRI AS A TRADE-WIND REGIME ASSERTS ITSELF FOR
THE REMAINDER OF THE FORECAST PERIOD.

&&

.MARINE...
ASCAT AND WINDSAT IMAGERY SHOWS LONG FETCH OF NE GALES HAS
PERSISTED NORTH OF WAKE ISLAND FOR THE PAST 36 HOURS OR SO. 23
NOV ALTIMETRY SHOWED THE LEADING EDGE OF THE HIGHER SEAS ABOUT
500 MILES TO THE NE OF SAIPAN...SO AGREE WITH THE LATEST WAVE
WATCH MODEL TABULAR DATA BRINGING LARGER SWELL INTO SAIPAN WATERS
LATER THIS EVENING AND INTO GUAM WATERS AROUND DAWN THU MORNING.
WILL GO AHEAD WITH A HIGH SURF ADVISORY FOR HIGH SURF BEGINNING
IN ALL SURF ZONES BY TOMORROW MORNING.

&&

.EASTERN MICRONESIA...
CONVECTION ASSOCIATED WITH A TROUGH NEAR KOSRAE EXTENDS
NORTHEASTWARD FROM KOSRAE TO BETWEEN KWAJALEIN AND MAJURO. LATEST
IR SAT IMAGERY SHOWS FEW COLD CLOUD TOPS EAST OF KOSRAE WHICH
SUGGESTS THAT THE OCCURRENCE OF SCATTERED SHOWERS WILL LIKELY BE
LIMITED TO THIS EVENING. MODEL CONSENSUS GENERALLY KEEPS SHOWERS
NORTH OF MAJURO AS WELL SO BOTH LOCATIONS ARE EXPECTED TO SEE A
DRIER TRADE-WIND PATTERN THROUGH EARLY NEXT WEEK. THE TROUGH WILL
BRING SCATTERED SHOWERS TO POHNPEI LATER THURSDAY...BUT SHOWERS
WILL QUICKLY BECOME ISOLATED DURING THE NIGHTTIME HOURS.
AFTERWARD...POHNPEI WILL SEE DRIER CONDITIONS SIMILAR TO AREAS
FARTHER EAST. WAVE WATCH GUIDANCE STILL INDICATES HIGHER SEAS
GOING IN TO THE WEEKEND. A LONG FETCH OF STRONG WINDS TO THE
NORTHWEST OF MID LATITUDE LOW PRESSURE CENTERED NORTHEAST OF WAKE
ISLAND WILL SEND LARGER SWELL SOUTHWESTWARD. DISPERSION OF SWELL
ENERGY SHOULD KEEP RISK OF HIGH SURF LOW ACROSS ALL MICRONESIAN
FORECAST POINTS.

&&

.WESTERN MICRONESIA...
SATELLITE IMAGERY SHOWS THAT A TROUGH IS JUST MOVING BY CHUUK. AS
A RESULT...MOST CONVECTION IS NOW PAST THE AREA. THIS WILL ALLOW
DRY TRADES TO SETTLE IN FOR THE WEEKEND. IR SAT IMAGERY SHOWS
THAT CONVECTION ASSOCIATED WITH ANOTHER SURFACE TROUGH NEAR YAP
IS BEGINNING TO PULSE DOWN SO AM EXPECTING SCATTERED SHOWERS TO
END AROUND MIDNIGHT TONIGHT AT YAP. SHOWER COVERAGE SHOULD BE
MINIMAL FOR KOROR AS THE TROUGH PASSES BY THU SO ONLY ISOLATED
COVERAGE IS EXPECTED FOR THE NEXT SEVERAL DAYS. SIMILAR TO
POHNPEI...WAVE WATCH MODEL GUIDANCE INDICATES BUILDING SEAS BY
THU...BUT A HIGH SURF ADVISORY IS NOT EXPECTED SINCE LONG PERIOD
SWELL ENERGY WILL BE DIVIDED BETWEEN NORTH AND EAST COMPONENTS.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...HIGH SURF ADVISORY FROM 6 AM THURSDAY TO 3 PM CHST SUNDAY FOR 
     GUZ001>004.

MARIANAS WATERS...NONE.
&&

$$

MCELROY/W. AYDLETT

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
To unsubscribe from WX-TROPL send e-mail to [email-masked] with
"unsub wx-tropl" in the body of your message. For help with WX-TROPL
write to [email-masked]. For more information on tropical weather products, see the NHC Homepage at http://www.nhc.noaa.gov.