Subject: Western Pacific: Synoptic Discussion For The Marianas

From: LDM Weather <[email-masked]>
Date: Wed, 8 Sep 2010 02:09:59 -0500

964 
FXPQ60 PGUM 080709
AFDPQ 

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
509 PM CHST WED SEP 8 2010

.SYNOPSIS...
PGUA WSR-88D SHOWS ISOLATED SHOWERS MOVING THROUGH THE MARIANAS.
AN UPPER-LEVEL LOW EAST-NORTHEAST OF THE MARIANAS IS CRAWLING
TOWARDS THE MARIANAS. VISIBLE SATELLITE SHOWS A STEADY INCREASE OF
DEEP CONVECTION NEAR 150E ASSOCIATED WITH THE UPPER- LEVEL LOW.

&&

.DISCUSSION...
NO MAJOR CHANGES WERE MADE TO THE FORECAST AS MODELS SUGGESTED
LITTLE CHANGE. THE SLIGHT CHANCE OF THUNDERSTORMS FOR TONIGHT WAS
EXTENDED INTO THURSDAY AS THE UPPER-LEVEL LOW SLOWLY APPROACHES
THE MARIANAS. ECMWF PROVIDES A GOOD SOAKING...BUT STUCK WITH THE
MORE CONSERVATIVE GFS. IF THE UPPER LOW CONTINUES ITS SLOW
MOVEMENT INTO THE AREA...THUNDERSTORMS COULD BE EXTENDED INTO
THURSDAY NIGHT. OTHERWISE...MODELS INDICATE DRIER CONDITIONS
THROUGH THE WEEKEND.

&&

.EASTERN MICRONESIA...
SATELLITE IMAGERY SHOWS THE ITCZ ACTIVE BETWEEN 5N AND 10N AND 
AFFECTING ALL MONITORED ISLANDS FROM CHUUK EASTWARD. SMALL 
FLUCTUATIONS HAVE EACH ISLAND GROUP MOVING IN AND OUT OF SCATTERED 
SHOWERS WITH NO REAL CONSISTENCY FROM ONE MODEL TO THE NEXT. BEST TO
KEEP THE FOUR ISLANDS MOSTLY CLOUDY THROUGH OUT THE FORECAST PERIOD 
WITH SOME HIT AND MISS FOR SCATTERED SHOWERS. ONE EXCEPTION IS FOR 
KOSRAE WHICH IS ALONG THE SOUTHERN EDGE OF THE CONVERGENCE ZONE AND 
THE MODELS ARE RELATIVELY CONSISTENT WITH PUSHING THE ITCZ FURTHER 
NORTH BY THE WEEKEND FOR THIS AREA. 

.MARINE...A HIGH SURF ADVISORY REMAINS IN EFFECT FOR KOSRAE ALONG 
EAST- AND SOUTH-FACING SHORES. WAVEWATCH MODEL REMAINS CONSISTENT AND 
SHOWS COMBINED SEA HEIGHTS PEAKING LATE TONIGHT OR EARLY THURSDAY 
WITH SURF FALLING BELOW THE 8FT CRITERION LEVELS BY FRIDAY.

&&

.WESTERN MICRONESIA...
AS DISCUSSED ABOVE...WEATHER FOR CHUUK IS SIMILAR TO THAT FOR 
POHNPEI AND MAJURO WITH MOSTLY CLOUDY AND IN AND OUT SCATTERED 
SHOWER CONDITIONS. SATELLITE IMAGERY SHOWS THAT A WEAK WAVE APPEARS  
READY TO MOVE INTO THE CHUUK FROM THE SOUTH TONIGHT. MODEL 
GUIDANCE FOR YAP AND PALAU REMAINS THE SAME WITH LITTLE SIGNIFICANT 
FEATURE AFFECTING THE REGION DURING THE FORECAST PERIOD. THE TUTT 
CELL CURRENTLY OVER THE MARIANAS MAY HELP DRAW THE CONVECTION IN THE 
ITCZ FURTHER NORTH BY FRIDAY OR SATURDAY BUT THE MODELS ARE NOT 
CONSISTENT...ESPECIALLY WITH THESE UPPER-AIR FEATURES. RIGHT 
NOW...SURFACE WINDS ARE ALL FROM THE EAST DOWN TO THE EQUATOR WITH 
NO MONSOON IN SIGHT...A RELATIVELY DRY PATTERN

&&

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

$$

M. AYDLETT/EDSON

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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.