Area Forecast Discussion Issued by NWS Pago Pago
000
FXZS60 NSTU 220111
AFDPPG
AREA FORECAST DISCUSSION FOR AMERICAN SAMOA AND INDEPENDENT SAMOA
NATIONAL WEATHER SERVICE PAGO PAGO AS
211 PM SST TUE MAY 21 2013
.SHORT TERM...
.TONIGHT THROUGH THURSDAY NIGHT...SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS ARE OCCURRING TO THE NORTH OF UPOLU AND WEST OF SAVAII.
THE WATER VAPOR IMAGERY SHOWS DRY SUBSIDENCE AIR TO THE EAST OF
MANUA WHILE A BULK OF HEAVY MOISTURE OVERSHADOWS THE MOVEMENT OF
LOW-LEVEL CLOUDS JUST TO THE NORTH OF THE SAMOAN ISLANDS. A MID-
LEVEL HIGH CENTERED SOUTHEAST OF THE AREA WILL REMAIN NEARLY
STATIONARY THUS KEEPING HEAVY MOISTURE AND CLOUDS FARTHER NORTH
OF THE REGION THROUGH THURSDAY. THE LATEST GFS MODEL SHOWS
SCATTERED SHOWERS AND POSSIBLE TSTMS MOVING OVER SAVAII TONIGHT
INTO WEDNESDAY AFTERNOON. JUST TO THE SOUTH OF THE REGION...A
SURFACE RIDGE WILL REMAIN NEARLY STATIONARY HENCE THE TRADE-WIND
REGIME NEAR THE REGION WILL USHER FAVORABLE DRY WEATHER CONDITIONS
EXCEPT FOR ISOLATED SHOWERS DURING THE NEXT COUPLE OF DAYS.
THEREFORE...ANTICIPATE PARTLY TO MOSTLY CLOUDY SKIES AND ISOLATED
SHOWERS OVER AMERICAN SAMOA AND SCATTERED SHOWERS WEST OF TUTUILA
DURING THE NEXT 24 HOURS.
.LONG TERM...
.FRIDAY THROUGH TUESDAY...A SURFACE RIDGE TO THE SOUTH WILL
MAINTAIN ITS POSITION OVER THE NEXT SEVERAL DAYS. CLOUDS AND
ISOLATED SHOWERS WILL MOVE ACROSS THE REGION DURING THE MEMORIAL
HOLIDAY WEEKEND. A SURFACE TROUGH FROM THE SOUTHWEST OF SAMOA WILL
INFLUENCE THE LOCATION AND MOVEMENT OF THE SURFACE RIDGE AFTER
MONDAY NIGHT YET IT/S STILL TOO EARLY TO COMMENT ON THIS
SITUATION. THE GFS MODEL RESOLUTION SHOWS WIND SPEED DIMINISHING
TO NEAR 5 TO 10 KT ON MONDAY NIGHT...BUT WILL KEEP THE PREVIOUS
FCST THE SAME. FOR NOW...EXPECT PARTLY TO MOSTLY CLOUDY SKIES AND
MODERATE TRADE-WINDS DURING THE LONG-TERM FCST PERIOD.
&&
.MARINE...FRESH TO BREEZY WINDS TONIGHT WILL GENERATE HAZARDOUS
SEA HEIGHTS OF 6 TO 8 FEET TONIGHT. A STRONG AREA OF HIGH PRESSURE
NEAR THE SAMOAN ISLANDS WILL PRODUCE CHOPPY WATERS OVER THE NEXT
COUPLE OF DAYS. THE LATEST WAVE WATCH MODEL SHOWS SEA HEIGHTS TO
REMAIN NEAR 5 TO 7 FEET AFTER TONIGHT. WILL KEEP THE SMALL CRAFT
ADVISORY EFFECTIVE DURING THE REST OF THE WEEK.
&&
.PPG WATCHES/WARNINGS/ADVISORIES...
.A SMALL CRAFT ADVISORY.
&&
$$
BAQUI