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278
FXZS60 NSTU 150115
AFDPPG
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PAGO PAGO AS
215 PM SST SUN JUL 15 2018
.SHORT TERM...
.TONIGHT THROUGH TUESDAY NIGHT...GFS SWEEPS SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS NEAR AND ABOVE SAVAII AND UPOLU ON MONDAY
AND
MONDAY NIGHT AS A RESULT OF A DEVELOPING SURFACE TROUGH FROM THE WEST.
AHEAD OF THIS TROUGH LIES A SURFACE RIDGE THAT WILL MOVE CLOSER TO THE
SOUTH OF TUTUILA AND MANU`A, AND IT`S UNCLEAR WHETHER THE EXPECTED
TROUGH WILL
DETERIORATE OR CONTINUE TO MOVE PAST AMERICAN SAMOA THROUGH EARLY
TUESDAY MORNING.
HENCE, GENTLE TO MODERATE EASTERLIES WILL PREVAIL AS THE BROAD AREA
OF HIGH PRESSURE DRIFTS EAST SLOWLY AND AWAY FROM THE REGION THROUGH
TUESDAY.
THUS, ANTICIPATE ISOLATED TO SCATTERED MID-MORNING TO AFTERNOON
SHOWERS EAST OF UPOLU,
BUT SCATTERED TO NUMEROUS SHOWERS AND POSSIBLE MID-MORNING TO
AFTERNOON THUNDERSTORMS
OVER UPOLU AND SAVAII THROUGH SHORT TERM.
.LONG TERM...
.WEDNESDAY THROUGH SUNDAY...GFS INTRODUCES A SURFACE TROUGH TO
MIGRATE EAST OF
UPOLU AND TUTUILA ON THURSDAY NIGHT INTO FRIDAY MORNING. THIS
EXPECTED SITUATION
COULD BRING HEAVY MOISTURE AND SCATTERED TO NUMEROUS SHOWERS ACROSS
THE MAIN SAMOAN ISLAND
CHAIN. ASIDE FROM THIS, SEA BREEZE EFFECTS WILL DAMPEN THE FORECAST
ZONES WITH AT LEAST
MID-MORNING TO AFTERNOON ISOLATED TO SCATTERED SHOWERS. AS A RESULT,
WILL MONITOR THE EXPECTED
TROUGH THEN PROVIDE UPDATES WHEN NECESSARY...AND WILL KEEP THE
SHOWER COVERAGE TO A
MINIMAL AS SUGGESTED FROM PREVIOUS FORECAST PACKAGE.
&&
.MARINE...FNMOC WAVE WATCH III BRINGS COMBINED SEA HEIGHTS TO NEAR 5
TO 7 FT ON MONDAY,
YET CLEARLY A LONG PERIOD SOUTH SWELL WILL CONTINUE THROUGH TONIGHT
THEN DISSIPATE
AT LEAST BEFORE NOON ON MONDAY. ANOTHER LONG PERIOD SOUTHWEST SWELL
WILL MOVE ACROSS THE
SAMOAN WATERS THROUGH WEDNESDAY NIGHT, AND THIS WILL EITHER BOOST
SURF HEIGHTS TO ABOVE
ADVISORY THRESHOLDS OR NEAR BORDERLINE ADVISORY. FOR NOW, WILL KEEP
AN EYE ON THIS EXPECTED
SITUATION. ANTICIPATE SEAS AND SURFS TO REMAIN NEAR MODERATE LEVELS
OF 6 TO 7 FEET AFTER TONIGHT.
&&
.PPG WATCHES/WARNINGS/ADVISORIES...
.SMALL CRAFT ADVISORY.
&&
$$
CB