FXHW60 PHFO 092020 AAA
AFDHFO
AREA FORECAST DISCUSSION CORRECTED
NATIONAL WEATHER SERVICE HONOLULU HI
1015 AM HST WED DEC 9 2009
CORRECTION FOR MARINE AND WATCH SECTION.
.SYNOPSIS...
A HIGH PRESSURE RIDGE OVER THE ISLANDS AND A DRY AIR MASS WILL
PRODUCE MOSTLY SUNNY DAYS AND CLEAR NIGHTS. PRESENTLY WINDS ARE
LIGHT. GENTLE TO MODERATE TRADE WINDS WILL RETURN FRIDAY BUT THEN
BECOME LIGHT AGAIN THIS WEEKEND.
&&
.DISCUSSION...
THE ISLANDS ARE NEARLY CLOUD FREE ALTHOUGH SATELLITE IMAGERY SHOWS
SMALL WEAK MOSTLY SPARSE CLOUDS OVER ADJACENT OCEAN AREAS. THE
TEMPERATURE INVERSION IS A VERY LOW 3000 TO 4500 FEET AND
PRECIPITABLE WATER STILL NEAR 1 INCH. EXPECT NEGLIGIBLE TO
NON-EXISTENT SHOWER ACTIVITY DESPITE SOME AFTERNOON CLOUD
FORMATION FROM SEA BREEZES AND AFTERNOON HEATING OF THE LAND.
NIGHTTIME CLEAR SKIES AND COOL OVERNIGHT TEMPERATURES SHOULD BE THE
RULE. DEWPOINT TEMPERATURES ARE IN THE UPPER 50S TO 60S...OVERNIGHT
TEMPERATURES SHOULD ALSO BE IN THIS RANGE. LITTLE CHANGE IN THE
WEATHER PATTERN EXPECTED...THE ISLANDS SHOULD REMAIN MOSTLY DRY
THROUGH THE WEEKEND.
TRADES WILL BE LIGHT WITH AFTERNOON SEA BREEZES EXPECTED TODAY
AND PROBABLY THURSDAY TOO SINCE THE SURFACE RIDGE IS SO CLOSE TO
THE ISLANDS. FIRMER TRADE WINDS WILL RETURN FOR ONLY FRIDAY WHEN A
SURFACE HIGH PASSES BY TO THE NORTH...BUT THEN THE SURFACE RIDGE
WILL SHIFT BACK OVER THE ISLANDS THIS WEEKEND PRODUCING GENTLE
SOUTHEASTERLY OR VARIABLE WINDS.
GFS AND NOGAPS HAVE DELAYED THE APPROACH OF A COLD FRONT UNTIL
WEDNESDAY. THE GFS SUGGESTS THE POSSIBILITY IT MAY BE DISSIPATING
IF IT DOES REACH KAUAI. THE NEW EUROPEAN MODEL DIFFERS IN THE
MOVEMENT OF THE ASSOCIATED PARENT AND SUGGESTS A STRONGER UPPER
TROUGH THAT PUSHES THE FRONT SLOWLY THROUGH OUR ISLANDS LATE MONDAY
INTO EARLY WEDNESDAY. THEREFORE CONFIDENCE IN THIS FEATURE STILL LOW
AND POSSIBILITY OF ONLY A DISSIPATING FRONT IF IT DOES REACH THE
MAIN HAWAIIAN ISLANDS.
&&
.MARINE...
THE NORTHWEST SWELL DECREASED OVER THE PAST NIGHT BUT HAS BEEN MORE
STEADY THIS MORNING NEAR 13 FEET AT BUOY 51001 LOCATED NORTHWEST OF
KAUAI...AND NEARLY 11 FEET AT WAIMEA BAY...BOTH BUOYS PERIOD AT 15
SECONDS. THIS IS HIGH ENOUGH FOR A LOW END WARNING ON NORTH AND
WEST SHORES ON SOME ISLANDS EXPOSED TO THE SWELL. MORE LOWERING OF
THE SWELL IS EXPECTED THEREFORE HIGH SURF WARNINGS MAY BE DROPPED
THIS AFTERNOON IN FAVOR OF ADVISORIES FOR TONIGHT AND THURSDAY. HIGH
SURF ADVISORIES WILL LIKELY BE UP FOR THIS WEEKEND.
THE SMALL CRAFT ADVISORIES CONTINUE BECAUSE OF THE NORTHWEST SWELL
TODAY...BUT SWELLS MAY BE ADJUSTED DOWNWARD FOR THURSDAY IN WHICH
CASE SOME OR ALL AREAS WOULD SEE THE END OF SMALL CRAFT ADVISORIES
BEFORE THURSDAY.
&&
.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF WARNING UNTIL 6 PM HST TODAY FOR NORTH AND WEST FACING
SHORES OF NIIHAU KAUAI OAHU MOLOKAI AND MAUI.
HIGH SURF ADVISORY UNTIL 6 PM HST TODAY FOR EAST FACING SHORES
OF OAHU...AND WEST AND NORTHEAST FACING SHORES OF THE BIG ISLAND
EXPOSED TO THE NORTHWEST SWELL.
SMALL CRAFT ADVISORY UNTIL 6 PM HST THURSDAY FOR ALL WATERS EXCEPT
THE PAILOLO CHANNEL AND MAALAEA BAY FOR THE LARGE NORTHWEST SWELL.
&&
$$
HOAG
