FXHW60 PHFO 011956
AFDHFO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
950 AM HST TUE DEC 1 2009
.SYNOPSIS...
A WEAK RIDGE NORTH OF THE STATE TODAY WILL BRING MOSTLY LIGHT TRADES
TO THE ISLANDS. THE RIDGE WILL DRIFT SOUTH OVER THE STATE TONIGHT
THROUGH LATE WEDNESDAY RESULTING IN LIGHT AND VARIABLE WINDS. AN
APPROACHING FRONT WILL BRING SOUTHWEST WINDS ON THURSDAY...WITH THE
FRONT BRINGING CLOUDS AND SHOWERS AS IT MOVES DOWN THE ISLAND CHAIN
THURSDAY NIGHT AND FRIDAY. THE FRONT WILL STALL AND WEAKEN NEAR THE
BIG ISLAND ON SATURDAY...WITH ANOTHER FRONT APPROACHING EARLY NEXT
WEEK.
&&
.DISCUSSION...
A QUIET WEATHER PATTERN IS OVER THE STATE THIS MORNING WITH LIGHT
TRADES AT THE SURFACE AND A DRY SUBSIDENT AIRMASS ALOFT. AN UPPER
TROUGH IS WELL SOUTHEAST OF THE BIG ISLAND AND SLOWLY MOVING
EAST...AWAY FROM THE AREA...BUT SOME LOW LEVEL MOISTURE IS BEING
CAUGHT IN THE TRADES AND WRAPPING BACK TOWARDS THE SOUTHEAST BIG
ISLAND COAST. INCREASING SHOWERS ARE BEING DETECTED BY THE SOUTH
POINT 88-D OVER THE COASTAL WATERS. OVER THE SMALLER ISLANDS...ONLY
ISOLATED LIGHT SHOWERS ARE SEEN OVER WINDWARD AND MOUNTAIN LOCATIONS.
THE FORECAST MODELS AGREE IN THE PATTERN EVOLUTION THROUGH THE REST
OF THE WEEK. THE SURFACE RIDGE NORTH OF THE ISLANDS IS SET TO DRIFT
SOUTHWARD ACROSS THE STATE TONIGHT THROUGH LATE WEDNESDAY...BRINGING
LIGHT AND VARIABLE WINDS TO THE AREA. THE AIRMASS REMAINS DRY
THROUGH THIS TIME PERIOD FOR MOST OF THE AREA...THE MOST MOISTURE
REMAINS OVER WINDWARD BIG ISLAND...BUT EVEN THERE SHOWERS WILL BE
SPARSE. LIGHT WINDS AND DRY AIR WILL RESULT IN COOLER NIGHTTIME
TEMPERATURES TONIGHT AND WEDNESDAY NIGHT.
THE SURFACE RIDGE AXIS MOVES SOUTHEAST OF THE AREA THURSDAY AS A
DEVELOPING TROUGH AND COLD FRONT APPROACHES FROM THE NORTHWEST. THIS
WILL BRING MODERATE SOUTHWESTERLY WINDS BY THURSDAY AFTERNOON. THE
COLD FRONT MOVES ACROSS KAUAI THURSDAY NIGHT...OAHU EARLY
FRIDAY...AND MAUI COUNTY FRIDAY AFTERNOON BRINGING INCREASING
SHOWERS AND A NORTHERLY WIND SHIFT. THE FRONT BEGINS TO LOSE UPPER
LEVEL SUPPORT FRIDAY NIGHT AND SATURDAY AS THE UPPER TROUGH LIFTS
NORTHEAST...AND IT STALLS AND WEAKENS NEAR THE BIG ISLAND DURING
THIS TIME PERIOD.
THE PATTERN SEEMS TO REMAIN PROGRESSIVE OVER THE WEEKEND WITH SHORT
WAVE RIDGING PASSING BY EARLY SUNDAY FOLLOWED BY A WEAK COLD FRONT
ON MONDAY. CONDITIONS WILL BE UNSETTLED...HOWEVER IT REMAIN UNCLEAR
THAT THE MONDAY COLD FRONT WILL HAVE ENOUGH SUPPORT TO BRING MUCH
RAIN OR WIND TO THE ISLANDS.
&&
.MARINE...
ADDITIONAL INCOMING NW SWELL MEANS THAT BOTH THESE FLAGS WILL NEED
TO BE HOISTED AGAIN SOON...WITH THE FIRST OF SEVERAL SOLID NW
SWELLS BUILDING ON WEDNESDAY. THIS SWELL WILL RESULT IN SURF ABOVE
ADVISORY LEVELS ALONG N AND W FACING SHORES OF MOST ISLANDS...AND
COMBINED SEAS ABOVE 10 FEET IN MOST MARINE ZONES.
&&
.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
BRENCHLEY
