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000
FXHW60 PHFO 030639
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
840 PM HST TUE SEP 2 2014

.SYNOPSIS...
LIGHT TO MODERATE TRADE WINDS WILL CONTINUE FOR MUCH OF THE UPCOMING
WEEK...AND LIKELY INTO THE WEEKEND. THE TRADE WINDS WILL FOCUS
CLOUDS AND SHOWERS OVER WINDWARD SLOPES AND COASTS...MAINLY DURING
NIGHTS AND MORNINGS. HOWEVER...THE WINDS WILL BE LIGHT ENOUGH TO
ALLOW AFTERNOON SEA BREEZES TO DRIVE CLOUD AND SHOWER FORMATION OVER
LEEWARD SLOPES AND COASTS EACH AFTERNOON...BEFORE SKIES GRADUALLY
CLEAR EACH EVENING.

&&

.DISCUSSION...
WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL HIGH AND VERY DRY
CONDITIONS ALOFT OVER THE ISLANDS...WHILE AMPLE LOW LEVEL MOISTURE
IS CAPPED BELOW AN INVERSION THAT EXTENDS AS HIGH AS 10 THOUSAND
FEET...BASED ON AFTERNOON SOUNDINGS...AND THE FACT THAT LOW CLOUD
TOPS DID NOT EXTEND HIGHER THAN THE BIG ISLAND SUMMITS THIS
AFTERNOON. AT THE SURFACE...MODERATE HIGH PRESSURE IS LOCATED FAR TO
THE NNE...WITH AN ASSOCIATED RIDGE PASSING SEVERAL HUNDRED MILES TO
THE N. LOW PRESSURE...FORMER TC MARIE...IS FAR NE OF THE STATE AND
DRIFTING W. MIMIC TOTAL PRECIPITABLE WATER IMAGERY SHOWS AN AREA OF
HIGHER MOISTURE EXTENDING UP TO 200 MILES E OF THE ISLANDS...WITH
DRIER AIR FARTHER UPSTREAM.

THE PRESSURE GRADIENT ACROSS THE ISLANDS REMAINS ON THE LIGHT SIDE
DUE TO OUR SEPARATION FROM THE HIGH AND THE PRESENCE OF FORMER
MARIE...AND THIS GENERAL PATTERN WILL REMAIN IN PLACE FOR THE NEXT
SEVERAL DAYS...POSSIBLY THROUGH THE WEEKEND. THUS LIGHT TO MODERATE
TRADE WINDS ARE EXPECTED TO DELIVER CLOUDS AND A FEW SHOWERS TO
WINDWARD AREAS...MAINLY DURING NIGHTS AND MORNINGS. THE FOCUS FOR
CLOUDS AND SHOWERS WILL SHIFT TO LEEWARD SLOPES AND COASTS IN THE
AFTERNOON AND EARLY EVENING...AFTER WHICH GENERAL CLEARING CAN BE
EXPECTED OVERNIGHT.

AN AREA OF LOW CLOUDS IS CURRENTLY LOCATED NE OF MAUI AND THE BIG
ISLAND...MOVING W NEAR 10 MPH. THESE CLOUDS ARE AN INDICATOR OF THE
HIGHER MOISTURE JUST UPSTREAM OF THE STATE...AND WILL HELP TO
ENHANCE TRADE WIND SHOWERS MAINLY ACROSS WINDWARD SECTIONS TONIGHT
INTO WEDNESDAY. GFS FORECAST SOUNDINGS/ MOISTURE PLOTS SHOW DRIER
AND MORE STABLE CONDITIONS SPREADING ACROSS THE ISLANDS LATER
WEDNESDAY...WITH LOWER RAINFALL CHANCES EXPECTED.

BY THE END OF THE WEEK...BOTH GFS AND ECMWF CONTINUE TO SHOW A
TONGUE OF MOISTURE TRAILING FROM FORMER MARIE REACHING THE ISLANDS
FRIDAY AND LINGERING INTO SATURDAY. FORECAST SOUNDINGS SHOW
INCREASING MOISTURE DEPTH BACK TO NEAR 10KFT. WHILE EARLIER MODEL
RUNS SHOWED POTENTIAL FOR INCREASING TRADE WINDS THIS WEEKEND...
LATEST GUIDANCE IS TRENDING TOWARD A CONTINUATION OF LIGHTER WINDS
AS WE HEAD INTO NEXT WEEK...AS THE RIDGE ASSOCIATED WITH THE HIGH IS
SHUNTED SOUTHWARD BY A LARGE LOW DEVELOPING TO THE NW OF THE STATE.

&&

.AVIATION...
LIGHT TO MODERATE TRADES WILL CONTINUE OVER THE NEXT FEW DAYS. WINDS
SHOULD REMAIN LIGHT ENOUGH TO LIMIT THE NEED FOR A LOW LEVEL TURB
AIRMET. SHOWERS WILL FAVOR WINDWARD AND MAUKA AREAS OVERNIGHT AND IN
THE EARLY MORNING AS SKIES GRADUALLY CLEAR LEEWARD. AFTERNOON AND
EVENING CLOUDS AND SHOWERS ARE EXPECTED OVER LEEWARD SLOPES AND
COASTS AGAIN ON WEDNESDAY. MVFR CONDITIONS ARE LIKELY WITHIN THESE
SHOWERS. OTHERWISE...VFR WILL PREVAIL.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
FORERUNNERS OF A VERY LONG PERIOD S SWELL /20-25 SECONDS/ THAT
ARRIVED EARLY TODAY ARE EXPECTED TO BUILD FURTHER TONIGHT...ALTHOUGH
AT LOW HEIGHTS. THE LARGEST PART OF THE SWELL WILL MISS US TO THE
E...AS SEEN BY THE GREATER LONG-PERIOD ENERGY AT BUOY 51004 SE OF
THE ISLANDS AS OPPOSED TO THE MUCH LOWER ENERGY READINGS AT BUOY
51003 TO THE SE. WITH THE BULK OF THE SWELL ENERGY PASSING E OF THE
ISLANDS...THE CURRENT EXPECTATION IS THAT SURF WILL REMAIN JUST
BELOW ADVISORY LEVELS ALONG S FACING SHORES. WILL MONITOR BUOY
OBSERVATIONS FOR POTENTIAL LARGER THAN EXPECTED SWELLS.

FORECAST MODELS SHOW A LARGE LOW DEVELOPING WELL NW OF THE ISLANDS
THIS WEEK...WITH LATEST FORECASTS FROM THE OCEAN PREDICTION CENTER
ANTICIPATING STORM FORCE WINDS. THIS LOW WILL GENERATE A NW SWELL
THAT IS EXPECTED TO ARRIVE MONDAY AND PEAK ON TUESDAY. IT IS TOO
EARLY FOR SPECIFICS AS THE LOW HAS YET TO DEVELOP...BUT RESULTANT
SURF LOOKS TO REMAIN BELOW ADVISORY LEVEL HEIGHTS ALONG N AND W
FACING SHORES.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

BIRCHARD






000
FXHW60 PHFO 030639
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
840 PM HST TUE SEP 2 2014

.SYNOPSIS...
LIGHT TO MODERATE TRADE WINDS WILL CONTINUE FOR MUCH OF THE UPCOMING
WEEK...AND LIKELY INTO THE WEEKEND. THE TRADE WINDS WILL FOCUS
CLOUDS AND SHOWERS OVER WINDWARD SLOPES AND COASTS...MAINLY DURING
NIGHTS AND MORNINGS. HOWEVER...THE WINDS WILL BE LIGHT ENOUGH TO
ALLOW AFTERNOON SEA BREEZES TO DRIVE CLOUD AND SHOWER FORMATION OVER
LEEWARD SLOPES AND COASTS EACH AFTERNOON...BEFORE SKIES GRADUALLY
CLEAR EACH EVENING.

&&

.DISCUSSION...
WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL HIGH AND VERY DRY
CONDITIONS ALOFT OVER THE ISLANDS...WHILE AMPLE LOW LEVEL MOISTURE
IS CAPPED BELOW AN INVERSION THAT EXTENDS AS HIGH AS 10 THOUSAND
FEET...BASED ON AFTERNOON SOUNDINGS...AND THE FACT THAT LOW CLOUD
TOPS DID NOT EXTEND HIGHER THAN THE BIG ISLAND SUMMITS THIS
AFTERNOON. AT THE SURFACE...MODERATE HIGH PRESSURE IS LOCATED FAR TO
THE NNE...WITH AN ASSOCIATED RIDGE PASSING SEVERAL HUNDRED MILES TO
THE N. LOW PRESSURE...FORMER TC MARIE...IS FAR NE OF THE STATE AND
DRIFTING W. MIMIC TOTAL PRECIPITABLE WATER IMAGERY SHOWS AN AREA OF
HIGHER MOISTURE EXTENDING UP TO 200 MILES E OF THE ISLANDS...WITH
DRIER AIR FARTHER UPSTREAM.

THE PRESSURE GRADIENT ACROSS THE ISLANDS REMAINS ON THE LIGHT SIDE
DUE TO OUR SEPARATION FROM THE HIGH AND THE PRESENCE OF FORMER
MARIE...AND THIS GENERAL PATTERN WILL REMAIN IN PLACE FOR THE NEXT
SEVERAL DAYS...POSSIBLY THROUGH THE WEEKEND. THUS LIGHT TO MODERATE
TRADE WINDS ARE EXPECTED TO DELIVER CLOUDS AND A FEW SHOWERS TO
WINDWARD AREAS...MAINLY DURING NIGHTS AND MORNINGS. THE FOCUS FOR
CLOUDS AND SHOWERS WILL SHIFT TO LEEWARD SLOPES AND COASTS IN THE
AFTERNOON AND EARLY EVENING...AFTER WHICH GENERAL CLEARING CAN BE
EXPECTED OVERNIGHT.

AN AREA OF LOW CLOUDS IS CURRENTLY LOCATED NE OF MAUI AND THE BIG
ISLAND...MOVING W NEAR 10 MPH. THESE CLOUDS ARE AN INDICATOR OF THE
HIGHER MOISTURE JUST UPSTREAM OF THE STATE...AND WILL HELP TO
ENHANCE TRADE WIND SHOWERS MAINLY ACROSS WINDWARD SECTIONS TONIGHT
INTO WEDNESDAY. GFS FORECAST SOUNDINGS/ MOISTURE PLOTS SHOW DRIER
AND MORE STABLE CONDITIONS SPREADING ACROSS THE ISLANDS LATER
WEDNESDAY...WITH LOWER RAINFALL CHANCES EXPECTED.

BY THE END OF THE WEEK...BOTH GFS AND ECMWF CONTINUE TO SHOW A
TONGUE OF MOISTURE TRAILING FROM FORMER MARIE REACHING THE ISLANDS
FRIDAY AND LINGERING INTO SATURDAY. FORECAST SOUNDINGS SHOW
INCREASING MOISTURE DEPTH BACK TO NEAR 10KFT. WHILE EARLIER MODEL
RUNS SHOWED POTENTIAL FOR INCREASING TRADE WINDS THIS WEEKEND...
LATEST GUIDANCE IS TRENDING TOWARD A CONTINUATION OF LIGHTER WINDS
AS WE HEAD INTO NEXT WEEK...AS THE RIDGE ASSOCIATED WITH THE HIGH IS
SHUNTED SOUTHWARD BY A LARGE LOW DEVELOPING TO THE NW OF THE STATE.

&&

.AVIATION...
LIGHT TO MODERATE TRADES WILL CONTINUE OVER THE NEXT FEW DAYS. WINDS
SHOULD REMAIN LIGHT ENOUGH TO LIMIT THE NEED FOR A LOW LEVEL TURB
AIRMET. SHOWERS WILL FAVOR WINDWARD AND MAUKA AREAS OVERNIGHT AND IN
THE EARLY MORNING AS SKIES GRADUALLY CLEAR LEEWARD. AFTERNOON AND
EVENING CLOUDS AND SHOWERS ARE EXPECTED OVER LEEWARD SLOPES AND
COASTS AGAIN ON WEDNESDAY. MVFR CONDITIONS ARE LIKELY WITHIN THESE
SHOWERS. OTHERWISE...VFR WILL PREVAIL.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
FORERUNNERS OF A VERY LONG PERIOD S SWELL /20-25 SECONDS/ THAT
ARRIVED EARLY TODAY ARE EXPECTED TO BUILD FURTHER TONIGHT...ALTHOUGH
AT LOW HEIGHTS. THE LARGEST PART OF THE SWELL WILL MISS US TO THE
E...AS SEEN BY THE GREATER LONG-PERIOD ENERGY AT BUOY 51004 SE OF
THE ISLANDS AS OPPOSED TO THE MUCH LOWER ENERGY READINGS AT BUOY
51003 TO THE SE. WITH THE BULK OF THE SWELL ENERGY PASSING E OF THE
ISLANDS...THE CURRENT EXPECTATION IS THAT SURF WILL REMAIN JUST
BELOW ADVISORY LEVELS ALONG S FACING SHORES. WILL MONITOR BUOY
OBSERVATIONS FOR POTENTIAL LARGER THAN EXPECTED SWELLS.

FORECAST MODELS SHOW A LARGE LOW DEVELOPING WELL NW OF THE ISLANDS
THIS WEEK...WITH LATEST FORECASTS FROM THE OCEAN PREDICTION CENTER
ANTICIPATING STORM FORCE WINDS. THIS LOW WILL GENERATE A NW SWELL
THAT IS EXPECTED TO ARRIVE MONDAY AND PEAK ON TUESDAY. IT IS TOO
EARLY FOR SPECIFICS AS THE LOW HAS YET TO DEVELOP...BUT RESULTANT
SURF LOOKS TO REMAIN BELOW ADVISORY LEVEL HEIGHTS ALONG N AND W
FACING SHORES.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

BIRCHARD







000
FXHW60 PHFO 030152
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST TUE SEP 2 2014

.SYNOPSIS...
LIGHT TO MODERATE TRADE WINDS WILL CONTINUE FOR MUCH OF THE UPCOMING
WEEK. THE TRADES WILL FOCUS SHOWERS MAINLY ACROSS WINDWARD AREAS...
ESPECIALLY DURING NIGHTS AND MORNINGS...WITH SOME AFTERNOON SHOWERS
ACROSS LEEWARD SECTIONS AS WELL.

&&

.DISCUSSION...
WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL HIGH OVER/JUST SOUTH OF THE
STATE...WITH A SHORTWAVE TROUGH FAR TO THE NORTHWEST. AT THE
SURFACE...HIGH PRESSURE IS LOCATED FAR NORTH-NORTHEAST OF THE
STATE...WITH A RIDGE PASSING SEVERAL HUNDRED MILES TO OUR NORTH. LOW
PRESSURE...FORMER TC MARIE...IS FAR NORTHEAST OF THE STATE AND
MOVING GENERALLY WESTWARD. THE 00Z SOUNDING FROM LIHUE SHOWS A
SLIGHTLY LOWER AND STRONGER INVERSION NEAR 6KFT...WITH A
PRECIPITABLE WATER NEAR 1.4 INCHES. EARLY AFTERNOON MIMIC TOTAL
PRECIPITABLE WATER IMAGERY SHOWS AN AREA OF HIGHER MOISTURE
EXTENDING UP TO 200 MILES NORTHEAST AND EAST OF THE STATE...WITH
DRIER AIR FARTHER UPSTREAM.

THE PRESSURE GRADIENT ACROSS THE ISLANDS REMAINS ON THE LIGHT SIDE
DUE TO OUR SEPARATION FROM THE HIGH AND INFLUENCE FROM FORMER MARIE.
HOWEVER...TRADES HAVE BEEN STRONGER AND MORE WIDESPREAD TODAY
COMPARED TO YESTERDAY. THE GRADIENT BETWEEN BUOYS 51100 NORTHEAST OF
THE STATE AND 51004 SOUTHEAST OF THE STATE HAS RISEN BY UP TO A
MILLIBAR OVER THE PAST 24 HOURS. THE ASCAT IMAGERY FROM THIS MORNING
SHOWED WINDS HAVE INCREASED FURTHER SINCE LAST NIGHT...WITH 10-15
KNOTS OF WIND OVER THE WESTERN HALF OF THE STATE AND 15-20 KNOTS
OVER THE EASTERN HALF. THE HIGH RESOLUTION WRF FROM LAST NIGHT...AS
WELL AS THE 12Z/18Z GLOBAL MODELS...SHOW THE STRONGER WINDS
SPREADING WESTWARD ACROSS THE STATE THROUGH TONIGHT AS WELL.

AN AREA OF LOW CLOUDS IS CURRENTLY LOCATED NORTHEAST OF MAUI AND THE
BIG ISLAND...AND IS MOVING WESTWARD AT ABOUT 10 MPH. THESE CLOUDS
ARE AN INDICATOR OF THE HIGHER MOISTURE JUST UPSTREAM OF THE
STATE...AND WILL HELP TO ENHANCE TRADE WIND SHOWERS MAINLY ACROSS
WINDWARD SECTIONS TONIGHT INTO WEDNESDAY. WE HAVE RECEIVED A COUPLE
RAIN GAGE REPORTS OF RATES OVER 1 INCH PER HOUR ON THE BIG ISLAND
FROM SHOWERS THAT LOOK RELATIVELY INNOCUOUS. AS THIS AREA OF
MOISTURE MOVES THROUGH THE STATE TONIGHT...WE WILL REMAIN ON THE
LOOKOUT FOR POTENTIAL FOR LOCALIZED HEAVY RAIN IF SHOWERS BECOME
ANCHORED.

GFS FORECAST SOUNDINGS/MOISTURE PLOTS SHOW DRIER AND MORE STABLE
CONDITIONS SPREADING ACROSS THE ISLANDS DURING THE DAY ON
WEDNESDAY...WITH LOWER RAINFALL CHANCES. THERE SHOULD REMAIN ENOUGH
OF A STRONGER GRADIENT FOR TRADE WINDS TO DOMINATE...WITH LOCALIZED
SEA BREEZES CONFINED TO SHELTERED LEEWARD AREAS. EVEN WITH MORE
PERSISTENT TRADES...WE WILL LIKELY SEE INCREASED CLOUD BUILDUPS
ACROSS INTERIOR AND LEEWARD SECTIONS DURING THE AFTERNOON AND EARLY
EVENING.

BY THE END OF THE WEEK...BOTH GFS AND ECMWF CONTINUE TO SHOW A
TONGUE OF MOISTURE TRAILING FROM FORMER MARIE REACHING THE ISLANDS.
THE GFS IS FASTER/MORE AGGRESSIVE THAN THE ECMWF...BUT BOTH SHOW THE
AREA OF CLOUDS/MOISTURE CURRENTLY EXTENDING DOWN TO 25N BETWEEN
140W/150W REACHING THE ISLANDS LATE THURSDAY/FRIDAY. FORECAST
SOUNDINGS/CROSS SECTIONS SHOW INCREASING MOISTURE DEPTH BACK TO NEAR
10KFT. DURING THIS TIMEFRAME...WINDS MAY ALSO WEAKEN A BIT. THE
REMNANT OF MARIE WILL MOVE WESTWARD AND WEAKEN AS IT ENCROACHES UPON
THE RIDGE. THE GRADIENT ACROSS THE ISLANDS MAY WEAKEN
THURSDAY/FRIDAY...BEFORE STRENGTHENING FURTHER SATURDAY INTO SUNDAY
AS THE LOW DISSIPATES AND WE FEEL MORE OF A DIRECT IMPACT FROM THE
SURFACE HIGH.

&&

.AVIATION...
LIGHT TO MODERATE TRADES WILL CONTINUE OVER THE NEXT FEW DAYS. WINDS
SHOULD REMAIN LIGHT ENOUGH TO LIMIT THE NEED FOR A LOW LEVEL TURB
AIRMET. SHOWERS WILL FAVOR WINDWARD AND MAUKA AREAS...ESPECIALLY
OVERNIGHT AND EARLY MORNING. MVFR CONDITIONS ARE LIKELY WITHIN THESE
SHOWERS. OTHERWISE...VFR WILL PREVAIL.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
FORERUNNERS OF A VERY LONG PERIOD S SWELL /20-25 SECONDS/ THAT
ARRIVED EARLY TODAY ARE EXPECTED TO BUILD FURTHER TONIGHT...ALTHOUGH
AT LOW HEIGHTS. THE LARGEST PART OF THE SWELL WILL MISS US TO THE
EAST...AS SEEN BY THE GREATER LONG-PERIOD ENERGY THAT CONTINUES TO
INCREASE AT BUOY 51004 SOUTHEAST OF THE STATE VERSUS THE MUCH LOWER
ENERGY AT BUOY 51003 SOUTH OF THE STATE. LOCALLY...THE LATEST
OBSERVATIONS FROM THE CDIP BUOY AT BARBERS POINT SHOW INITIAL ENERGY
FROM THIS SWELL IS DOMINATED BY THE FADING SHORTER PERIOD SOUTH
SWELL. AS THIS NEW SWELL FILLS IN...IT WILL PRODUCE SURF NEAR
ADVISORY LEVELS ALONG S FACING SHORES FROM WEDNESDAY INTO THURSDAY.
WITH THE BULK OF THE ENERGY PASSING TO THE EAST...THE CURRENT
EXPECTATION IS THAT SURF WILL REMAIN JUST BELOW ADVISORY LEVELS FOR
SOUTH FACING SHORES. THEREFORE WE WILL HOLD OFF ON AN ADVISORY FOR
NOW...BUT WILL KEEP AN EYE ON CONDITIONS AS THEY BUILD THROUGH THE
NIGHT.

FORECAST MODELS SHOW A FAIRLY LARGE GALE LOW DEVELOPING NW OF THE
STATE THIS WEEK...GENERATING A NW SWELL THAT ARRIVES LATE
MONDAY/TUESDAY. IT IS TOO EARLY FOR SPECIFICS AS THE LOW HAS YET TO
DEVELOP...BUT RESULTANT SURF LOOKS TO REMAIN BELOW ADVISORY LEVEL
HEIGHTS ALONG N AND W FACING SHORES.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...BRAVENDER
AVIATION...EATON






000
FXHW60 PHFO 030152
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST TUE SEP 2 2014

.SYNOPSIS...
LIGHT TO MODERATE TRADE WINDS WILL CONTINUE FOR MUCH OF THE UPCOMING
WEEK. THE TRADES WILL FOCUS SHOWERS MAINLY ACROSS WINDWARD AREAS...
ESPECIALLY DURING NIGHTS AND MORNINGS...WITH SOME AFTERNOON SHOWERS
ACROSS LEEWARD SECTIONS AS WELL.

&&

.DISCUSSION...
WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL HIGH OVER/JUST SOUTH OF THE
STATE...WITH A SHORTWAVE TROUGH FAR TO THE NORTHWEST. AT THE
SURFACE...HIGH PRESSURE IS LOCATED FAR NORTH-NORTHEAST OF THE
STATE...WITH A RIDGE PASSING SEVERAL HUNDRED MILES TO OUR NORTH. LOW
PRESSURE...FORMER TC MARIE...IS FAR NORTHEAST OF THE STATE AND
MOVING GENERALLY WESTWARD. THE 00Z SOUNDING FROM LIHUE SHOWS A
SLIGHTLY LOWER AND STRONGER INVERSION NEAR 6KFT...WITH A
PRECIPITABLE WATER NEAR 1.4 INCHES. EARLY AFTERNOON MIMIC TOTAL
PRECIPITABLE WATER IMAGERY SHOWS AN AREA OF HIGHER MOISTURE
EXTENDING UP TO 200 MILES NORTHEAST AND EAST OF THE STATE...WITH
DRIER AIR FARTHER UPSTREAM.

THE PRESSURE GRADIENT ACROSS THE ISLANDS REMAINS ON THE LIGHT SIDE
DUE TO OUR SEPARATION FROM THE HIGH AND INFLUENCE FROM FORMER MARIE.
HOWEVER...TRADES HAVE BEEN STRONGER AND MORE WIDESPREAD TODAY
COMPARED TO YESTERDAY. THE GRADIENT BETWEEN BUOYS 51100 NORTHEAST OF
THE STATE AND 51004 SOUTHEAST OF THE STATE HAS RISEN BY UP TO A
MILLIBAR OVER THE PAST 24 HOURS. THE ASCAT IMAGERY FROM THIS MORNING
SHOWED WINDS HAVE INCREASED FURTHER SINCE LAST NIGHT...WITH 10-15
KNOTS OF WIND OVER THE WESTERN HALF OF THE STATE AND 15-20 KNOTS
OVER THE EASTERN HALF. THE HIGH RESOLUTION WRF FROM LAST NIGHT...AS
WELL AS THE 12Z/18Z GLOBAL MODELS...SHOW THE STRONGER WINDS
SPREADING WESTWARD ACROSS THE STATE THROUGH TONIGHT AS WELL.

AN AREA OF LOW CLOUDS IS CURRENTLY LOCATED NORTHEAST OF MAUI AND THE
BIG ISLAND...AND IS MOVING WESTWARD AT ABOUT 10 MPH. THESE CLOUDS
ARE AN INDICATOR OF THE HIGHER MOISTURE JUST UPSTREAM OF THE
STATE...AND WILL HELP TO ENHANCE TRADE WIND SHOWERS MAINLY ACROSS
WINDWARD SECTIONS TONIGHT INTO WEDNESDAY. WE HAVE RECEIVED A COUPLE
RAIN GAGE REPORTS OF RATES OVER 1 INCH PER HOUR ON THE BIG ISLAND
FROM SHOWERS THAT LOOK RELATIVELY INNOCUOUS. AS THIS AREA OF
MOISTURE MOVES THROUGH THE STATE TONIGHT...WE WILL REMAIN ON THE
LOOKOUT FOR POTENTIAL FOR LOCALIZED HEAVY RAIN IF SHOWERS BECOME
ANCHORED.

GFS FORECAST SOUNDINGS/MOISTURE PLOTS SHOW DRIER AND MORE STABLE
CONDITIONS SPREADING ACROSS THE ISLANDS DURING THE DAY ON
WEDNESDAY...WITH LOWER RAINFALL CHANCES. THERE SHOULD REMAIN ENOUGH
OF A STRONGER GRADIENT FOR TRADE WINDS TO DOMINATE...WITH LOCALIZED
SEA BREEZES CONFINED TO SHELTERED LEEWARD AREAS. EVEN WITH MORE
PERSISTENT TRADES...WE WILL LIKELY SEE INCREASED CLOUD BUILDUPS
ACROSS INTERIOR AND LEEWARD SECTIONS DURING THE AFTERNOON AND EARLY
EVENING.

BY THE END OF THE WEEK...BOTH GFS AND ECMWF CONTINUE TO SHOW A
TONGUE OF MOISTURE TRAILING FROM FORMER MARIE REACHING THE ISLANDS.
THE GFS IS FASTER/MORE AGGRESSIVE THAN THE ECMWF...BUT BOTH SHOW THE
AREA OF CLOUDS/MOISTURE CURRENTLY EXTENDING DOWN TO 25N BETWEEN
140W/150W REACHING THE ISLANDS LATE THURSDAY/FRIDAY. FORECAST
SOUNDINGS/CROSS SECTIONS SHOW INCREASING MOISTURE DEPTH BACK TO NEAR
10KFT. DURING THIS TIMEFRAME...WINDS MAY ALSO WEAKEN A BIT. THE
REMNANT OF MARIE WILL MOVE WESTWARD AND WEAKEN AS IT ENCROACHES UPON
THE RIDGE. THE GRADIENT ACROSS THE ISLANDS MAY WEAKEN
THURSDAY/FRIDAY...BEFORE STRENGTHENING FURTHER SATURDAY INTO SUNDAY
AS THE LOW DISSIPATES AND WE FEEL MORE OF A DIRECT IMPACT FROM THE
SURFACE HIGH.

&&

.AVIATION...
LIGHT TO MODERATE TRADES WILL CONTINUE OVER THE NEXT FEW DAYS. WINDS
SHOULD REMAIN LIGHT ENOUGH TO LIMIT THE NEED FOR A LOW LEVEL TURB
AIRMET. SHOWERS WILL FAVOR WINDWARD AND MAUKA AREAS...ESPECIALLY
OVERNIGHT AND EARLY MORNING. MVFR CONDITIONS ARE LIKELY WITHIN THESE
SHOWERS. OTHERWISE...VFR WILL PREVAIL.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
FORERUNNERS OF A VERY LONG PERIOD S SWELL /20-25 SECONDS/ THAT
ARRIVED EARLY TODAY ARE EXPECTED TO BUILD FURTHER TONIGHT...ALTHOUGH
AT LOW HEIGHTS. THE LARGEST PART OF THE SWELL WILL MISS US TO THE
EAST...AS SEEN BY THE GREATER LONG-PERIOD ENERGY THAT CONTINUES TO
INCREASE AT BUOY 51004 SOUTHEAST OF THE STATE VERSUS THE MUCH LOWER
ENERGY AT BUOY 51003 SOUTH OF THE STATE. LOCALLY...THE LATEST
OBSERVATIONS FROM THE CDIP BUOY AT BARBERS POINT SHOW INITIAL ENERGY
FROM THIS SWELL IS DOMINATED BY THE FADING SHORTER PERIOD SOUTH
SWELL. AS THIS NEW SWELL FILLS IN...IT WILL PRODUCE SURF NEAR
ADVISORY LEVELS ALONG S FACING SHORES FROM WEDNESDAY INTO THURSDAY.
WITH THE BULK OF THE ENERGY PASSING TO THE EAST...THE CURRENT
EXPECTATION IS THAT SURF WILL REMAIN JUST BELOW ADVISORY LEVELS FOR
SOUTH FACING SHORES. THEREFORE WE WILL HOLD OFF ON AN ADVISORY FOR
NOW...BUT WILL KEEP AN EYE ON CONDITIONS AS THEY BUILD THROUGH THE
NIGHT.

FORECAST MODELS SHOW A FAIRLY LARGE GALE LOW DEVELOPING NW OF THE
STATE THIS WEEK...GENERATING A NW SWELL THAT ARRIVES LATE
MONDAY/TUESDAY. IT IS TOO EARLY FOR SPECIFICS AS THE LOW HAS YET TO
DEVELOP...BUT RESULTANT SURF LOOKS TO REMAIN BELOW ADVISORY LEVEL
HEIGHTS ALONG N AND W FACING SHORES.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...BRAVENDER
AVIATION...EATON







000
FXHW60 PHFO 021947
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST TUE SEP 2 2014

.SYNOPSIS...
LIGHT TO MODERATE TRADE WINDS WILL CONTINUE FOR MUCH OF THE UPCOMING
WEEK. THE TRADES WILL FOCUS SHOWERS MAINLY ACROSS WINDWARD AREAS...
ESPECIALLY DURING NIGHTS AND MORNINGS...WITH SOME AFTERNOON SHOWERS
ACROSS LEEWARD SECTIONS AS WELL.

&&

.DISCUSSION...
WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL HIGH OVER/JUST SOUTH OF THE
STATE...WITH A SHORTWAVE TROUGH FAR TO THE NORTHWEST. AT THE
SURFACE...HIGH PRESSURE IS LOCATED FAR NORTH-NORTHEAST OF THE
STATE...WITH A RIDGE PASSING SEVERAL HUNDRED MILES TO OUR NORTH. LOW
PRESSURE...FORMER TC MARIE...IS FAR NORTHEAST OF THE STATE AND
MOVING GENERALLY WESTWARD. 12Z SOUNDINGS FROM HILO AND LIHUE SHOW
INVERSIONS RANGING FROM 7KFT AT LIHUE TO 10KFT AT HILO. PRECIPITABLE
WATERS ALSO RANGE FROM 1.4 TO 1.7 INCHES RESPECTIVELY. EARLY MORNING
MIMIC TOTAL PRECIPITABLE WATER IMAGERY SHOWS AN AREA OF HIGHER
MOISTURE EXTENDING UP TO 250 MILES NORTHEAST AND EAST OF THE
STATE...WITH DRIER AIR FARTHER UPSTREAM.

THE PRESSURE GRADIENT ACROSS THE ISLANDS REMAINS ON THE LIGHT SIDE
DUE TO OUR SEPARATION FROM THE HIGH AND INFLUENCE FROM FORMER MARIE.
HOWEVER...INDICATIONS ARE THAT TRADES ARE MORE ENTRENCHED THAN
YESTERDAY. THE GRADIENT BETWEEN BUOYS 51100 NORTHEAST OF THE STATE
AND 51004 SOUTHEAST OF THE STATE HAS RISEN BY OVER A MILLIBAR OVER
THE PAST 24 HOURS. THE ASCAT IMAGERY FROM LAST NIGHT SHOWED AROUND
10 KNOTS OF WIND NEAR KAUAI...10 TO 15 KNOTS NEAR OAHU AND MAUI
COUNTY...AND 15 TO 20 KNOTS NEAR THE BIG ISLAND. THE HIGH
RESOLUTION WRF FROM LAST NIGHT...AS WELL AS THE 12Z GLOBAL
MODELS...SHOW THE STRONGER WINDS SPREADING WESTWARD ACROSS THE STATE
TODAY/TONIGHT AS WELL. THERE MAY BE ENOUGH OF A STRONGER GRADIENT
FOR TRADE WINDS TO DOMINATE...WITH LOCALIZED SEA BREEZES CONFINED
TO SHELTERED LEEWARD AREAS. EVEN WITH MORE PERSISTENT TRADES...WE
WILL LIKELY SEE INCREASED CLOUD BUILDUPS ACROSS INTERIOR AND LEEWARD
SECTIONS DURING THE AFTERNOON AND EARLY EVENING.

AN AREA OF LOW CLOUDS IS CURRENTLY LOCATED NORTHEAST OF MAUI AND THE
BIG ISLAND...AND IS MOVING WESTWARD AT ABOUT 10 MPH. THESE CLOUDS
ARE AN INDICATOR OF THE HIGHER MOISTURE JUST UPSTREAM OF THE
STATE...AND WILL HELP TO ENHANCE TRADE WIND SHOWERS MAINLY ACROSS
WINDWARD SECTIONS TONIGHT INTO WEDNESDAY. GFS FORECAST
SOUNDINGS/MOISTURE PLOTS SHOW DRIER AND MORE STABLE CONDITIONS
SPREADING ACROSS THE ISLANDS DURING THE DAY ON WEDNESDAY...WITH
LOWER RAINFALL CHANCES.

BY THE END OF THE WEEK...BOTH GFS AND ECMWF CONTINUE TO SHOW A
TONGUE OF MOISTURE TRAILING FROM FORMER MARIE REACHING THE ISLANDS.
THE GFS IS FASTER/MORE AGGRESSIVE THAN THE ECMWF...BUT BOTH SHOW THE
AREA OF CLOUDS/MOISTURE CURRENTLY EXTENDING DOWN TO 25N BETWEEN
140W/150W REACHING THE ISLANDS LATE THURSDAY/FRIDAY. FORECAST
SOUNDINGS/CROSS SECTIONS SHOW INCREASING MOISTURE DEPTH BACK TO NEAR
10KFT. DURING THIS TIMEFRAME...WINDS MAY ALSO WEAKEN A BIT. THE
REMNANT OF MARIE WILL MOVE WESTWARD AND WEAKEN AS IT ENCROACHES UPON
THE RIDGE. THE GRADIENT ACROSS THE ISLANDS MAY WEAKEN
THURSDAY/FRIDAY...BEFORE STRENGTHENING FURTHER SATURDAY INTO SUNDAY
AS THE LOW DISSIPATES AND WE FEEL MORE OF A DIRECT IMPACT FROM THE
SURFACE HIGH.

&&

.AVIATION...
THROUGHOUT THE DAY...TRADE WINDS WILL GRADUALLY BEGIN TO BUILD BACK.
ISOL MVFR OVER WINDWARD AND MOUNTAIN AREAS MAY OCCUR IN PASSING
SHOWERS. OTHERWISE...VFR CONDITIONS WILL PREVAIL. THERE ARE NO
AIRMETS IN EFFECT.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
ALTHOUGH SURF IS CURRENTLY BELOW ADVISORY LEVELS...FORERUNNERS OF A
VERY LONG PERIOD S SWELL /20-25 SECONDS/ ARE EXPECTED TO BUILD TODAY
AND TONIGHT...ALTHOUGH AT LOW HEIGHTS. LATEST OBSERVATIONS FROM THE
CDIP BUOY AT BARBERS POINT SHOW INITIAL ENERGY FROM THIS SWELL IS
BEGINNING TO ARRIVE...BUT THE BULK OF THE SWELL ENERGY IS DOMINATED
BY THE FADING SHORTER PERIOD SOUTH SWELL. AS THIS NEW SWELL FILLS
IN...IT WILL PRODUCE SURF NEAR ADVISORY LEVELS ALONG S FACING
SHORES...LIKELY FROM WEDNESDAY INTO THURSDAY. WILL HOLD OFF ON THE
ISSUANCE OF AN ADVISORY TO SEE IF BUOY DATA SHOWS GREATER AMPLITUDE
SWELL HEIGHTS...BUT AN ADVISORY MAY BE NECESSARY THIS AFTERNOON FOR
SURF NEARING ADVISORY LEVELS ON WEDNESDAY.

FORECAST MODELS SHOW A FAIRLY LARGE GALE LOW DEVELOPING NW OF THE
STATE THIS WEEK...GENERATING A NW SWELL THAT ARRIVES LATE
MONDAY/TUESDAY. IT IS TOO EARLY FOR SPECIFICS AS THE LOW HAS YET TO
DEVELOP...BUT RESULTANT SURF LOOKS TO REMAIN BELOW ADVISORY LEVEL
HEIGHTS ALONG N AND W FACING SHORES.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...BRAVENDER
AVIATION...EATON







000
FXHW60 PHFO 021947
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST TUE SEP 2 2014

.SYNOPSIS...
LIGHT TO MODERATE TRADE WINDS WILL CONTINUE FOR MUCH OF THE UPCOMING
WEEK. THE TRADES WILL FOCUS SHOWERS MAINLY ACROSS WINDWARD AREAS...
ESPECIALLY DURING NIGHTS AND MORNINGS...WITH SOME AFTERNOON SHOWERS
ACROSS LEEWARD SECTIONS AS WELL.

&&

.DISCUSSION...
WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL HIGH OVER/JUST SOUTH OF THE
STATE...WITH A SHORTWAVE TROUGH FAR TO THE NORTHWEST. AT THE
SURFACE...HIGH PRESSURE IS LOCATED FAR NORTH-NORTHEAST OF THE
STATE...WITH A RIDGE PASSING SEVERAL HUNDRED MILES TO OUR NORTH. LOW
PRESSURE...FORMER TC MARIE...IS FAR NORTHEAST OF THE STATE AND
MOVING GENERALLY WESTWARD. 12Z SOUNDINGS FROM HILO AND LIHUE SHOW
INVERSIONS RANGING FROM 7KFT AT LIHUE TO 10KFT AT HILO. PRECIPITABLE
WATERS ALSO RANGE FROM 1.4 TO 1.7 INCHES RESPECTIVELY. EARLY MORNING
MIMIC TOTAL PRECIPITABLE WATER IMAGERY SHOWS AN AREA OF HIGHER
MOISTURE EXTENDING UP TO 250 MILES NORTHEAST AND EAST OF THE
STATE...WITH DRIER AIR FARTHER UPSTREAM.

THE PRESSURE GRADIENT ACROSS THE ISLANDS REMAINS ON THE LIGHT SIDE
DUE TO OUR SEPARATION FROM THE HIGH AND INFLUENCE FROM FORMER MARIE.
HOWEVER...INDICATIONS ARE THAT TRADES ARE MORE ENTRENCHED THAN
YESTERDAY. THE GRADIENT BETWEEN BUOYS 51100 NORTHEAST OF THE STATE
AND 51004 SOUTHEAST OF THE STATE HAS RISEN BY OVER A MILLIBAR OVER
THE PAST 24 HOURS. THE ASCAT IMAGERY FROM LAST NIGHT SHOWED AROUND
10 KNOTS OF WIND NEAR KAUAI...10 TO 15 KNOTS NEAR OAHU AND MAUI
COUNTY...AND 15 TO 20 KNOTS NEAR THE BIG ISLAND. THE HIGH
RESOLUTION WRF FROM LAST NIGHT...AS WELL AS THE 12Z GLOBAL
MODELS...SHOW THE STRONGER WINDS SPREADING WESTWARD ACROSS THE STATE
TODAY/TONIGHT AS WELL. THERE MAY BE ENOUGH OF A STRONGER GRADIENT
FOR TRADE WINDS TO DOMINATE...WITH LOCALIZED SEA BREEZES CONFINED
TO SHELTERED LEEWARD AREAS. EVEN WITH MORE PERSISTENT TRADES...WE
WILL LIKELY SEE INCREASED CLOUD BUILDUPS ACROSS INTERIOR AND LEEWARD
SECTIONS DURING THE AFTERNOON AND EARLY EVENING.

AN AREA OF LOW CLOUDS IS CURRENTLY LOCATED NORTHEAST OF MAUI AND THE
BIG ISLAND...AND IS MOVING WESTWARD AT ABOUT 10 MPH. THESE CLOUDS
ARE AN INDICATOR OF THE HIGHER MOISTURE JUST UPSTREAM OF THE
STATE...AND WILL HELP TO ENHANCE TRADE WIND SHOWERS MAINLY ACROSS
WINDWARD SECTIONS TONIGHT INTO WEDNESDAY. GFS FORECAST
SOUNDINGS/MOISTURE PLOTS SHOW DRIER AND MORE STABLE CONDITIONS
SPREADING ACROSS THE ISLANDS DURING THE DAY ON WEDNESDAY...WITH
LOWER RAINFALL CHANCES.

BY THE END OF THE WEEK...BOTH GFS AND ECMWF CONTINUE TO SHOW A
TONGUE OF MOISTURE TRAILING FROM FORMER MARIE REACHING THE ISLANDS.
THE GFS IS FASTER/MORE AGGRESSIVE THAN THE ECMWF...BUT BOTH SHOW THE
AREA OF CLOUDS/MOISTURE CURRENTLY EXTENDING DOWN TO 25N BETWEEN
140W/150W REACHING THE ISLANDS LATE THURSDAY/FRIDAY. FORECAST
SOUNDINGS/CROSS SECTIONS SHOW INCREASING MOISTURE DEPTH BACK TO NEAR
10KFT. DURING THIS TIMEFRAME...WINDS MAY ALSO WEAKEN A BIT. THE
REMNANT OF MARIE WILL MOVE WESTWARD AND WEAKEN AS IT ENCROACHES UPON
THE RIDGE. THE GRADIENT ACROSS THE ISLANDS MAY WEAKEN
THURSDAY/FRIDAY...BEFORE STRENGTHENING FURTHER SATURDAY INTO SUNDAY
AS THE LOW DISSIPATES AND WE FEEL MORE OF A DIRECT IMPACT FROM THE
SURFACE HIGH.

&&

.AVIATION...
THROUGHOUT THE DAY...TRADE WINDS WILL GRADUALLY BEGIN TO BUILD BACK.
ISOL MVFR OVER WINDWARD AND MOUNTAIN AREAS MAY OCCUR IN PASSING
SHOWERS. OTHERWISE...VFR CONDITIONS WILL PREVAIL. THERE ARE NO
AIRMETS IN EFFECT.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
ALTHOUGH SURF IS CURRENTLY BELOW ADVISORY LEVELS...FORERUNNERS OF A
VERY LONG PERIOD S SWELL /20-25 SECONDS/ ARE EXPECTED TO BUILD TODAY
AND TONIGHT...ALTHOUGH AT LOW HEIGHTS. LATEST OBSERVATIONS FROM THE
CDIP BUOY AT BARBERS POINT SHOW INITIAL ENERGY FROM THIS SWELL IS
BEGINNING TO ARRIVE...BUT THE BULK OF THE SWELL ENERGY IS DOMINATED
BY THE FADING SHORTER PERIOD SOUTH SWELL. AS THIS NEW SWELL FILLS
IN...IT WILL PRODUCE SURF NEAR ADVISORY LEVELS ALONG S FACING
SHORES...LIKELY FROM WEDNESDAY INTO THURSDAY. WILL HOLD OFF ON THE
ISSUANCE OF AN ADVISORY TO SEE IF BUOY DATA SHOWS GREATER AMPLITUDE
SWELL HEIGHTS...BUT AN ADVISORY MAY BE NECESSARY THIS AFTERNOON FOR
SURF NEARING ADVISORY LEVELS ON WEDNESDAY.

FORECAST MODELS SHOW A FAIRLY LARGE GALE LOW DEVELOPING NW OF THE
STATE THIS WEEK...GENERATING A NW SWELL THAT ARRIVES LATE
MONDAY/TUESDAY. IT IS TOO EARLY FOR SPECIFICS AS THE LOW HAS YET TO
DEVELOP...BUT RESULTANT SURF LOOKS TO REMAIN BELOW ADVISORY LEVEL
HEIGHTS ALONG N AND W FACING SHORES.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...BRAVENDER
AVIATION...EATON






000
FXHW60 PHFO 021401
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST TUE SEP 2 2014

.SYNOPSIS...
LIGHT TRADE WINDS WILL STRENGTHEN SLIGHTLY TODAY...AND REMAIN LIGHT
TO MODERATE FOR MOST OF THE UPCOMING WEEK. THE TRADE WINDS WILL
DELIVER A FEW SHOWERS TO WINDWARD AREAS...ESPECIALLY DURING NIGHTS
AND MORNINGS.

&&

.DISCUSSION...
LATEST OBSERVATIONS SHOW THAT A LIGHT EASTERLY FLOW PREVAILS IN THE
LOW LEVELS...WITH WINDS LIGHT ENOUGH TO ALLOW LOCALIZED LAND BREEZES.
THE WINDS ARE BEING SUPPORTED BY A DISTANT HIGH THAT IS RELATIVELY
WEAK...WITH WEAK TROUGHS BETWEEN THE HIGH AND THE ISLANDS
CONTRIBUTING TO A LOOSE PRESSURE GRADIENT...AS IS THE NEARLY
STATIONARY REMNANT CIRCULATION OF MARIE...ABOUT 1300 MILES NE OF
THE ISLANDS. ALTHOUGH SKIES IMMEDIATELY UPSTREAM OF THE ISLANDS FROM
KAUAI TO MOLOKAI CONTAIN ONLY ISOLATED SHOWERS...AN AREA OF SHOWERY
LOW CLOUDS LIES OVER WINDWARD WATERS OUT TO 200 MILES E OF MAUI AND
THE BIG ISLAND...MOVING W AT 10 TO 15 MPH.

TODAY...ABUNDANT SUNSHINE IS EXPECTED OVER LEEWARD AREAS...WHILE
WINDWARD AREAS WILL BE PARTLY CLOUDY WITH A FEW BRIEF SHOWERS.
SHOWERS/CLOUDS ARE EXPECTED TO BE A LITTLE MORE ACTIVE THROUGH
TONIGHT OVER WINDWARD MAUI AND BIG ISLAND AS THE AFOREMENTIONED AREA
OF MOISTURE MOVES W. AFTER THIS MODEST MOISTURE SOURCE PASSES...
LIMITED MOISTURE IS EXPECTED THROUGH THURSDAY. INCREASED MOISTURE
LOOSELY ASSOCIATED WITH THE REMNANT OF MARIE PASSING FAR NE OF THE
ISLANDS MAY INCREASE WINDWARD SHOWERS FROM THURSDAY NIGHT THROUGH
SATURDAY. A MID-LEVEL RIDGE NEAR THE ISLANDS WILL ENSURE THAT THE
ATMOSPHERE REMAINS STRONGLY CAPPED AT ABOUT 8 TO 10 KFT.

TRADE WINDS ARE EXPECTED TO BE SLIGHTLY STRONGER TODAY AS COMPARED
TO THE LAST 2 DAYS...AS THE TROUGHS NW OF THE ISLANDS WEAKEN AND THE
SURFACE RIDGE TO THE N STRENGTHENS SOMEWHAT. THE OVERALL SYNOPTIC
PATTERN DOES NOT SUPPORT A STRONG TRADE FLOW THIS WEEK HOWEVER...BUT
RATHER A LIGHT TO MODERATE FLOW. THEREFORE...ONE OF THE BIGGEST
FORECAST QUESTIONS OVER THE NEXT COUPLE OF DAYS INVOLVES THE
STRENGTH OF THE TRADE WINDS...AND WHETHER OR NOT AFTERNOON SEA
BREEZES WILL BECOME SUFFICIENTLY STRONG/WIDESPREAD TO DRIVE CLOUD
AND SHOWER DEVELOPMENT OVER LEEWARD AND INTERIOR AREAS. ALTHOUGH A
SLIGHT INCREASE IN LEEWARD SKY COVER IS IN THE FORECAST GRIDS FOR
THE SMALLER ISLANDS TODAY...NO SIGNIFICANT POPS ARE INDICATED. SOME
UNCERTAINTY AS TO HOW THIS WILL VERIFY. THE LEEWARD BIG ISLAND IS
THE EXCEPTION...WHERE LEEWARD CLOUDS AND SHOWERS ARE EXPECTED EVERY
AFTERNOON AND EVENING THROUGH THE FORECAST PERIOD.

&&

.AVIATION...
WINDWARD AND MOUNTAIN AREAS MAY EXPERIENCE BRIEF MVFR CONDITIONS AS
WEAK TRADE WIND FLOW PUSHES A FEW SHOWERS ASHORE...ESPECIALLY OVER
THE EASTERN END OF THE ISLAND CHAIN. NO AIRMETS IN EFFECT.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
ALTHOUGH SURF IS CURRENTLY BELOW ADVISORY LEVELS...FORERUNNERS OF A
VERY LONG PERIOD S SWELL /20-25 SECONDS/ ARE EXPECTED TO BUILD TODAY
AND TONIGHT...ALTHOUGH AT LOW HEIGHTS. LATEST OBSERVATIONS FROM BUOY
51004 AND THE CDIP BUOY AT BARBERS POINT SHOW INITIAL ENERGY FROM
THIS SWELL IS BEGINNING TO ARRIVE. AS THIS SWELL FILLS IN...IT WILL
PRODUCE SURF NEAR ADVISORY LEVELS ALONG S FACING SHORES...LIKELY
FROM WEDNESDAY INTO THURSDAY. WILL HOLD OFF ON THE ISSUANCE OF AN
ADVISORY TO SEE IF BUOY DATA SHOWS GREATER AMPLITUDE SWELL
HEIGHTS...BUT AN ADVISORY MAY BE NECESSARY LATER TODAY FOR SURF
NEARING ADVISORY LEVELS ON WEDNESDAY.

FORECAST MODELS ARE INDICATING THAT A FAIRLY LARGE GALE LOW WILL
DEVELOP NW OF THE ISLANDS THIS WEEK...GENERATING A NW SWELL THAT
ARRIVES AROUND MONDAY. SINCE THE LOW HAS YET TO DEVELOP...TOO
EARLY FOR SPECIFICS...BUT RESULTANT SURF LOOKS TO REMAIN BELOW
ADVISORY LEVEL HEIGHTS ALONG N AND W FACING SHORES.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS
AT LEAST FOR THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

BIRCHARD







000
FXHW60 PHFO 021401
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST TUE SEP 2 2014

.SYNOPSIS...
LIGHT TRADE WINDS WILL STRENGTHEN SLIGHTLY TODAY...AND REMAIN LIGHT
TO MODERATE FOR MOST OF THE UPCOMING WEEK. THE TRADE WINDS WILL
DELIVER A FEW SHOWERS TO WINDWARD AREAS...ESPECIALLY DURING NIGHTS
AND MORNINGS.

&&

.DISCUSSION...
LATEST OBSERVATIONS SHOW THAT A LIGHT EASTERLY FLOW PREVAILS IN THE
LOW LEVELS...WITH WINDS LIGHT ENOUGH TO ALLOW LOCALIZED LAND BREEZES.
THE WINDS ARE BEING SUPPORTED BY A DISTANT HIGH THAT IS RELATIVELY
WEAK...WITH WEAK TROUGHS BETWEEN THE HIGH AND THE ISLANDS
CONTRIBUTING TO A LOOSE PRESSURE GRADIENT...AS IS THE NEARLY
STATIONARY REMNANT CIRCULATION OF MARIE...ABOUT 1300 MILES NE OF
THE ISLANDS. ALTHOUGH SKIES IMMEDIATELY UPSTREAM OF THE ISLANDS FROM
KAUAI TO MOLOKAI CONTAIN ONLY ISOLATED SHOWERS...AN AREA OF SHOWERY
LOW CLOUDS LIES OVER WINDWARD WATERS OUT TO 200 MILES E OF MAUI AND
THE BIG ISLAND...MOVING W AT 10 TO 15 MPH.

TODAY...ABUNDANT SUNSHINE IS EXPECTED OVER LEEWARD AREAS...WHILE
WINDWARD AREAS WILL BE PARTLY CLOUDY WITH A FEW BRIEF SHOWERS.
SHOWERS/CLOUDS ARE EXPECTED TO BE A LITTLE MORE ACTIVE THROUGH
TONIGHT OVER WINDWARD MAUI AND BIG ISLAND AS THE AFOREMENTIONED AREA
OF MOISTURE MOVES W. AFTER THIS MODEST MOISTURE SOURCE PASSES...
LIMITED MOISTURE IS EXPECTED THROUGH THURSDAY. INCREASED MOISTURE
LOOSELY ASSOCIATED WITH THE REMNANT OF MARIE PASSING FAR NE OF THE
ISLANDS MAY INCREASE WINDWARD SHOWERS FROM THURSDAY NIGHT THROUGH
SATURDAY. A MID-LEVEL RIDGE NEAR THE ISLANDS WILL ENSURE THAT THE
ATMOSPHERE REMAINS STRONGLY CAPPED AT ABOUT 8 TO 10 KFT.

TRADE WINDS ARE EXPECTED TO BE SLIGHTLY STRONGER TODAY AS COMPARED
TO THE LAST 2 DAYS...AS THE TROUGHS NW OF THE ISLANDS WEAKEN AND THE
SURFACE RIDGE TO THE N STRENGTHENS SOMEWHAT. THE OVERALL SYNOPTIC
PATTERN DOES NOT SUPPORT A STRONG TRADE FLOW THIS WEEK HOWEVER...BUT
RATHER A LIGHT TO MODERATE FLOW. THEREFORE...ONE OF THE BIGGEST
FORECAST QUESTIONS OVER THE NEXT COUPLE OF DAYS INVOLVES THE
STRENGTH OF THE TRADE WINDS...AND WHETHER OR NOT AFTERNOON SEA
BREEZES WILL BECOME SUFFICIENTLY STRONG/WIDESPREAD TO DRIVE CLOUD
AND SHOWER DEVELOPMENT OVER LEEWARD AND INTERIOR AREAS. ALTHOUGH A
SLIGHT INCREASE IN LEEWARD SKY COVER IS IN THE FORECAST GRIDS FOR
THE SMALLER ISLANDS TODAY...NO SIGNIFICANT POPS ARE INDICATED. SOME
UNCERTAINTY AS TO HOW THIS WILL VERIFY. THE LEEWARD BIG ISLAND IS
THE EXCEPTION...WHERE LEEWARD CLOUDS AND SHOWERS ARE EXPECTED EVERY
AFTERNOON AND EVENING THROUGH THE FORECAST PERIOD.

&&

.AVIATION...
WINDWARD AND MOUNTAIN AREAS MAY EXPERIENCE BRIEF MVFR CONDITIONS AS
WEAK TRADE WIND FLOW PUSHES A FEW SHOWERS ASHORE...ESPECIALLY OVER
THE EASTERN END OF THE ISLAND CHAIN. NO AIRMETS IN EFFECT.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
ALTHOUGH SURF IS CURRENTLY BELOW ADVISORY LEVELS...FORERUNNERS OF A
VERY LONG PERIOD S SWELL /20-25 SECONDS/ ARE EXPECTED TO BUILD TODAY
AND TONIGHT...ALTHOUGH AT LOW HEIGHTS. LATEST OBSERVATIONS FROM BUOY
51004 AND THE CDIP BUOY AT BARBERS POINT SHOW INITIAL ENERGY FROM
THIS SWELL IS BEGINNING TO ARRIVE. AS THIS SWELL FILLS IN...IT WILL
PRODUCE SURF NEAR ADVISORY LEVELS ALONG S FACING SHORES...LIKELY
FROM WEDNESDAY INTO THURSDAY. WILL HOLD OFF ON THE ISSUANCE OF AN
ADVISORY TO SEE IF BUOY DATA SHOWS GREATER AMPLITUDE SWELL
HEIGHTS...BUT AN ADVISORY MAY BE NECESSARY LATER TODAY FOR SURF
NEARING ADVISORY LEVELS ON WEDNESDAY.

FORECAST MODELS ARE INDICATING THAT A FAIRLY LARGE GALE LOW WILL
DEVELOP NW OF THE ISLANDS THIS WEEK...GENERATING A NW SWELL THAT
ARRIVES AROUND MONDAY. SINCE THE LOW HAS YET TO DEVELOP...TOO
EARLY FOR SPECIFICS...BUT RESULTANT SURF LOOKS TO REMAIN BELOW
ADVISORY LEVEL HEIGHTS ALONG N AND W FACING SHORES.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS
AT LEAST FOR THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

BIRCHARD






000
FXHW60 PHFO 020651
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
850 PM HST MON SEP 1 2014

.SYNOPSIS...
LIGHT TRADE WINDS WILL STRENGTHEN SLIGHTLY ON TUESDAY...AND REMAIN
LIGHT TO MODERATE FOR MOST OF THE UPCOMING WEEK. THE LIGHT WINDS
WILL ALLOW LAND BREEZES TO DEVELOP OVER LEEWARD AREAS LATER TONIGHT
AS THE LAND COOLS...RESULTING IN CLEARING SKIES. MEANWHILE...THE
LIGHT TRADE WINDS WILL DELIVER A FEW SHOWERS TO WINDWARD AREAS.
WITH THE STRENGTHENING TRADES...EXPECT CLOUDS AND SHOWERS TO FAVOR
WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LATEST SATELLITE AND RADAR ANIMATIONS SHOW THE LOW-LEVEL FLOW IS
FROM THE E...AT LEAST AT CLOUD LEVEL...PUSHING LIMITED CLOUDS AND
SHOWERS OVER NEAR SHORE WATERS TOWARD THE W. AN AREA OF ENHANCED
SHOWERS IS LINGERING OVER WINDWARD OAHU AND NEAR SHORE WATERS...AS
REMNANTS OF AFTERNOON CONVECTION INTERACT WITH THE LIGHT E WINDS.
THE WINDS ARE BEING SUPPORTED BY A DISTANT HIGH THAT IS RELATIVELY
WEAK...WITH WEAK TROUGHS BETWEEN THE HIGH AND THE ISLANDS
CONTRIBUTING TO A LOOSE PRESSURE GRADIENT...AS IS THE REMNANT
CIRCULATION OF MARIE ABOUT 1300 MILES NE OF THE ISLANDS. ALTHOUGH
SKIES IMMEDIATELY UPSTREAM OF THE ISLANDS ARE NEARLY CLEAR...AN AREA
OF SHOWERY LOW CLOUDS LIES 100 TO 300 MILES E OF WINDWARD BIG
ISLAND...MOVING W NEAR 10 MPH.

OVERNIGHT...LINGERING SEA BREEZE-DRIVEN CLOUDS AND SHOWERS OVER
KAUAI AND OAHU WILL GRADUALLY DIMINISH...WHILE THE LIGHT TRADE WINDS
DELIVER A FEW SHOWERS TO WINDWARD AREAS STATEWIDE. LEEWARD AREAS ON
ALL ISLANDS WILL SEE CLEAR SKIES DEVELOPING...WITH THE LIGHT TRADES
ALLOWING LAND BREEZES TO DEVELOP IN SHELTERED AREAS.

WINDS WILL SLOWLY STRENGTHEN ON TUESDAY AS THE TROUGHS NW OF THE
ISLANDS WEAKEN AND THE SURFACE RIDGE TO THE N STRENGTHENS SOMEWHAT.
THE OVERALL SYNOPTIC PATTERN DOES NOT SUPPORT A STRONG TRADE FLOW
THIS WEEK HOWEVER...BUT RATHER A LIGHT TO MODERATE FLOW. THE TRADE
WINDS WILL PUSH THE AREA OF MOISTURE E OF THE BIG ISLAND OVER THE
ISLAND CHAIN OVER THE 12 TO 36 HOURS...WITH LATEST GUIDANCE
SUGGESTING IT WILL MOVE OVER WINDWARD BIG ISLAND BY TUESDAY
MORNING...MAUI COUNTY DURING THE DAY...OAHU BY EVENING AND KAUAI BY
TUESDAY NIGHT BEFORE CLEARING TO THE W. AFTER THIS MODEST MOISTURE
SOURCE PASSES...LIMITED MOISTURE IS EXPECTED THROUGH THURSDAY.
INCREASED MOISTURE LOOSELY ASSOCIATED WITH THE REMNANT OF MARIE
PASSING FAR NE OF THE ISLANDS MAY INCREASE WINDWARD SHOWERS FROM
THURSDAY NIGHT THROUGH SATURDAY.

BIGGEST FORECAST QUESTION FOR THE NEXT COUPLE OF DAYS INVOLVES THE
STRENGTH OF THE TRADE WINDS...AND WHETHER OR NOR LEEWARD SEA BREEZES
WILL BECOME STRONG ENOUGH TO LEAD TO CLOUD AND SHOWER DEVELOPMENT
OVER LEEWARD AND INTERIOR AREAS...SIMILAR TO WHAT WE SAW ON KAUAI
AND OAHU TODAY. LATEST FORECAST GRIDS DO NOT INDICATE THAT THIS WILL
OCCUR...AND WILL MONITOR OVERNIGHT TRENDS AND MODEL GUIDANCE TO SEE
IF A CHANCE OF AFTERNOON LEEWARD SHOWERS SHOULD BE INCLUDED IN THE
FORECAST. NEEDLESS TO SAY...THE LEEWARD BIG ISLAND IS THE
EXCEPTION...WITH LEEWARD CLOUDS AND SHOWERS BE EXPECTED EVERY
AFTERNOON AND EVENING THROUGH THE FORECAST PERIOD.

&&

.AVIATION...
WINDWARD AND MOUNTAIN AREAS MAY EXPERIENCE ISOL MVFR CONDITIONS AS
WEAK TRADE WIND FLOW PUSHES A FEW SHRA ASHORE. THERE ARE NO AIRMETS
IN EFFECT.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
ALTHOUGH SURF IS CURRENTLY BELOW ADVISORY LEVELS...FORERUNNERS OF A
VERY LONG PERIOD S SWELL /20-25 SECONDS/ ARE EXPECTED TO BEGIN
ARRIVING OVERNIGHT...ALTHOUGH AT LOW HEIGHTS. AS THIS SWELL FILLS
IN...IT WILL PRODUCE SURF NEAR ADVISORY LEVELS ALONG S FACING
SHORES...LIKELY FROM EARLY WEDNESDAY INTO THURSDAY.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS
AT LEAST FOR THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

BIRCHARD






000
FXHW60 PHFO 020651
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
850 PM HST MON SEP 1 2014

.SYNOPSIS...
LIGHT TRADE WINDS WILL STRENGTHEN SLIGHTLY ON TUESDAY...AND REMAIN
LIGHT TO MODERATE FOR MOST OF THE UPCOMING WEEK. THE LIGHT WINDS
WILL ALLOW LAND BREEZES TO DEVELOP OVER LEEWARD AREAS LATER TONIGHT
AS THE LAND COOLS...RESULTING IN CLEARING SKIES. MEANWHILE...THE
LIGHT TRADE WINDS WILL DELIVER A FEW SHOWERS TO WINDWARD AREAS.
WITH THE STRENGTHENING TRADES...EXPECT CLOUDS AND SHOWERS TO FAVOR
WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LATEST SATELLITE AND RADAR ANIMATIONS SHOW THE LOW-LEVEL FLOW IS
FROM THE E...AT LEAST AT CLOUD LEVEL...PUSHING LIMITED CLOUDS AND
SHOWERS OVER NEAR SHORE WATERS TOWARD THE W. AN AREA OF ENHANCED
SHOWERS IS LINGERING OVER WINDWARD OAHU AND NEAR SHORE WATERS...AS
REMNANTS OF AFTERNOON CONVECTION INTERACT WITH THE LIGHT E WINDS.
THE WINDS ARE BEING SUPPORTED BY A DISTANT HIGH THAT IS RELATIVELY
WEAK...WITH WEAK TROUGHS BETWEEN THE HIGH AND THE ISLANDS
CONTRIBUTING TO A LOOSE PRESSURE GRADIENT...AS IS THE REMNANT
CIRCULATION OF MARIE ABOUT 1300 MILES NE OF THE ISLANDS. ALTHOUGH
SKIES IMMEDIATELY UPSTREAM OF THE ISLANDS ARE NEARLY CLEAR...AN AREA
OF SHOWERY LOW CLOUDS LIES 100 TO 300 MILES E OF WINDWARD BIG
ISLAND...MOVING W NEAR 10 MPH.

OVERNIGHT...LINGERING SEA BREEZE-DRIVEN CLOUDS AND SHOWERS OVER
KAUAI AND OAHU WILL GRADUALLY DIMINISH...WHILE THE LIGHT TRADE WINDS
DELIVER A FEW SHOWERS TO WINDWARD AREAS STATEWIDE. LEEWARD AREAS ON
ALL ISLANDS WILL SEE CLEAR SKIES DEVELOPING...WITH THE LIGHT TRADES
ALLOWING LAND BREEZES TO DEVELOP IN SHELTERED AREAS.

WINDS WILL SLOWLY STRENGTHEN ON TUESDAY AS THE TROUGHS NW OF THE
ISLANDS WEAKEN AND THE SURFACE RIDGE TO THE N STRENGTHENS SOMEWHAT.
THE OVERALL SYNOPTIC PATTERN DOES NOT SUPPORT A STRONG TRADE FLOW
THIS WEEK HOWEVER...BUT RATHER A LIGHT TO MODERATE FLOW. THE TRADE
WINDS WILL PUSH THE AREA OF MOISTURE E OF THE BIG ISLAND OVER THE
ISLAND CHAIN OVER THE 12 TO 36 HOURS...WITH LATEST GUIDANCE
SUGGESTING IT WILL MOVE OVER WINDWARD BIG ISLAND BY TUESDAY
MORNING...MAUI COUNTY DURING THE DAY...OAHU BY EVENING AND KAUAI BY
TUESDAY NIGHT BEFORE CLEARING TO THE W. AFTER THIS MODEST MOISTURE
SOURCE PASSES...LIMITED MOISTURE IS EXPECTED THROUGH THURSDAY.
INCREASED MOISTURE LOOSELY ASSOCIATED WITH THE REMNANT OF MARIE
PASSING FAR NE OF THE ISLANDS MAY INCREASE WINDWARD SHOWERS FROM
THURSDAY NIGHT THROUGH SATURDAY.

BIGGEST FORECAST QUESTION FOR THE NEXT COUPLE OF DAYS INVOLVES THE
STRENGTH OF THE TRADE WINDS...AND WHETHER OR NOR LEEWARD SEA BREEZES
WILL BECOME STRONG ENOUGH TO LEAD TO CLOUD AND SHOWER DEVELOPMENT
OVER LEEWARD AND INTERIOR AREAS...SIMILAR TO WHAT WE SAW ON KAUAI
AND OAHU TODAY. LATEST FORECAST GRIDS DO NOT INDICATE THAT THIS WILL
OCCUR...AND WILL MONITOR OVERNIGHT TRENDS AND MODEL GUIDANCE TO SEE
IF A CHANCE OF AFTERNOON LEEWARD SHOWERS SHOULD BE INCLUDED IN THE
FORECAST. NEEDLESS TO SAY...THE LEEWARD BIG ISLAND IS THE
EXCEPTION...WITH LEEWARD CLOUDS AND SHOWERS BE EXPECTED EVERY
AFTERNOON AND EVENING THROUGH THE FORECAST PERIOD.

&&

.AVIATION...
WINDWARD AND MOUNTAIN AREAS MAY EXPERIENCE ISOL MVFR CONDITIONS AS
WEAK TRADE WIND FLOW PUSHES A FEW SHRA ASHORE. THERE ARE NO AIRMETS
IN EFFECT.

&&

.MARINE...
ELEVATED SURF WILL CONTINUE ALONG S FACING SHORES THIS WEEK.
ALTHOUGH SURF IS CURRENTLY BELOW ADVISORY LEVELS...FORERUNNERS OF A
VERY LONG PERIOD S SWELL /20-25 SECONDS/ ARE EXPECTED TO BEGIN
ARRIVING OVERNIGHT...ALTHOUGH AT LOW HEIGHTS. AS THIS SWELL FILLS
IN...IT WILL PRODUCE SURF NEAR ADVISORY LEVELS ALONG S FACING
SHORES...LIKELY FROM EARLY WEDNESDAY INTO THURSDAY.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS
AT LEAST FOR THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

BIRCHARD







000
FXHW60 PHFO 020203
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST MON SEP 1 2014

.SYNOPSIS...
LIGHT WINDS WILL ALLOW LAND BREEZES TO DEVELOP LATER TONIGHT AS THE
LAND COOLS...RESULTING IN CLEARING SKIES OVERNIGHT. SLIGHTLY
STRONGER TRADES ARE EXPECTED TO BUILD IN THE NEXT FEW DAYS AS A HIGH
PRESSURE RIDGE EXTENDS NORTH OF THE ISLANDS. WITH THE STRENGTHENING
TRADES...EXPECT THE CLOUDS AND SHOWERS TO BE FOCUSED MORE OVER THE
WINDWARD SLOPES.

&&

.DISCUSSION...
AFTERNOON CONVECTION BUILT OVER THE ISLAND THIS AFTERNOON AS
EXPECTED...WITH LOCALIZED SHOWERS...RATHER HEAVY OVER WINDWARD OAHU
IN THE PAST HOUR. A FEW GAGES REPORTED ALMOST HALF AN INCH OF RAIN
IN THE PAST FIFTEEN MINUTES. THEREFORE HAVE ISSUED A FLOOD ADVISORY
FOR WINDWARD OAHU AT TIME. EXPECT THE CONVECTION TO PEAK IN THE NEXT
FEW HOURS...THEN SLOWLY DISSIPATES AFTER SUNSET. SEA BREEZES PRETTY
MUCH DOMINATE THE ISLAND WIND FLOW THIS AFTERNOON...AS SYNOPTIC
BACKGROUND WINDS REMAIN LIGHT EAST SOUTHEASTERLY. AFTERNOON LIHUE
AND HILO SOUNDINGS ARE NOT THAT MUCH DIFFERENT...COMPARED TO
YESTERDAYS...EXCEPT FOR THE LOWER LOW LEVEL MOISTURE DEPTH. AIR MASS
REMAINS MARGINALLY UNSTABLE...WITH NEAR NORMAL MOISTURE AS INDICATED
BY THE SOUNDINGS. AS THE EVENING FALLS...EXPECT A SLOW CLEARING OF
SKIES OVER THE ISLANDS...WITH LAND BREEZES DEVELOPING OVERNIGHT.

EVEN THOUGH A SURFACE TROUGH WILL PERSIST FAR NORTHWEST OF THE
ISLANDS THROUGH EARLY PART OF THIS WEEK...FORECAST MODELS CONTINUE
TO INDICATE A SURFACE HIGH PRESSURE RIDGE WILL DEVELOP NORTH OF THE
STATE IN THE COMING DAYS. THIS WILL ALLOW STRONGER TRADES TO RETURN
TO THE ISLANDS. IN FACT...THE ISLANDS ARE EXPECTED TO SEE THESE
TRADE WINDS BEGINNING TUESDAY. AS THIS RIDGE WILL NOT BE TOO
STRONG...THE SURFACE PRESSURE GRADIENT ACROSS THE ISLANDS WILL
REMAIN SOMEWHAT SLACK AND THUS THE BUILDING TRADE WINDS WILL BE
MODEST AT MOST. THEREFORE...MAY SEE A HYBRID TRADE WIND AND
CONVECTIVE WEATHER PATTERN OVER THE ISLANDS THROUGH THIS WEEK...WITH
CLOUDS AND SHOWERS EMBEDDED IN THE TRADE WINDS TO AFFECT WINDWARD
AREAS...WHILE AFTERNOON CLOUDS WITH POSSIBLE A FEW SHOWERS WILL
BUILD OVER THE LEE AREAS. THE MODELS STILL SHOW A DECREASE IN LOW
LEVEL MOISTURE ACROSS THE STATE BY WEDNESDAY. THIS MAY LEAD TO
LIMITED PRECIPITATION FOR THE ISLANDS.

MODEL RUNS ALSO CONTINUE TO SHOW HIGHER LOW LEVEL MOISTURE EMBEDDED
IN THE TRADE WIND FLOW REACHING THE ISLANDS TOWARDS THE WEEKEND.
THIS MOISTURE APPEARS TO BE LOOSELY ASSOCIATED WITH THE REMNANT OF
MARIE. THEREFORE...EXPECT AN UPTICK IN THE SHOWERS UNDER THE LIGHT
TO MODERATE TRADE WINDS FOR THE STATE BY THE WEEKEND.

&&

.AVIATION...
SEABREEZE DEVELOPMENT HAS ALLOWED FOR CLOUD BUILDUPS AND SHOWERS TO
FORM OVER THE ISLANDS. WITH SUNSET...THESE CLOUDS AND SHOWERS WILL
SCATTER OUT AND OVERNIGHT THE ISLANDS SHOULD REMAIN FAIRLY QUIET.
WINDWARD AND MOUNTAIN AREAS MAY EXPERIENCE ISOL MVFR CONDITIONS AS
WEAK TRADE WIND FLOW BEGINS TO COME BACK. THERE ARE NO AIRMETS IN
EFFECT.

&&

.MARINE...
LATEST READINGS FROM NEAR SHORE BUOY JUST SOUTHWEST OF OAHU SHOWED
A SLOW DOWNWARD TREND...AS EXPECTED. LOOK FOR THE ELEVATED SURF FOR
SOUTH FACING SHORES TO SLOWLY SUBSIDE THROUGH REST OF THE DAY INTO
TUESDAY.

A VERY LONG PERIOD SOUTH SWELL...20-25 SECONDS...IS DUE TO ARRIVE
EARLY TUESDAY...THEN BUILDING THROUGH WEDNESDAY. THIS SWELL WILL
LIKELY PRODUCE ADVISORY LEVEL SURF WEDNESDAY INTO THURSDAY.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS
AT LEAST FOR THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

AVIATION...EATON
REST...HUI







000
FXHW60 PHFO 020203
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST MON SEP 1 2014

.SYNOPSIS...
LIGHT WINDS WILL ALLOW LAND BREEZES TO DEVELOP LATER TONIGHT AS THE
LAND COOLS...RESULTING IN CLEARING SKIES OVERNIGHT. SLIGHTLY
STRONGER TRADES ARE EXPECTED TO BUILD IN THE NEXT FEW DAYS AS A HIGH
PRESSURE RIDGE EXTENDS NORTH OF THE ISLANDS. WITH THE STRENGTHENING
TRADES...EXPECT THE CLOUDS AND SHOWERS TO BE FOCUSED MORE OVER THE
WINDWARD SLOPES.

&&

.DISCUSSION...
AFTERNOON CONVECTION BUILT OVER THE ISLAND THIS AFTERNOON AS
EXPECTED...WITH LOCALIZED SHOWERS...RATHER HEAVY OVER WINDWARD OAHU
IN THE PAST HOUR. A FEW GAGES REPORTED ALMOST HALF AN INCH OF RAIN
IN THE PAST FIFTEEN MINUTES. THEREFORE HAVE ISSUED A FLOOD ADVISORY
FOR WINDWARD OAHU AT TIME. EXPECT THE CONVECTION TO PEAK IN THE NEXT
FEW HOURS...THEN SLOWLY DISSIPATES AFTER SUNSET. SEA BREEZES PRETTY
MUCH DOMINATE THE ISLAND WIND FLOW THIS AFTERNOON...AS SYNOPTIC
BACKGROUND WINDS REMAIN LIGHT EAST SOUTHEASTERLY. AFTERNOON LIHUE
AND HILO SOUNDINGS ARE NOT THAT MUCH DIFFERENT...COMPARED TO
YESTERDAYS...EXCEPT FOR THE LOWER LOW LEVEL MOISTURE DEPTH. AIR MASS
REMAINS MARGINALLY UNSTABLE...WITH NEAR NORMAL MOISTURE AS INDICATED
BY THE SOUNDINGS. AS THE EVENING FALLS...EXPECT A SLOW CLEARING OF
SKIES OVER THE ISLANDS...WITH LAND BREEZES DEVELOPING OVERNIGHT.

EVEN THOUGH A SURFACE TROUGH WILL PERSIST FAR NORTHWEST OF THE
ISLANDS THROUGH EARLY PART OF THIS WEEK...FORECAST MODELS CONTINUE
TO INDICATE A SURFACE HIGH PRESSURE RIDGE WILL DEVELOP NORTH OF THE
STATE IN THE COMING DAYS. THIS WILL ALLOW STRONGER TRADES TO RETURN
TO THE ISLANDS. IN FACT...THE ISLANDS ARE EXPECTED TO SEE THESE
TRADE WINDS BEGINNING TUESDAY. AS THIS RIDGE WILL NOT BE TOO
STRONG...THE SURFACE PRESSURE GRADIENT ACROSS THE ISLANDS WILL
REMAIN SOMEWHAT SLACK AND THUS THE BUILDING TRADE WINDS WILL BE
MODEST AT MOST. THEREFORE...MAY SEE A HYBRID TRADE WIND AND
CONVECTIVE WEATHER PATTERN OVER THE ISLANDS THROUGH THIS WEEK...WITH
CLOUDS AND SHOWERS EMBEDDED IN THE TRADE WINDS TO AFFECT WINDWARD
AREAS...WHILE AFTERNOON CLOUDS WITH POSSIBLE A FEW SHOWERS WILL
BUILD OVER THE LEE AREAS. THE MODELS STILL SHOW A DECREASE IN LOW
LEVEL MOISTURE ACROSS THE STATE BY WEDNESDAY. THIS MAY LEAD TO
LIMITED PRECIPITATION FOR THE ISLANDS.

MODEL RUNS ALSO CONTINUE TO SHOW HIGHER LOW LEVEL MOISTURE EMBEDDED
IN THE TRADE WIND FLOW REACHING THE ISLANDS TOWARDS THE WEEKEND.
THIS MOISTURE APPEARS TO BE LOOSELY ASSOCIATED WITH THE REMNANT OF
MARIE. THEREFORE...EXPECT AN UPTICK IN THE SHOWERS UNDER THE LIGHT
TO MODERATE TRADE WINDS FOR THE STATE BY THE WEEKEND.

&&

.AVIATION...
SEABREEZE DEVELOPMENT HAS ALLOWED FOR CLOUD BUILDUPS AND SHOWERS TO
FORM OVER THE ISLANDS. WITH SUNSET...THESE CLOUDS AND SHOWERS WILL
SCATTER OUT AND OVERNIGHT THE ISLANDS SHOULD REMAIN FAIRLY QUIET.
WINDWARD AND MOUNTAIN AREAS MAY EXPERIENCE ISOL MVFR CONDITIONS AS
WEAK TRADE WIND FLOW BEGINS TO COME BACK. THERE ARE NO AIRMETS IN
EFFECT.

&&

.MARINE...
LATEST READINGS FROM NEAR SHORE BUOY JUST SOUTHWEST OF OAHU SHOWED
A SLOW DOWNWARD TREND...AS EXPECTED. LOOK FOR THE ELEVATED SURF FOR
SOUTH FACING SHORES TO SLOWLY SUBSIDE THROUGH REST OF THE DAY INTO
TUESDAY.

A VERY LONG PERIOD SOUTH SWELL...20-25 SECONDS...IS DUE TO ARRIVE
EARLY TUESDAY...THEN BUILDING THROUGH WEDNESDAY. THIS SWELL WILL
LIKELY PRODUCE ADVISORY LEVEL SURF WEDNESDAY INTO THURSDAY.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS
AT LEAST FOR THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

AVIATION...EATON
REST...HUI






000
FXHW60 PHFO 011950
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST MON SEP 1 2014

.SYNOPSIS...
A LIGHT EAST-SOUTHEAST WIND FLOW IS EXPECTED TO CONTINUE TODAY AS A
SURFACE TROUGH STAYS FAR NORTHWEST OF THE STATE. THE LIGHT WINDS
WILL ALLOW AFTERNOON SEA BREEZES TO DEVELOP...BRINGING LOCALIZED
CLOUD BUILDUPS WITH POSSIBLY A FEW SHOWERS MAINLY OVER LEEWARD AND
INTERIOR AREAS. SLIGHTLY STRONGER TRADES ARE EXPECTED TO BUILD IN
LATER THIS WEEK AS A HIGH PRESSURE RIDGE BUILDS NORTH OF THE
ISLANDS. WITH THE STRENGTHENING TRADES...EXPECT THE CLOUDS AND
SHOWERS TO BE FOCUSED MORE OVER THE WINDWARD SLOPES.

&&

.DISCUSSION...
ONCE AGAIN...RATHER FAIR WEATHER PREVAILS OVER THE STATE THIS
MORNING AS LIGHT WINDS PERSIST WITH LAND BREEZES OVER THE ISLANDS. A
SURFACE TROUGH FAR NORTHWEST OF THE STATE IS KEEPING SYNOPTIC WIND
FLOW EAST SOUTHEASTERLY AND LIGHT ACROSS THE ISLANDS TODAY. AS THE
DAY PROGRESSES...SEA BREEZES WILL DEVELOP...RESULTING IN LOCALIZED
CLOUDS FORMING OVER THE LEE AND INTERIOR SECTIONS OF THE ISLANDS.
AIR MASS IS MARGINALLY UNSTABLE...WITH NEAR NORMAL MOISTURE AS
INDICATED BY EARLY MORNING SOUNDINGS. THEREFORE...DAYTIME CLOUDS MAY
BRING SOME SHOWERS TO THE AFOREMENTIONED AREAS.

ALTHOUGH THAT SURFACE TROUGH WILL PERSIST FAR NORTHWEST OF THE
ISLANDS THROUGH EARLY THIS WEEK...FORECAST MODELS CONTINUE TO
INDICATE A SURFACE HIGH PRESSURE RIDGE WILL DEVELOP NORTH OF THE
STATE IN THE COMING DAYS. THIS WILL ALLOW STRONGER TRADES TO RETURN
TO THE ISLANDS. AS THIS RIDGE WILL NOT BE TOO STRONG...THE SURFACE
PRESSURE GRADIENT ACROSS THE ISLANDS WILL REMAIN SOMEWHAT SLACK AND
THUS THE BUILDING TRADE WINDS WILL BE MODEST AT MOST.
THEREFORE...MAY SEE A MORE HYBRID TRADE WIND AND CONVECTIVE WEATHER
PATTERN IN THE NEXT FEW DAYS WITH CLOUDS AND SHOWERS EMBEDDED IN THE
TRADE WINDS TO AFFECT WINDWARD AREAS...WHILE AFTERNOON CLOUDS WITH
POSSIBLE A FEW SHOWERS WILL BUILD OVER THE LEE AREAS. THE MODELS
ALSO SHOW LIMITED LOW LEVEL MOISTURE IN THE NEXT COUPLE OF DAYS
ACROSS THE STATE...AND THIS MAY RESULT LIMITED PRECIPITATION FOR THE
ISLANDS AS WELL.

MODEL RUNS CONTINUE TO SHOW HIGHER LOW LEVEL MOISTURE EMBEDDED
IN THE TRADE WIND FLOW REACHING THE ISLANDS TOWARDS THE LATER PART
OF THE WEEK. THIS INCREASED MOISTURE APPEARS TO BE LOOSELY
ASSOCIATED WITH THE REMNANT OF MARIE. THEREFORE...EXPECT AN
UPTICK IN THE SHOWERS UNDER THE LIGHT TO MODERATE TRADE WINDS FOR
THE STATE.

&&

.AVIATION...
LIGHT ESE BACKGROUND FLOW WILL CONTINUE TODAY. SEABREEZES SHOULD
DEVELOP THIS AFTERNOON...BRINGING CLOUDS AND POSSIBLE SHOWERS TO THE
INTERIOR AND LEEWARD AREAS. BRIEF PERIODS OF MVFR MAY OCCUR WITHIN
THESE CLOUDS AND SHOWERS. ANY SEABREEZE INDUCED CONVECTION WILL
DIMINISH WITH SUNSET. ISOLATED MVFR WILL ALSO BE POSSIBLE ACROSS
WINDWARD SECTIONS TONIGHT AS WEAK TRADE WIND FLOW RESUMES.
OTHERWISE...VFR WILL PREVAIL THROUGH THE PERIOD.

&&

.MARINE...
THE CURRENT SOUTH SWELL CONTINUES THIS MORNING...WITH READINGS FROM
NEAR SHORE BUOY JUST SOUTHWEST OF OAHU REMAINED ELEVATED. EXPECT THE
ELEVATED SURF TO PERSIST TODAY...THEN SLOWLY SUBSIDE TONIGHT.

A VERY LONG PERIOD SOUTH SWELL...20-25 SECONDS...IS DUE TO ARRIVE
EARLY TUESDAY...THEN BUILDING THROUGH WEDNESDAY. THIS SWELL WILL
LIKELY PRODUCE ADVISORY LEVEL SURF WEDNESDAY INTO THURSDAY.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

AVIATION...EATON
REST...HUI







000
FXHW60 PHFO 011950
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST MON SEP 1 2014

.SYNOPSIS...
A LIGHT EAST-SOUTHEAST WIND FLOW IS EXPECTED TO CONTINUE TODAY AS A
SURFACE TROUGH STAYS FAR NORTHWEST OF THE STATE. THE LIGHT WINDS
WILL ALLOW AFTERNOON SEA BREEZES TO DEVELOP...BRINGING LOCALIZED
CLOUD BUILDUPS WITH POSSIBLY A FEW SHOWERS MAINLY OVER LEEWARD AND
INTERIOR AREAS. SLIGHTLY STRONGER TRADES ARE EXPECTED TO BUILD IN
LATER THIS WEEK AS A HIGH PRESSURE RIDGE BUILDS NORTH OF THE
ISLANDS. WITH THE STRENGTHENING TRADES...EXPECT THE CLOUDS AND
SHOWERS TO BE FOCUSED MORE OVER THE WINDWARD SLOPES.

&&

.DISCUSSION...
ONCE AGAIN...RATHER FAIR WEATHER PREVAILS OVER THE STATE THIS
MORNING AS LIGHT WINDS PERSIST WITH LAND BREEZES OVER THE ISLANDS. A
SURFACE TROUGH FAR NORTHWEST OF THE STATE IS KEEPING SYNOPTIC WIND
FLOW EAST SOUTHEASTERLY AND LIGHT ACROSS THE ISLANDS TODAY. AS THE
DAY PROGRESSES...SEA BREEZES WILL DEVELOP...RESULTING IN LOCALIZED
CLOUDS FORMING OVER THE LEE AND INTERIOR SECTIONS OF THE ISLANDS.
AIR MASS IS MARGINALLY UNSTABLE...WITH NEAR NORMAL MOISTURE AS
INDICATED BY EARLY MORNING SOUNDINGS. THEREFORE...DAYTIME CLOUDS MAY
BRING SOME SHOWERS TO THE AFOREMENTIONED AREAS.

ALTHOUGH THAT SURFACE TROUGH WILL PERSIST FAR NORTHWEST OF THE
ISLANDS THROUGH EARLY THIS WEEK...FORECAST MODELS CONTINUE TO
INDICATE A SURFACE HIGH PRESSURE RIDGE WILL DEVELOP NORTH OF THE
STATE IN THE COMING DAYS. THIS WILL ALLOW STRONGER TRADES TO RETURN
TO THE ISLANDS. AS THIS RIDGE WILL NOT BE TOO STRONG...THE SURFACE
PRESSURE GRADIENT ACROSS THE ISLANDS WILL REMAIN SOMEWHAT SLACK AND
THUS THE BUILDING TRADE WINDS WILL BE MODEST AT MOST.
THEREFORE...MAY SEE A MORE HYBRID TRADE WIND AND CONVECTIVE WEATHER
PATTERN IN THE NEXT FEW DAYS WITH CLOUDS AND SHOWERS EMBEDDED IN THE
TRADE WINDS TO AFFECT WINDWARD AREAS...WHILE AFTERNOON CLOUDS WITH
POSSIBLE A FEW SHOWERS WILL BUILD OVER THE LEE AREAS. THE MODELS
ALSO SHOW LIMITED LOW LEVEL MOISTURE IN THE NEXT COUPLE OF DAYS
ACROSS THE STATE...AND THIS MAY RESULT LIMITED PRECIPITATION FOR THE
ISLANDS AS WELL.

MODEL RUNS CONTINUE TO SHOW HIGHER LOW LEVEL MOISTURE EMBEDDED
IN THE TRADE WIND FLOW REACHING THE ISLANDS TOWARDS THE LATER PART
OF THE WEEK. THIS INCREASED MOISTURE APPEARS TO BE LOOSELY
ASSOCIATED WITH THE REMNANT OF MARIE. THEREFORE...EXPECT AN
UPTICK IN THE SHOWERS UNDER THE LIGHT TO MODERATE TRADE WINDS FOR
THE STATE.

&&

.AVIATION...
LIGHT ESE BACKGROUND FLOW WILL CONTINUE TODAY. SEABREEZES SHOULD
DEVELOP THIS AFTERNOON...BRINGING CLOUDS AND POSSIBLE SHOWERS TO THE
INTERIOR AND LEEWARD AREAS. BRIEF PERIODS OF MVFR MAY OCCUR WITHIN
THESE CLOUDS AND SHOWERS. ANY SEABREEZE INDUCED CONVECTION WILL
DIMINISH WITH SUNSET. ISOLATED MVFR WILL ALSO BE POSSIBLE ACROSS
WINDWARD SECTIONS TONIGHT AS WEAK TRADE WIND FLOW RESUMES.
OTHERWISE...VFR WILL PREVAIL THROUGH THE PERIOD.

&&

.MARINE...
THE CURRENT SOUTH SWELL CONTINUES THIS MORNING...WITH READINGS FROM
NEAR SHORE BUOY JUST SOUTHWEST OF OAHU REMAINED ELEVATED. EXPECT THE
ELEVATED SURF TO PERSIST TODAY...THEN SLOWLY SUBSIDE TONIGHT.

A VERY LONG PERIOD SOUTH SWELL...20-25 SECONDS...IS DUE TO ARRIVE
EARLY TUESDAY...THEN BUILDING THROUGH WEDNESDAY. THIS SWELL WILL
LIKELY PRODUCE ADVISORY LEVEL SURF WEDNESDAY INTO THURSDAY.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

AVIATION...EATON
REST...HUI






000
FXHW60 PHFO 011330
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST MON SEP 1 2014

.SYNOPSIS...
A LIGHT EAST-SOUTHEAST FLOW IS EXPECTED TO CONTINUE TODAY WITH HIGH
PRESSURE REMAINS FAR NORTHEAST ...AND A SURFACE TROUGH NEAR THE
ISLANDS. HEADING TOWARDS MIDWEEK...LIGHT TO MODERATE TRADES ARE
EXPECTED TO BUILD IN. THE LIGHT WINDS WILL ALLOW AFTERNOON SEA
BREEZES TO BRING LOCALIZED CLOUD BUILDUPS AND A FEW SHOWERS OVER
LEEWARD AND INTERIOR AREAS. AS THE WEEK PROGRESSES AND THE TRADES
STRENGTHEN...EXPECT THE LIMITED CLOUDS AND SHOWERS TO BE FOCUSED
OVER THE WINDWARD SLOPES. TRADE WIND SHOWERS MAY INCREASE BY FRIDAY
AS LOW LEVEL MOISTURE RIDES IN ON THE TRADES.

&&

.DISCUSSION...
THE OVERNIGHT SOUNDING AT HILO SHOWED A LOW LEVEL INVERSION WITHIN
400 FT OF THE SURFACE. THIS IS SIMILAR TO AN INVERSION OBSERVED
YESTERDAY MORNING...BUT THIS MORNING/S IS NOT QUITE AS STRONG AS
YESTERDAY/S. THE STRONG LOW LEVEL INVERSION YESTERDAY MORNING
ALLOWED SMOKE AND ODORS ASSOCIATED WITH THE RELATIVELY NEW LAVA FLOW
IN THE PUNA DISTRICT TO BECOME TRAPPED NEAR THE SURFACE UNTIL MID
MORNING WHEN THE HEAT OF THE DAY HELPED TO DISSIPATE THE INVERSION.
WITH THE MORNING SOUNDING SHOWING THE INVERSION AGAIN...EVEN THOUGH
NOT QUITE AS STRONG...IT/S VERY LIKELY SIMILAR EVENTS WILL BE
OBSERVED THIS MORNING...THUS THE MENTION OF SMOKE IN THE GRIDS. THE
WEAKER INVERSION TODAY MAY MEAN IT WILL BREAK UP A LITTLE SOONER
THAN YESTERDAY.

NO MAJOR CHANGES TO THE FORECAST FOR THIS MORNING. THE CLOUDS OVER
THE BIG ISLAND LAST EVENING BEGAN TO BREAK UP OVER THE NORTHWEST
HALF OF THE ISLAND SHORTLY AFTER MIDNIGHT...LEAVING CLOUDS AND SOME
SHOWERS OVER THE SLOPES FROM HILO TO CAPE KUMUKAHI TO SOUTH POINT.
THIS BATCH OF CLOUDS IS ASSOCIATED WITH A WEAK SURFACE TROUGH DRAPED
ACROSS THE ISLANDS OF MAUI COUNTY AND THE BIG ISLAND. THESE CLOUDS
ARE MOVING TO THE WEST NORTHWEST...WITH THE BULK OF THE CLOUDS
EXPECTED TO PASS SOUTH OF THE SMALLER ISLANDS TODAY. THE PRESENCE OF
THIS TROUGH IS DISRUPTING THE TRADE WIND FLOW GENERATED BY THE HIGH
PRESSURE SYSTEM FAR NORTHEAST OF THE ISLANDS.

THE MODELS ARE IN GOOD AGREEMENT WITH THE HIGH LINGERING TO THE FAR
NORTHEAST OF THE ISLANDS THROUGH MUCH OF THE WEEK. THE SURFACE
TROUGH NEAR THE ISLANDS SHOULD START TO DISSIPATE AND MOVE AWAY FROM
THE ISLANDS HEADING INTO MID WEEK...WHICH WILL ALLOW THE TRADES TO
MAKE A RETURN APPEARANCE. HOWEVER...A LOW NORTHEAST OF THE
ISLANDS...AND A FRONT PASSING NORTHWEST OF THE ISLANDS WILL HELP
PREVENT MORE THAN LIGHT TO MODERATE TRADES TO BUILD BACK IN. AS THE
WINDS INCREASE...LOOK FOR CLOUDS AND SHOWERS TO BECOME FOCUSED MORE
OVER THE WINDWARD SLOPES. THE GFS AND ECMWF BOTH SHOW LIMITED LOW
LEVEL MOISTURE DURING THE MIDDLE OF THE WEEK...SO EXPECT SHOWER
ACTIVITY TO BE ON THE LIGHT SIDE.

BOTH MODELS DO SHOW ADDITIONAL LOW LEVEL MOISTURE BEING CARRIED IN
ON THE TRADES AT THE END OF THE WEEK. THIS INCREASED MOISTURE
APPEARS TO BE LOOSELY ASSOCIATED WITH THE REMNANT OF MARIE THAT IS
PASSING FAR NORTHEAST OF THE ISLANDS. AS SUCH...LOOK FOR MORE
SHOWERS AT THE END OF THE WEEK THAN AT MIDWEEK.

&&

.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS THE STATE TODAY AND TONIGHT.
CLOUDS AND WIDELY SCATTERED SHOWERS SHOULD DEVELOP ONCE AGAIN THIS
AFTERNOON ALONG SEABREEZES ACROSS INTERIOR AND LEEWARD AREAS...WITH
ISOLATED MVFR CONDITIONS POSSIBLE. ISOLATED MVFR WILL ALSO BE
POSSIBLE ACROSS WINDWARD SECTIONS TONIGHT AS WEAK TRADE WIND FLOW
RESUMES.

&&

.MARINE...
THE NEAR SHORE BUOYS CONTINUED TO SHOW STEADY READINGS OVERNIGHT.
THE REINFORCEMENT TO THE CURRENT SOUTH SWELL STARTED TO MAKE AN
APPEARANCE ON THE 51003 BUOY OVERNIGHT WITH PERIODIC 15 SECOND
ENERGY BEING PICKED UP. SURF ALONG THE SOUTH FACING SHORES IS
EXPECTED TO REMAIN ELEVATED...BUT BELOW ADVISORY LEVELS INTO
TUESDAY.

A VERY LONG PERIOD SOUTH SWELL...20-25 SECONDS...IS DUE TO
ARRIVE TUESDAY...AND BUILD THROUGH WEDNESDAY. THIS SWELL WILL LIKELY
PRODUCE ADVISORY LEVEL SURF INTO THURSDAY.

THE LONG PERIOD SWELL FROM THE EAST SHOULD CONTINUE TO TREND DOWN
TODAY. WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
THRESHOLDS FOR AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...M BALLARD
AVIATION...JACOBSON







000
FXHW60 PHFO 011330
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST MON SEP 1 2014

.SYNOPSIS...
A LIGHT EAST-SOUTHEAST FLOW IS EXPECTED TO CONTINUE TODAY WITH HIGH
PRESSURE REMAINS FAR NORTHEAST ...AND A SURFACE TROUGH NEAR THE
ISLANDS. HEADING TOWARDS MIDWEEK...LIGHT TO MODERATE TRADES ARE
EXPECTED TO BUILD IN. THE LIGHT WINDS WILL ALLOW AFTERNOON SEA
BREEZES TO BRING LOCALIZED CLOUD BUILDUPS AND A FEW SHOWERS OVER
LEEWARD AND INTERIOR AREAS. AS THE WEEK PROGRESSES AND THE TRADES
STRENGTHEN...EXPECT THE LIMITED CLOUDS AND SHOWERS TO BE FOCUSED
OVER THE WINDWARD SLOPES. TRADE WIND SHOWERS MAY INCREASE BY FRIDAY
AS LOW LEVEL MOISTURE RIDES IN ON THE TRADES.

&&

.DISCUSSION...
THE OVERNIGHT SOUNDING AT HILO SHOWED A LOW LEVEL INVERSION WITHIN
400 FT OF THE SURFACE. THIS IS SIMILAR TO AN INVERSION OBSERVED
YESTERDAY MORNING...BUT THIS MORNING/S IS NOT QUITE AS STRONG AS
YESTERDAY/S. THE STRONG LOW LEVEL INVERSION YESTERDAY MORNING
ALLOWED SMOKE AND ODORS ASSOCIATED WITH THE RELATIVELY NEW LAVA FLOW
IN THE PUNA DISTRICT TO BECOME TRAPPED NEAR THE SURFACE UNTIL MID
MORNING WHEN THE HEAT OF THE DAY HELPED TO DISSIPATE THE INVERSION.
WITH THE MORNING SOUNDING SHOWING THE INVERSION AGAIN...EVEN THOUGH
NOT QUITE AS STRONG...IT/S VERY LIKELY SIMILAR EVENTS WILL BE
OBSERVED THIS MORNING...THUS THE MENTION OF SMOKE IN THE GRIDS. THE
WEAKER INVERSION TODAY MAY MEAN IT WILL BREAK UP A LITTLE SOONER
THAN YESTERDAY.

NO MAJOR CHANGES TO THE FORECAST FOR THIS MORNING. THE CLOUDS OVER
THE BIG ISLAND LAST EVENING BEGAN TO BREAK UP OVER THE NORTHWEST
HALF OF THE ISLAND SHORTLY AFTER MIDNIGHT...LEAVING CLOUDS AND SOME
SHOWERS OVER THE SLOPES FROM HILO TO CAPE KUMUKAHI TO SOUTH POINT.
THIS BATCH OF CLOUDS IS ASSOCIATED WITH A WEAK SURFACE TROUGH DRAPED
ACROSS THE ISLANDS OF MAUI COUNTY AND THE BIG ISLAND. THESE CLOUDS
ARE MOVING TO THE WEST NORTHWEST...WITH THE BULK OF THE CLOUDS
EXPECTED TO PASS SOUTH OF THE SMALLER ISLANDS TODAY. THE PRESENCE OF
THIS TROUGH IS DISRUPTING THE TRADE WIND FLOW GENERATED BY THE HIGH
PRESSURE SYSTEM FAR NORTHEAST OF THE ISLANDS.

THE MODELS ARE IN GOOD AGREEMENT WITH THE HIGH LINGERING TO THE FAR
NORTHEAST OF THE ISLANDS THROUGH MUCH OF THE WEEK. THE SURFACE
TROUGH NEAR THE ISLANDS SHOULD START TO DISSIPATE AND MOVE AWAY FROM
THE ISLANDS HEADING INTO MID WEEK...WHICH WILL ALLOW THE TRADES TO
MAKE A RETURN APPEARANCE. HOWEVER...A LOW NORTHEAST OF THE
ISLANDS...AND A FRONT PASSING NORTHWEST OF THE ISLANDS WILL HELP
PREVENT MORE THAN LIGHT TO MODERATE TRADES TO BUILD BACK IN. AS THE
WINDS INCREASE...LOOK FOR CLOUDS AND SHOWERS TO BECOME FOCUSED MORE
OVER THE WINDWARD SLOPES. THE GFS AND ECMWF BOTH SHOW LIMITED LOW
LEVEL MOISTURE DURING THE MIDDLE OF THE WEEK...SO EXPECT SHOWER
ACTIVITY TO BE ON THE LIGHT SIDE.

BOTH MODELS DO SHOW ADDITIONAL LOW LEVEL MOISTURE BEING CARRIED IN
ON THE TRADES AT THE END OF THE WEEK. THIS INCREASED MOISTURE
APPEARS TO BE LOOSELY ASSOCIATED WITH THE REMNANT OF MARIE THAT IS
PASSING FAR NORTHEAST OF THE ISLANDS. AS SUCH...LOOK FOR MORE
SHOWERS AT THE END OF THE WEEK THAN AT MIDWEEK.

&&

.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS THE STATE TODAY AND TONIGHT.
CLOUDS AND WIDELY SCATTERED SHOWERS SHOULD DEVELOP ONCE AGAIN THIS
AFTERNOON ALONG SEABREEZES ACROSS INTERIOR AND LEEWARD AREAS...WITH
ISOLATED MVFR CONDITIONS POSSIBLE. ISOLATED MVFR WILL ALSO BE
POSSIBLE ACROSS WINDWARD SECTIONS TONIGHT AS WEAK TRADE WIND FLOW
RESUMES.

&&

.MARINE...
THE NEAR SHORE BUOYS CONTINUED TO SHOW STEADY READINGS OVERNIGHT.
THE REINFORCEMENT TO THE CURRENT SOUTH SWELL STARTED TO MAKE AN
APPEARANCE ON THE 51003 BUOY OVERNIGHT WITH PERIODIC 15 SECOND
ENERGY BEING PICKED UP. SURF ALONG THE SOUTH FACING SHORES IS
EXPECTED TO REMAIN ELEVATED...BUT BELOW ADVISORY LEVELS INTO
TUESDAY.

A VERY LONG PERIOD SOUTH SWELL...20-25 SECONDS...IS DUE TO
ARRIVE TUESDAY...AND BUILD THROUGH WEDNESDAY. THIS SWELL WILL LIKELY
PRODUCE ADVISORY LEVEL SURF INTO THURSDAY.

THE LONG PERIOD SWELL FROM THE EAST SHOULD CONTINUE TO TREND DOWN
TODAY. WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
THRESHOLDS FOR AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...M BALLARD
AVIATION...JACOBSON








000
FXHW60 PHFO 010628
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST SUN AUG 31 2014

.SYNOPSIS...
HIGH PRESSURE FAR NORTH OF THE ISLANDS WILL MOVE TO THE EAST
THROUGH MIDWEEK. SURFACE TROUGHS NEAR AND UPSTREAM OF THE ISLANDS
WILL HELP TO DISRUPT THE TRADE WIND FLOW THROUGH LABOR DAY. EXPECT
LIGHT EAST-SOUTHEAST WINDS TO PREVAIL THROUGH LABOR DAY...FOLLOWED
BY LIGHT TO MODERATE TRADE WINDS FOR THE REMAINDER OF THE WEEK. THE
LIGHT WINDS WILL ALLOW AFTERNOON SEA BREEZES TO PRODUCE LOCALIZED
CLOUD BUILDUPS AND A FEW SHOWERS OVER LEEWARD AND INTERIOR AREAS. AS
TRADE WINDS STRENGTHEN SLIGHTLY TOWARDS THE MIDDLE OF THE WEEK...THE
FOCUS FOR LIMITED CLOUDS AND SHOWERS WILL SHIFT TO WINDWARD SLOPES
AND COASTS. TRADE SHOWERS MAY INCREASE BY FRIDAY AS UPSTREAM
MOISTURE INCREASES.

&&

.DISCUSSION...
GENERAL FORECAST PHILOSOPHY REMAINS THE SAME THIS EVENING...WITH NO
ANTICIPATED UPDATES EXPECTED TO THE FORECAST IN THE SHORT TERM.

PREVIOUS DISCUSSION FOLLOWS.

&&

.PREV DISCUSSION...
ISSUED AT 345 PM

LATEST SATELLITE AND RADAR ANIMATIONS SHOW THE LOW-LEVEL FLOW NEAR
THE ISLANDS IS FROM THE ESE...EFFECTIVELY PLACING THE SMALLER
ISLANDS IN THE WIND SHADOW OF THE BIG ISLAND. A RELATIVELY WEAK 1026
MB SURFACE HIGH CENTERED ABOUT 1500 MILES NNE OF THE ISLANDS IS
DRIVING LIGHT TO MODERATE TRADE WINDS OVER THE TROPICAL CENTRAL N
PACIFIC...BUT WEAK LOW LEVEL TROUGHS NEAR THE ISLANDS HAVE WEAKENED
AND VEERED THE LOW LEVEL FLOW. WITH THE LIGHT WINDS...DAYTIME
HEATING OF THE ISLANDS LED TO SEA BREEZES WHICH DROVE CLOUD AND
SHOWER FORMATION OVER THE ISLANDS. ENHANCED MOISTURE NEAR THE BIG
ISLAND IS ASSOCIATED WITH ONE OF THESE PASSING TROUGHS...WHICH ADDED
SOME FUEL TO THE AFTERNOON CONVECTIVE CLOUDS/SHOWERS THERE. WATER
VAPOR IMAGERY SHOWS RIDGING ALOFT CENTERED OVER THE ISLANDS...WITH
VERY DRY UPPER LEVELS...YET BALLOON SOUNDINGS CONTINUE TO SHOW AN
ELEVATED INVERSION BASE NEAR 10 KFT...AND ABUNDANT MOISTURE BELOW
THIS CAP.

OVERNIGHT...SEA BREEZE-DRIVEN CLOUDS AND SHOWERS WILL PERSIST INTO
THE EARLY EVENING BEFORE DISSIPATING SHORTLY THEREAFTER. WITH THE
LOW LEVEL FLOW CONTINUING TO FAVOR AN ESE DIRECTION...A FEW SHOWERS
WILL MOVE ASHORE OVER E AND SE SHORES AND SLOPES...BUT A MOSTLY DRY
NIGHT IS EXPECTED AS THE BULK OF THE MOISTURE NEAR THE BIG ISLAND
MOVES ON A TRAJECTORY TO KEEP IT AWAY FROM THE OTHER ISLANDS. LIGHT
WINDS ALLOWED A GROUND-BASED INVERSION TO DEVELOP IN MANY AREAS LAST
NIGHT...WHICH IS USUALLY NOT TOO MUCH OF AN ISSUE...BUT SMOKE/ODORS
ASSOCIATED WITH A RELATIVELY NEW LAVA FLOW IN THE PUNA REGION BECAME
TRAPPED NEAR THE SURFACE BEFORE THE INVERSION BROKE BY MID-MORNING
TODAY. THE EXPECTATION IS THAT THIS WILL OCCUR AGAIN TONIGHT...BUT
TRADE WINDS SHOULD BE STRONG ENOUGH BY TUESDAY TO PREVENT THIS FROM
OCCURRING THEREAFTER.

A RELATIVELY DRY WEATHER PATTERN IS EXPECTED OVER THE NEXT COUPLE OF
DAYS. WINDS WILL SLOWLY BACK TO A MORE TYPICAL TRADE WIND
DIRECTION...AND STRENGTHEN SLIGHTLY...ON MONDAY AND TUESDAY AS THE
TROUGHS NEAR THE ISLANDS WEAKEN FURTHER AND MOVE NW...AND THE
SURFACE RIDGE TO THE N REBOUNDS SOMEWHAT. UNTIL THE TRADES FIRM
UP...WEATHER OVER LEEWARD AREAS WILL BE DRIVEN BY LAND AND SEA
BREEZES...WITH A MOSTLY CLEAR OVERNIGHT/MORNING...AND INCREASING
LATE MORNING CLOUDS LEADING TO A FEW AFTERNOON SHOWERS THAT
GRADUALLY CLEAR IN THE EVENING.

AS TRADE WINDS STRENGTHEN SOMEWHAT TUESDAY AND REMAIN LIGHT TO
MODERATE THROUGH THE WEEK...LEEWARD AREAS WILL BE MOSTLY DRY...WITH
BRIEF SHOWERS OVER WINDWARD AREAS. THE EXCEPTION IS LEEWARD BIG
ISLAND...WHERE CLOUDS AND A FEW SHOWERS WILL FAVOR AFTERNOON AND
EVENING HOURS BEFORE CLEARING LATE AT NIGHT. MID-LEVEL RIDGING
PERSISTING IN THE AREA WILL KEEP THE ISLAND ATMOSPHERE STABLE...AND
NO SIGNIFICANT MOISTURE SOURCES ARE EXPECTED THROUGH THURSDAY...THUS
RAINFALL TOTALS WILL BE ON THE LOW END. INCREASED MOISTURE LOOSELY
ASSOCIATED WITH THE REMNANT OF MARIE PASSING FAR NE OF THE ISLANDS
MAY INCREASE WINDWARD SHOWERS FROM THURSDAY NIGHT THROUGH SATURDAY...
WITH THIS SOLUTION SHARED BY BOTH THE GFS AND ECMWF.

&&

.AVIATION...
PERIODS OF MVFR CONDITIONS WILL IMPACT PHTO TERMINAL OVERNIGHT AS
SHOWERS AND CLOUDS MOVE INTO THE BIG ISLAND FROM THE SOUTHEAST...AND
AN AIRMET FOR MOUNTAIN OBSCURATION MAY BE NEEDED FROM HILO SOUTHWARD
ALONG THE PUNA AND KAU COASTS.

VFR CONDITIONS WILL PREVAIL ELSEWHERE TONIGHT AND MONDAY. CLOUDS AND
WIDELY SCATTERED SHOWERS SHOULD DEVELOP ONCE AGAIN MONDAY AFTERNOON
ALONG SEABREEZES ACROSS INTERIOR AND LEEWARD AREAS...WITH ISOLATED
MVFR CONDITIONS POSSIBLE.

&&

.MARINE...
ISSUED AT 345 PM

A MODEST REINFORCEMENT TO THE CURRENT S SWELL IS EXPECTED INTO
MONDAY...BUT IS NOT READILY APPARENT IN LATEST BUOY/SURF
OBSERVATIONS...WITH MOST OBSERVATIONS SHOWING LITTLE CHANGE OVER
THE PAST 24 HOURS OR SO. SURF ALONG S FACING SHORES IS EXPECTED TO
REMAIN BELOW ADVISORY LEVELS INTO TUESDAY...BUT A VERY LONG PERIOD
/20-25 SECOND/ S SWELL ARRIVING TUESDAY AND BUILDING THROUGH
WEDNESDAY WILL LIKELY PRODUCE ADVISORY LEVEL SURF ALONG S FACING
SHORES INTO THURSDAY. LONG PERIOD SWELL FROM THE E CONTINUES TO BE
OBSERVED...BUT SHOULD CONTINUE TO TREND DOWN THROUGH MONDAY. WINDS
AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR AT
LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION...M BALLARD
PREV DISCUSSION/MARINE...BIRCHARD
AVIATION...JACOBSON







000
FXHW60 PHFO 010628
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST SUN AUG 31 2014

.SYNOPSIS...
HIGH PRESSURE FAR NORTH OF THE ISLANDS WILL MOVE TO THE EAST
THROUGH MIDWEEK. SURFACE TROUGHS NEAR AND UPSTREAM OF THE ISLANDS
WILL HELP TO DISRUPT THE TRADE WIND FLOW THROUGH LABOR DAY. EXPECT
LIGHT EAST-SOUTHEAST WINDS TO PREVAIL THROUGH LABOR DAY...FOLLOWED
BY LIGHT TO MODERATE TRADE WINDS FOR THE REMAINDER OF THE WEEK. THE
LIGHT WINDS WILL ALLOW AFTERNOON SEA BREEZES TO PRODUCE LOCALIZED
CLOUD BUILDUPS AND A FEW SHOWERS OVER LEEWARD AND INTERIOR AREAS. AS
TRADE WINDS STRENGTHEN SLIGHTLY TOWARDS THE MIDDLE OF THE WEEK...THE
FOCUS FOR LIMITED CLOUDS AND SHOWERS WILL SHIFT TO WINDWARD SLOPES
AND COASTS. TRADE SHOWERS MAY INCREASE BY FRIDAY AS UPSTREAM
MOISTURE INCREASES.

&&

.DISCUSSION...
GENERAL FORECAST PHILOSOPHY REMAINS THE SAME THIS EVENING...WITH NO
ANTICIPATED UPDATES EXPECTED TO THE FORECAST IN THE SHORT TERM.

PREVIOUS DISCUSSION FOLLOWS.

&&

.PREV DISCUSSION...
ISSUED AT 345 PM

LATEST SATELLITE AND RADAR ANIMATIONS SHOW THE LOW-LEVEL FLOW NEAR
THE ISLANDS IS FROM THE ESE...EFFECTIVELY PLACING THE SMALLER
ISLANDS IN THE WIND SHADOW OF THE BIG ISLAND. A RELATIVELY WEAK 1026
MB SURFACE HIGH CENTERED ABOUT 1500 MILES NNE OF THE ISLANDS IS
DRIVING LIGHT TO MODERATE TRADE WINDS OVER THE TROPICAL CENTRAL N
PACIFIC...BUT WEAK LOW LEVEL TROUGHS NEAR THE ISLANDS HAVE WEAKENED
AND VEERED THE LOW LEVEL FLOW. WITH THE LIGHT WINDS...DAYTIME
HEATING OF THE ISLANDS LED TO SEA BREEZES WHICH DROVE CLOUD AND
SHOWER FORMATION OVER THE ISLANDS. ENHANCED MOISTURE NEAR THE BIG
ISLAND IS ASSOCIATED WITH ONE OF THESE PASSING TROUGHS...WHICH ADDED
SOME FUEL TO THE AFTERNOON CONVECTIVE CLOUDS/SHOWERS THERE. WATER
VAPOR IMAGERY SHOWS RIDGING ALOFT CENTERED OVER THE ISLANDS...WITH
VERY DRY UPPER LEVELS...YET BALLOON SOUNDINGS CONTINUE TO SHOW AN
ELEVATED INVERSION BASE NEAR 10 KFT...AND ABUNDANT MOISTURE BELOW
THIS CAP.

OVERNIGHT...SEA BREEZE-DRIVEN CLOUDS AND SHOWERS WILL PERSIST INTO
THE EARLY EVENING BEFORE DISSIPATING SHORTLY THEREAFTER. WITH THE
LOW LEVEL FLOW CONTINUING TO FAVOR AN ESE DIRECTION...A FEW SHOWERS
WILL MOVE ASHORE OVER E AND SE SHORES AND SLOPES...BUT A MOSTLY DRY
NIGHT IS EXPECTED AS THE BULK OF THE MOISTURE NEAR THE BIG ISLAND
MOVES ON A TRAJECTORY TO KEEP IT AWAY FROM THE OTHER ISLANDS. LIGHT
WINDS ALLOWED A GROUND-BASED INVERSION TO DEVELOP IN MANY AREAS LAST
NIGHT...WHICH IS USUALLY NOT TOO MUCH OF AN ISSUE...BUT SMOKE/ODORS
ASSOCIATED WITH A RELATIVELY NEW LAVA FLOW IN THE PUNA REGION BECAME
TRAPPED NEAR THE SURFACE BEFORE THE INVERSION BROKE BY MID-MORNING
TODAY. THE EXPECTATION IS THAT THIS WILL OCCUR AGAIN TONIGHT...BUT
TRADE WINDS SHOULD BE STRONG ENOUGH BY TUESDAY TO PREVENT THIS FROM
OCCURRING THEREAFTER.

A RELATIVELY DRY WEATHER PATTERN IS EXPECTED OVER THE NEXT COUPLE OF
DAYS. WINDS WILL SLOWLY BACK TO A MORE TYPICAL TRADE WIND
DIRECTION...AND STRENGTHEN SLIGHTLY...ON MONDAY AND TUESDAY AS THE
TROUGHS NEAR THE ISLANDS WEAKEN FURTHER AND MOVE NW...AND THE
SURFACE RIDGE TO THE N REBOUNDS SOMEWHAT. UNTIL THE TRADES FIRM
UP...WEATHER OVER LEEWARD AREAS WILL BE DRIVEN BY LAND AND SEA
BREEZES...WITH A MOSTLY CLEAR OVERNIGHT/MORNING...AND INCREASING
LATE MORNING CLOUDS LEADING TO A FEW AFTERNOON SHOWERS THAT
GRADUALLY CLEAR IN THE EVENING.

AS TRADE WINDS STRENGTHEN SOMEWHAT TUESDAY AND REMAIN LIGHT TO
MODERATE THROUGH THE WEEK...LEEWARD AREAS WILL BE MOSTLY DRY...WITH
BRIEF SHOWERS OVER WINDWARD AREAS. THE EXCEPTION IS LEEWARD BIG
ISLAND...WHERE CLOUDS AND A FEW SHOWERS WILL FAVOR AFTERNOON AND
EVENING HOURS BEFORE CLEARING LATE AT NIGHT. MID-LEVEL RIDGING
PERSISTING IN THE AREA WILL KEEP THE ISLAND ATMOSPHERE STABLE...AND
NO SIGNIFICANT MOISTURE SOURCES ARE EXPECTED THROUGH THURSDAY...THUS
RAINFALL TOTALS WILL BE ON THE LOW END. INCREASED MOISTURE LOOSELY
ASSOCIATED WITH THE REMNANT OF MARIE PASSING FAR NE OF THE ISLANDS
MAY INCREASE WINDWARD SHOWERS FROM THURSDAY NIGHT THROUGH SATURDAY...
WITH THIS SOLUTION SHARED BY BOTH THE GFS AND ECMWF.

&&

.AVIATION...
PERIODS OF MVFR CONDITIONS WILL IMPACT PHTO TERMINAL OVERNIGHT AS
SHOWERS AND CLOUDS MOVE INTO THE BIG ISLAND FROM THE SOUTHEAST...AND
AN AIRMET FOR MOUNTAIN OBSCURATION MAY BE NEEDED FROM HILO SOUTHWARD
ALONG THE PUNA AND KAU COASTS.

VFR CONDITIONS WILL PREVAIL ELSEWHERE TONIGHT AND MONDAY. CLOUDS AND
WIDELY SCATTERED SHOWERS SHOULD DEVELOP ONCE AGAIN MONDAY AFTERNOON
ALONG SEABREEZES ACROSS INTERIOR AND LEEWARD AREAS...WITH ISOLATED
MVFR CONDITIONS POSSIBLE.

&&

.MARINE...
ISSUED AT 345 PM

A MODEST REINFORCEMENT TO THE CURRENT S SWELL IS EXPECTED INTO
MONDAY...BUT IS NOT READILY APPARENT IN LATEST BUOY/SURF
OBSERVATIONS...WITH MOST OBSERVATIONS SHOWING LITTLE CHANGE OVER
THE PAST 24 HOURS OR SO. SURF ALONG S FACING SHORES IS EXPECTED TO
REMAIN BELOW ADVISORY LEVELS INTO TUESDAY...BUT A VERY LONG PERIOD
/20-25 SECOND/ S SWELL ARRIVING TUESDAY AND BUILDING THROUGH
WEDNESDAY WILL LIKELY PRODUCE ADVISORY LEVEL SURF ALONG S FACING
SHORES INTO THURSDAY. LONG PERIOD SWELL FROM THE E CONTINUES TO BE
OBSERVED...BUT SHOULD CONTINUE TO TREND DOWN THROUGH MONDAY. WINDS
AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR AT
LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION...M BALLARD
PREV DISCUSSION/MARINE...BIRCHARD
AVIATION...JACOBSON






000
FXHW60 PHFO 010146
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
345 PM HST SUN AUG 31 2014

.SYNOPSIS...
LIGHT EAST-SOUTHEAST WINDS WILL PREVAIL THROUGH LABOR DAY...WITH
LIGHT TO MODERATE TRADE WINDS EXPECTED FOR THE REMAINDER OF THE
WEEK. THE LIGHT WINDS WILL ALLOW AFTERNOON SEA BREEZES TO PRODUCE
LOCALIZED CLOUD BUILDUPS AND A FEW SHOWERS OVER LEEWARD AND
INTERIOR AREAS. AS TRADE WINDS STRENGTHEN SLIGHTLY...THE FOCUS FOR
LIMITED CLOUDS AND SHOWERS WILL SHIFT TO WINDWARD SLOPES AND COASTS.
TRADE SHOWERS MAY INCREASE BY FRIDAY AS UPSTREAM MOISTURE INCREASES.

&&

.DISCUSSION...
LATEST SATELLITE AND RADAR ANIMATIONS SHOW THE LOW-LEVEL FLOW NEAR
THE ISLANDS IS FROM THE ESE...EFFECTIVELY PLACING THE SMALLER
ISLANDS IN THE WIND SHADOW OF THE BIG ISLAND. A RELATIVELY WEAK 1026
MB SURFACE HIGH CENTERED ABOUT 1500 MILES NNE OF THE ISLANDS IS
DRIVING LIGHT TO MODERATE TRADE WINDS OVER THE TROPICAL CENTRAL N
PACIFIC...BUT WEAK LOW LEVEL TROUGHS NEAR THE ISLANDS HAVE WEAKENED
AND VEERED THE LOW LEVEL FLOW. WITH THE LIGHT WINDS...DAYTIME
HEATING OF THE ISLANDS LED TO SEA BREEZES WHICH DROVE CLOUD AND
SHOWER FORMATION OVER THE ISLANDS. ENHANCED MOISTURE NEAR THE BIG
ISLAND IS ASSOCIATED WITH ONE OF THESE PASSING TROUGHS...WHICH ADDED
SOME FUEL TO THE AFTERNOON CONVECTIVE CLOUDS/SHOWERS THERE. WATER
VAPOR IMAGERY SHOWS RIDGING ALOFT CENTERED OVER THE ISLANDS...WITH
VERY DRY UPPER LEVELS...YET BALLOON SOUNDINGS CONTINUE TO SHOW AN
ELEVATED INVERSION BASE NEAR 10 KFT...AND ABUNDANT MOISTURE BELOW
THIS CAP.

OVERNIGHT...SEA BREEZE-DRIVEN CLOUDS AND SHOWERS WILL PERSIST INTO
THE EARLY EVENING BEFORE DISSIPATING SHORTLY THEREAFTER. WITH THE
LOW LEVEL FLOW CONTINUING TO FAVOR AN ESE DIRECTION...A FEW SHOWERS
WILL MOVE ASHORE OVER E AND SE SHORES AND SLOPES...BUT A MOSTLY DRY
NIGHT IS EXPECTED AS THE BULK OF THE MOISTURE NEAR THE BIG ISLAND
MOVES ON A TRAJECTORY TO KEEP IT AWAY FROM THE OTHER ISLANDS. LIGHT
WINDS ALLOWED A GROUND-BASED INVERSION TO DEVELOP IN MANY AREAS LAST
NIGHT...WHICH IS USUALLY NOT TOO MUCH OF AN ISSUE...BUT SMOKE/ODORS
ASSOCIATED WITH A RELATIVELY NEW LAVA FLOW IN THE PUNA REGION BECAME
TRAPPED NEAR THE SURFACE BEFORE THE INVERSION BROKE BY MID-MORNING
TODAY. THE EXPECTATION IS THAT THIS WILL OCCUR AGAIN TONIGHT...BUT
TRADE WINDS SHOULD BE STRONG ENOUGH BY TUESDAY TO PREVENT THIS FROM
OCCURRING THEREAFTER.

A RELATIVELY DRY WEATHER PATTERN IS EXPECTED OVER THE NEXT COUPLE OF
DAYS. WINDS WILL SLOWLY BACK TO A MORE TYPICAL TRADE WIND
DIRECTION...AND STRENGTHEN SLIGHTLY...ON MONDAY AND TUESDAY AS THE
TROUGHS NEAR THE ISLANDS WEAKEN FURTHER AND MOVE NW...AND THE
SURFACE RIDGE TO THE N REBOUNDS SOMEWHAT. UNTIL THE TRADES FIRM
UP...WEATHER OVER LEEWARD AREAS WILL BE DRIVEN BY LAND AND SEA
BREEZES...WITH A MOSTLY CLEAR OVERNIGHT/MORNING...AND INCREASING
LATE MORNING CLOUDS LEADING TO A FEW AFTERNOON SHOWERS THAT
GRADUALLY CLEAR IN THE EVENING.

AS TRADE WINDS STRENGTHEN SOMEWHAT TUESDAY AND REMAIN LIGHT TO
MODERATE THROUGH THE WEEK...LEEWARD AREAS WILL BE MOSTLY DRY...WITH
BRIEF SHOWERS OVER WINDWARD AREAS. THE EXCEPTION IS LEEWARD BIG
ISLAND...WHERE CLOUDS AND A FEW SHOWERS WILL FAVOR AFTERNOON AND
EVENING HOURS BEFORE CLEARING LATE AT NIGHT. MID-LEVEL RIDGING
PERSISTING IN THE AREA WILL KEEP THE ISLAND ATMOSPHERE STABLE...AND
NO SIGNIFICANT MOISTURE SOURCES ARE EXPECTED THROUGH THURSDAY...THUS
RAINFALL TOTALS WILL BE ON THE LOW END. INCREASED MOISTURE LOOSELY
ASSOCIATED WITH THE REMNANT OF MARIE PASSING FAR NE OF THE ISLANDS
MAY INCREASE WINDWARD SHOWERS FROM THURSDAY NIGHT THROUGH SATURDAY...
WITH THIS SOLUTION SHARED BY BOTH THE GFS AND ECMWF.

&&

.AVIATION...
PREVAILING VFR ALL AREAS THROUGH TOMORROW. ISOLATED MVFR CONDS
POSSIBLE IN PASSING SHOWERS...MAINLY WINDWARD AND MOUNTAIN AREAS OF
THE BIG ISLAND. MILD SEA BREEZES THIS AFTERNOON WILL GIVE WAY TO
WEAK LAND BREEZES AFTER SUNSET. SHOWERS WILL TAPER OFF THIS EVENING
OVER LEEWARD AREAS BUT PERSIST OVERNIGHT ALONG WINDWARD SLOPES.

A POTENTIAL FOR MT OBSCN EXISTS ALONG SOUTHEASTERN PORTIONS OF THE
BIG ISLAND OVERNIGHT.

&&

.MARINE...
A MODEST REINFORCEMENT TO THE CURRENT S SWELL IS EXPECTED INTO
MONDAY...BUT IS NOT READILY APPARENT IN LATEST BUOY/SURF
OBSERVATIONS...WITH MOST OBSERVATIONS SHOWING LITTLE CHANGE OVER
THE PAST 24 HOURS OR SO. SURF ALONG S FACING SHORES IS EXPECTED TO
REMAIN BELOW ADVISORY LEVELS INTO TUESDAY...BUT A VERY LONG PERIOD
/20-25 SECOND/ S SWELL ARRIVING TUESDAY AND BUILDING THROUGH
WEDNESDAY WILL LIKELY PRODUCE ADVISORY LEVEL SURF ALONG S FACING
SHORES INTO THURSDAY. LONG PERIOD SWELL FROM THE E CONTINUES TO BE
OBSERVED...BUT SHOULD CONTINUE TO TREND DOWN THROUGH MONDAY. WINDS
AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR AT
LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...BEDAL







000
FXHW60 PHFO 312006
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1005 AM HST SUN AUG 31 2014

.SYNOPSIS...
LIGHT WINDS WILL PREVAIL THROUGH THE HOLIDAY WEEKEND...DELIVERING A
FEW CLOUDS AND SHOWERS TO WINDWARD AREAS...MAINLY DURING NIGHTS AND
MORNINGS. THE LIGHT WINDS WILL ALSO ALLOW AFTERNOON SEA BREEZES TO
PRODUCE LOCALIZED CLOUD BUILDUPS AND A FEW SHOWERS OVER LEEWARD AND
INTERIOR AREAS. SLIGHTLY STRONGER TRADE WINDS ARE EXPECTED BY
MID-WEEK.

&&

.DISCUSSION...
LATEST SATELLITE AND RADAR ANIMATIONS SHOW THE LOW-LEVEL FLOW NEAR
THE ISLANDS HAS VEERED TO THE ESE...EFFECTIVELY PLACING THE SMALLER
ISLANDS IN THE WIND SHADOW OF THE BIG ISLAND. DESPITE A FAIR AMOUNT
OF LOW CLOUDS OVER THE NEAR SHORE WATERS...SKIES OVER MOST ISLAND
AREAS ARE SUNNY THIS MORNING...WITH LIGHT WINDS PREVAILING. A
RELATIVELY WEAK 1025 MB SURFACE HIGH CENTERED ABOUT 1400 MILES NNE
OF THE ISLANDS IS DRIVING LIGHT TO MODERATE TRADE WINDS OVER THE
TROPICAL CENTRAL N PACIFIC...BUT WEAK AND POORLY DEFINED LOW LEVEL
TROUGHS NEAR THE ISLANDS HAVE WEAKENED AND VEERED THE LOW LEVEL
FLOW. THE LIGHT WINDS ALLOWED A GROUND-BASED INVERSION TO DEVELOP IN
MANY AREAS OVERNIGHT...WHICH IS USUALLY NOT TOO MUCH OF AN ISSUE...
BUT SMOKE ASSOCIATED WITH A RELATIVELY NEW LAVA FLOW IN THE PUNA
REGION BECAME TRAPPED NEAR THE SURFACE OVERNIGHT. WATER VAPOR
IMAGERY SHOWS RIDGING ALOFT CENTERED OVER THE ISLANDS...WITH VERY
DRY UPPER LEVELS...YET MORNING SOUNDINGS SHOWED AN ELEVATED
INVERSION BASE NEAR 10 KFT AND ABUNDANT MOISTURE BELOW THIS CAP.

THE FORECAST FOR TODAY HAS BEEN UPDATED TO ACCOUNT FOR LATEST
OBSERVATIONS...AND TO INCREASE THE AFTERNOON POPS OVER LEEWARD
AREAS. WITH WINDS AS LIGHT AS THEY ARE AND THE ABUNDANT HEATING OF
THE ISLANDS THIS MORNING...SEA BREEZE CONVECTION IS EXPECTED TO BE
STRONGER TODAY THAN THE PAST SEVERAL DAYS. THERE IS THE POSSIBILITY
OF ISOLATED BRIEFLY HEAVY SHOWERS...MAINLY OVER LEEWARD COASTS AND
SLOPES...AND ESPECIALLY OVER SW MAUI...WHERE SHOWERS HAVE SOAKED THE
ULUPALAKUA AREA THE LAST 2 AFTERNOONS.

DESPITE THE EXPECTED POP-UP SHOWERS TODAY...A RELATIVELY DRY WEATHER
PATTERN IS EXPECTED OVER THE NEXT COUPLE OF DAYS. WINDS WILL BACK TO
A MORE TYPICAL TRADE WIND DIRECTION AND STRENGTHEN SLIGHTLY ON
MONDAY AND TUESDAY AS WEAK TROUGHS NEAR THE ISLANDS WEAKEN AND MOVE
NW...AND THE SURFACE RIDGE TO THE N REBOUNDS SOMEWHAT. DESPITE
THIS...A HYBRID TRADE WIND PATTERN IS EXPECTED TONIGHT AND
MONDAY...WITH LIGHT TRADE WINDS DELIVERING A FEW SHOWERS TO
WINDWARD AREAS AT NIGHT AND IN THE MORNING. WEATHER OVER LEEWARD
AREAS WILL BE DRIVEN BY LAND AND SEA BREEZES...WITH A MOSTLY CLEAR
NIGHT AND MORNING...WITH INCREASING LATE MORNING CLOUDS LEADING TO A
FEW AFTERNOON SHOWERS THAT GRADUALLY CLEAR IN THE EVENING. AS TRADE
WINDS STRENGTHEN SOMEWHAT TUESDAY AND REMAIN LIGHT TO MODERATE
THROUGH THE WEEK...LEEWARD AREAS WILL BE MOSTLY DRY...WITH BRIEF
SHOWERS OVER WINDWARD AREAS. THE EXCEPTION IS LEEWARD BIG
ISLAND...WHERE CLOUDS AND A FEW SHOWERS WILL FAVOR AFTERNOON AND
EVENING HOURS BEFORE CLEARING LATE AT NIGHT. MID-LEVEL RIDGING
PERSISTING IN THE AREA WILL KEEP THE ISLAND ATMOSPHERE STABLE...AND
NO SIGNIFICANT MOISTURE SOURCES ARE EXPECTED THROUGH THURSDAY...THUS
RAINFALL TOTALS WILL BE ON THE LOW END. INCREASED MOISTURE LOOSELY
ASSOCIATED WITH THE REMNANT OF MARIE PASSING FAR NE OF THE ISLANDS
MAY INCREASE TRADE SHOWERS FROM THURSDAY NIGHT THROUGH SATURDAY...
WITH THIS SOLUTION SHARED BY BOTH THE GFS AND ECMWF.

&&

.AVIATION...
PREVAILING VFR EXPECTED ALL AREAS TODAY. ISOLATED MVFR CONDS
POSSIBLE IN PASSING SHOWERS THIS MORNING...MAINLY WINDWARD AND
MOUNTAIN AREAS. WEAK TRADE WIND FLOW WILL ALLOW FOR THE DEVELOPMENT
OF SEA BREEZES MOST AREAS THIS AFTERNOON. THESE SEA BREEZES WILL
ACT TO FOCUS AFTERNOON SHOWER ACTIVITY OVER INLAND AREAS. BOTH SEA
BREEZES AND LEEWARD SHOWERS WILL TAPER OFF AFTER SUNSET.

&&

.MARINE...
A REINFORCEMENT TO OUR CURRENT S SWELL IS EXPECTED TODAY...BUT IS
NOT READILY APPARENT IN LATEST BUOY/SURF OBSERVATIONS. REGARDLESS...
SURF ALONG S FACING SHORES IS EXPECTED TO REMAIN BELOW ADVISORY
LEVELS INTO TUESDAY. A VERY LONG PERIOD /20-25 SECOND/ S SWELL
ARRIVING TUESDAY AND BUILDING THROUGH WEDNESDAY WILL LIKELY PRODUCE
ADVISORY LEVEL SURF ALONG S FACING SHORES INTO THURSDAY. LONG PERIOD
SWELL FROM THE E CONTINUES TO BE OBSERVED...BUT SHOULD CONTINUE TO
TREND DOWN THROUGH MONDAY. WINDS AND SEAS WILL REMAIN BELOW SMALL
CRAFT ADVISORY THRESHOLDS FOR AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...BEDAL







000
FXHW60 PHFO 312006
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1005 AM HST SUN AUG 31 2014

.SYNOPSIS...
LIGHT WINDS WILL PREVAIL THROUGH THE HOLIDAY WEEKEND...DELIVERING A
FEW CLOUDS AND SHOWERS TO WINDWARD AREAS...MAINLY DURING NIGHTS AND
MORNINGS. THE LIGHT WINDS WILL ALSO ALLOW AFTERNOON SEA BREEZES TO
PRODUCE LOCALIZED CLOUD BUILDUPS AND A FEW SHOWERS OVER LEEWARD AND
INTERIOR AREAS. SLIGHTLY STRONGER TRADE WINDS ARE EXPECTED BY
MID-WEEK.

&&

.DISCUSSION...
LATEST SATELLITE AND RADAR ANIMATIONS SHOW THE LOW-LEVEL FLOW NEAR
THE ISLANDS HAS VEERED TO THE ESE...EFFECTIVELY PLACING THE SMALLER
ISLANDS IN THE WIND SHADOW OF THE BIG ISLAND. DESPITE A FAIR AMOUNT
OF LOW CLOUDS OVER THE NEAR SHORE WATERS...SKIES OVER MOST ISLAND
AREAS ARE SUNNY THIS MORNING...WITH LIGHT WINDS PREVAILING. A
RELATIVELY WEAK 1025 MB SURFACE HIGH CENTERED ABOUT 1400 MILES NNE
OF THE ISLANDS IS DRIVING LIGHT TO MODERATE TRADE WINDS OVER THE
TROPICAL CENTRAL N PACIFIC...BUT WEAK AND POORLY DEFINED LOW LEVEL
TROUGHS NEAR THE ISLANDS HAVE WEAKENED AND VEERED THE LOW LEVEL
FLOW. THE LIGHT WINDS ALLOWED A GROUND-BASED INVERSION TO DEVELOP IN
MANY AREAS OVERNIGHT...WHICH IS USUALLY NOT TOO MUCH OF AN ISSUE...
BUT SMOKE ASSOCIATED WITH A RELATIVELY NEW LAVA FLOW IN THE PUNA
REGION BECAME TRAPPED NEAR THE SURFACE OVERNIGHT. WATER VAPOR
IMAGERY SHOWS RIDGING ALOFT CENTERED OVER THE ISLANDS...WITH VERY
DRY UPPER LEVELS...YET MORNING SOUNDINGS SHOWED AN ELEVATED
INVERSION BASE NEAR 10 KFT AND ABUNDANT MOISTURE BELOW THIS CAP.

THE FORECAST FOR TODAY HAS BEEN UPDATED TO ACCOUNT FOR LATEST
OBSERVATIONS...AND TO INCREASE THE AFTERNOON POPS OVER LEEWARD
AREAS. WITH WINDS AS LIGHT AS THEY ARE AND THE ABUNDANT HEATING OF
THE ISLANDS THIS MORNING...SEA BREEZE CONVECTION IS EXPECTED TO BE
STRONGER TODAY THAN THE PAST SEVERAL DAYS. THERE IS THE POSSIBILITY
OF ISOLATED BRIEFLY HEAVY SHOWERS...MAINLY OVER LEEWARD COASTS AND
SLOPES...AND ESPECIALLY OVER SW MAUI...WHERE SHOWERS HAVE SOAKED THE
ULUPALAKUA AREA THE LAST 2 AFTERNOONS.

DESPITE THE EXPECTED POP-UP SHOWERS TODAY...A RELATIVELY DRY WEATHER
PATTERN IS EXPECTED OVER THE NEXT COUPLE OF DAYS. WINDS WILL BACK TO
A MORE TYPICAL TRADE WIND DIRECTION AND STRENGTHEN SLIGHTLY ON
MONDAY AND TUESDAY AS WEAK TROUGHS NEAR THE ISLANDS WEAKEN AND MOVE
NW...AND THE SURFACE RIDGE TO THE N REBOUNDS SOMEWHAT. DESPITE
THIS...A HYBRID TRADE WIND PATTERN IS EXPECTED TONIGHT AND
MONDAY...WITH LIGHT TRADE WINDS DELIVERING A FEW SHOWERS TO
WINDWARD AREAS AT NIGHT AND IN THE MORNING. WEATHER OVER LEEWARD
AREAS WILL BE DRIVEN BY LAND AND SEA BREEZES...WITH A MOSTLY CLEAR
NIGHT AND MORNING...WITH INCREASING LATE MORNING CLOUDS LEADING TO A
FEW AFTERNOON SHOWERS THAT GRADUALLY CLEAR IN THE EVENING. AS TRADE
WINDS STRENGTHEN SOMEWHAT TUESDAY AND REMAIN LIGHT TO MODERATE
THROUGH THE WEEK...LEEWARD AREAS WILL BE MOSTLY DRY...WITH BRIEF
SHOWERS OVER WINDWARD AREAS. THE EXCEPTION IS LEEWARD BIG
ISLAND...WHERE CLOUDS AND A FEW SHOWERS WILL FAVOR AFTERNOON AND
EVENING HOURS BEFORE CLEARING LATE AT NIGHT. MID-LEVEL RIDGING
PERSISTING IN THE AREA WILL KEEP THE ISLAND ATMOSPHERE STABLE...AND
NO SIGNIFICANT MOISTURE SOURCES ARE EXPECTED THROUGH THURSDAY...THUS
RAINFALL TOTALS WILL BE ON THE LOW END. INCREASED MOISTURE LOOSELY
ASSOCIATED WITH THE REMNANT OF MARIE PASSING FAR NE OF THE ISLANDS
MAY INCREASE TRADE SHOWERS FROM THURSDAY NIGHT THROUGH SATURDAY...
WITH THIS SOLUTION SHARED BY BOTH THE GFS AND ECMWF.

&&

.AVIATION...
PREVAILING VFR EXPECTED ALL AREAS TODAY. ISOLATED MVFR CONDS
POSSIBLE IN PASSING SHOWERS THIS MORNING...MAINLY WINDWARD AND
MOUNTAIN AREAS. WEAK TRADE WIND FLOW WILL ALLOW FOR THE DEVELOPMENT
OF SEA BREEZES MOST AREAS THIS AFTERNOON. THESE SEA BREEZES WILL
ACT TO FOCUS AFTERNOON SHOWER ACTIVITY OVER INLAND AREAS. BOTH SEA
BREEZES AND LEEWARD SHOWERS WILL TAPER OFF AFTER SUNSET.

&&

.MARINE...
A REINFORCEMENT TO OUR CURRENT S SWELL IS EXPECTED TODAY...BUT IS
NOT READILY APPARENT IN LATEST BUOY/SURF OBSERVATIONS. REGARDLESS...
SURF ALONG S FACING SHORES IS EXPECTED TO REMAIN BELOW ADVISORY
LEVELS INTO TUESDAY. A VERY LONG PERIOD /20-25 SECOND/ S SWELL
ARRIVING TUESDAY AND BUILDING THROUGH WEDNESDAY WILL LIKELY PRODUCE
ADVISORY LEVEL SURF ALONG S FACING SHORES INTO THURSDAY. LONG PERIOD
SWELL FROM THE E CONTINUES TO BE OBSERVED...BUT SHOULD CONTINUE TO
TREND DOWN THROUGH MONDAY. WINDS AND SEAS WILL REMAIN BELOW SMALL
CRAFT ADVISORY THRESHOLDS FOR AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...BEDAL






000
FXHW60 PHFO 311330
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST SUN AUG 31 2014

.SYNOPSIS...
LIGHT TRADE WINDS WILL PREVAIL THROUGH THE HOLIDAY WEEKEND...
DELIVERING A FEW CLOUDS AND SHOWERS TO WINDWARD AREAS...MAINLY
DURING NIGHTS AND MORNINGS. THE LIGHT WINDS WILL ALSO ALLOW
AFTERNOON SEA BREEZES TO PRODUCE LOCALIZED CLOUD BUILDUPS AND A FEW
SHOWERS OVER LEEWARD AND INTERIOR AREAS.

&&

.DISCUSSION...
HIGH PRESSURE FAR NORTH OF THE STATE WILL CONTINUE TO BRING A TRADE
WIND FLOW TO THE REGION THROUGH THE WEEKEND. THE MODELS ARE IN GOOD
AGREEMENT WITH THE HIGH MOVING TO THE EAST THROUGHOUT THE
WEEKEND...AND THEN SLOWLY LIFTING TO THE NORTH. A NORTH TO SOUTH
ORIENTED WEAKENING SURFACE TROUGH REMAINS NEAR THE CENTRAL ISLANDS
OVERNIGHT...BRINGING SOME CLOUDS AND SHOWERS MAINLY TO THE WATERS TO
THE NORTHEAST. THIS TROUGH HAS BEEN MOVING TO WEST...OVERNIGHT AND
THAT MOVEMENT IS EXPECTED TO CONTINUE TODAY.

ANOTHER LOW LEVEL TROUGH...ORIENTED SOUTHWEST TO NORTHEAST...WAS
SOUTH OF THE BIG ISLAND OVERNIGHT. SOME OF THE CLOUDS AND SHOWERS
ASSOCIATED WITH THIS SYSTEM MAY IMPACT THE BIG ISLAND LATER TODAY
AND TONIGHT.

LOW CLOUDS NEAR THE ISLANDS ARE MOVING FROM AN EASTERLY DIRECTION IN
THE TRADE WIND FLOW. THE TROUGHS...COMBINED WITH A SURFACE LOW ABOUT
1500 MILES NORTHEAST OF HONOLULU ARE HELPING TO DISRUPT THE TRADE
WIND FLOW OVER THE ISLANDS. OVER THE LAST COUPLE OF DAYS...THIS HAS
RESULTED IN SOME AREAS EXPERIENCING AFTERNOON SEA BREEZES...WHICH
BROUGHT SOME MORE CLOUDS TO THE INTERIOR OF THE ISLANDS DURING THE
AFTERNOON. AS THESE SYSTEMS EDGE CLOSER TO THE ISLANDS...WE EXPECT
MORE AREAS TODAY TO EXPERIENCE SOME AFTERNOON SEA BREEZES.

THE GLOBAL MODELS ARE IN GOOD AGREEMENT WITH LITTLE CHANGE IN THE
WIND PATTERN INTO NEXT WEEK. WHILE THE HIGH REMAINS FAR TO THE
NORTHEAST...AND A SURFACE RIDGE REMAINS OVER THE ISLANDS...THE GFS
AND ECMWF BOTH SHOW DISRUPTIONS IN THE LOW LEVEL FLOW THAT COULD
PREVENT MODERATE TRADES FROM BUILDING BACK IN. AS THE RESULT OF THE
LAST FEW MODEL RUNS SHOWING THIS TREND...HAVE BACKED OFF A BIT ON
THE WIND SPEEDS FOR THE MIDDLE AND END OF THE WEEK.

A FEW SHOWERS TODAY AND TONIGHT WILL BE THE RESULT OF THE NEARBY
TROUGH. THE MIDDLE PART OF THE WEEK LOOKS TO BE ON THE DRIER
SIDE...WITH ADDITIONAL LOW LEVEL MOISTURE RIDING IN ON THE LIGHT
TRADES FOR THE END OF THE WEEK.

&&

.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS THE STATE TODAY AND TONIGHT.
BRIEF PERIODS OF MVFR WILL BE POSSIBLE WITH PASSING SHOWERS
ACROSS WINDWARD SECTIONS INTO THIS MORNING...AND ACROSS
LEEWARD/INTERIOR AREAS AS WIDELY SCATTERED SHOWERS DEVELOP ALONG
SEABREEZES THIS AFTERNOON.

NO AIRMETS ARE IN EFFECT AT THIS TIME. THERE IS A SMALL CHANCE THAT
AIRMET SIERRA FOR MOUNTAIN OBSCURATION COULD BECOME NECESSARY IF A
MORE PERSISTENT OR WIDESPREAD AREA OF SHOWERS/CLOUDS DEVELOPS.

&&

.MARINE...
THE NEAR SHORE BUOYS HAVE SHOWN A SLOW DECREASING TREND IN THE SWELL
FOR THE SOUTH FACING SHORES. SURF ALONG SOUTH FACING SHORES IS
EXPECTED TO REMAIN BELOW ADVISORY LEVELS THROUGH MONDAY. A VERY LONG
PERIOD /20-25 SECOND/ SOUTH SWELL ARRIVING TUESDAY AND BUILDING
THROUGH WEDNESDAY WILL LIKELY PRODUCE ADVISORY LEVEL SURF INTO
THURSDAY.

THE SWELL FROM THE EAST HAS REMAINED NEARLY STEADY OVER THE LAST
COUPLE OF HOURS. SURF ALONG EAST FACING SHORES IS ALSO EXPECTED TO
REMAIN BELOW ADVISORY LEVELS.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...M BALLARD
AVIATION...JACOBSON









000
FXHW60 PHFO 311330
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST SUN AUG 31 2014

.SYNOPSIS...
LIGHT TRADE WINDS WILL PREVAIL THROUGH THE HOLIDAY WEEKEND...
DELIVERING A FEW CLOUDS AND SHOWERS TO WINDWARD AREAS...MAINLY
DURING NIGHTS AND MORNINGS. THE LIGHT WINDS WILL ALSO ALLOW
AFTERNOON SEA BREEZES TO PRODUCE LOCALIZED CLOUD BUILDUPS AND A FEW
SHOWERS OVER LEEWARD AND INTERIOR AREAS.

&&

.DISCUSSION...
HIGH PRESSURE FAR NORTH OF THE STATE WILL CONTINUE TO BRING A TRADE
WIND FLOW TO THE REGION THROUGH THE WEEKEND. THE MODELS ARE IN GOOD
AGREEMENT WITH THE HIGH MOVING TO THE EAST THROUGHOUT THE
WEEKEND...AND THEN SLOWLY LIFTING TO THE NORTH. A NORTH TO SOUTH
ORIENTED WEAKENING SURFACE TROUGH REMAINS NEAR THE CENTRAL ISLANDS
OVERNIGHT...BRINGING SOME CLOUDS AND SHOWERS MAINLY TO THE WATERS TO
THE NORTHEAST. THIS TROUGH HAS BEEN MOVING TO WEST...OVERNIGHT AND
THAT MOVEMENT IS EXPECTED TO CONTINUE TODAY.

ANOTHER LOW LEVEL TROUGH...ORIENTED SOUTHWEST TO NORTHEAST...WAS
SOUTH OF THE BIG ISLAND OVERNIGHT. SOME OF THE CLOUDS AND SHOWERS
ASSOCIATED WITH THIS SYSTEM MAY IMPACT THE BIG ISLAND LATER TODAY
AND TONIGHT.

LOW CLOUDS NEAR THE ISLANDS ARE MOVING FROM AN EASTERLY DIRECTION IN
THE TRADE WIND FLOW. THE TROUGHS...COMBINED WITH A SURFACE LOW ABOUT
1500 MILES NORTHEAST OF HONOLULU ARE HELPING TO DISRUPT THE TRADE
WIND FLOW OVER THE ISLANDS. OVER THE LAST COUPLE OF DAYS...THIS HAS
RESULTED IN SOME AREAS EXPERIENCING AFTERNOON SEA BREEZES...WHICH
BROUGHT SOME MORE CLOUDS TO THE INTERIOR OF THE ISLANDS DURING THE
AFTERNOON. AS THESE SYSTEMS EDGE CLOSER TO THE ISLANDS...WE EXPECT
MORE AREAS TODAY TO EXPERIENCE SOME AFTERNOON SEA BREEZES.

THE GLOBAL MODELS ARE IN GOOD AGREEMENT WITH LITTLE CHANGE IN THE
WIND PATTERN INTO NEXT WEEK. WHILE THE HIGH REMAINS FAR TO THE
NORTHEAST...AND A SURFACE RIDGE REMAINS OVER THE ISLANDS...THE GFS
AND ECMWF BOTH SHOW DISRUPTIONS IN THE LOW LEVEL FLOW THAT COULD
PREVENT MODERATE TRADES FROM BUILDING BACK IN. AS THE RESULT OF THE
LAST FEW MODEL RUNS SHOWING THIS TREND...HAVE BACKED OFF A BIT ON
THE WIND SPEEDS FOR THE MIDDLE AND END OF THE WEEK.

A FEW SHOWERS TODAY AND TONIGHT WILL BE THE RESULT OF THE NEARBY
TROUGH. THE MIDDLE PART OF THE WEEK LOOKS TO BE ON THE DRIER
SIDE...WITH ADDITIONAL LOW LEVEL MOISTURE RIDING IN ON THE LIGHT
TRADES FOR THE END OF THE WEEK.

&&

.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS THE STATE TODAY AND TONIGHT.
BRIEF PERIODS OF MVFR WILL BE POSSIBLE WITH PASSING SHOWERS
ACROSS WINDWARD SECTIONS INTO THIS MORNING...AND ACROSS
LEEWARD/INTERIOR AREAS AS WIDELY SCATTERED SHOWERS DEVELOP ALONG
SEABREEZES THIS AFTERNOON.

NO AIRMETS ARE IN EFFECT AT THIS TIME. THERE IS A SMALL CHANCE THAT
AIRMET SIERRA FOR MOUNTAIN OBSCURATION COULD BECOME NECESSARY IF A
MORE PERSISTENT OR WIDESPREAD AREA OF SHOWERS/CLOUDS DEVELOPS.

&&

.MARINE...
THE NEAR SHORE BUOYS HAVE SHOWN A SLOW DECREASING TREND IN THE SWELL
FOR THE SOUTH FACING SHORES. SURF ALONG SOUTH FACING SHORES IS
EXPECTED TO REMAIN BELOW ADVISORY LEVELS THROUGH MONDAY. A VERY LONG
PERIOD /20-25 SECOND/ SOUTH SWELL ARRIVING TUESDAY AND BUILDING
THROUGH WEDNESDAY WILL LIKELY PRODUCE ADVISORY LEVEL SURF INTO
THURSDAY.

THE SWELL FROM THE EAST HAS REMAINED NEARLY STEADY OVER THE LAST
COUPLE OF HOURS. SURF ALONG EAST FACING SHORES IS ALSO EXPECTED TO
REMAIN BELOW ADVISORY LEVELS.

WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS FOR
AT LEAST THE NEXT SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION/MARINE...M BALLARD
AVIATION...JACOBSON










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