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000
FXHW60 PHFO 231405
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
405 AM HST SAT MAY 23 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE SOUTH OF MAUI COUNTY THIS MORNING...
THEN ACROSS THE BIG ISLAND LATER TODAY AND TONIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. MODERATE NORTH TO
NORTHEAST WINDS WILL PREVAIL BEHIND THE FRONT FROM TODAY THROUGH
SUNDAY...WITH SHOWER ACTIVITY FOCUSED MAINLY ON WINDWARD COASTS
AND SLOPES. A CLOUD BAND MOVING OVER THE ISLANDS FROM THE NORTH
ON SUNDAY MAY ENHANCE THE WINDWARD SHOWERS SOMEWHAT. LIGHTER
NORTHEAST WINDS ARE EXPECTED FOR MONDAY...WITH LIGHT BACKGROUND
FLOW AND A RETURN TO A LAND AND SEA BREEZE PATTERN FORECAST FOR
TUESDAY THROUGH THURSDAY.

&&

.DISCUSSION...
AN INCREASINGLY DIFFUSE COLD FRONT LIES ACROSS MAUI COUNTY
CURRENTLY...WITH SHOWER ACTIVITY ALONG AND AHEAD OF THE FRONT
AFFECTING WINDWARD MAUI AND APPROACHING THE HAMAKUA COAST OF THE
BIG ISLAND. PERSISTENT MODERATE TO OCCASIONALLY HEAVY RAINS
ANCHORED ON THE NORTH/NORTHEAST FACING SLOPES REQUIRED SEVERAL
FLOOD ADVISORIES TO BE ISSUED DURING THE NIGHT...WITH SEVERAL
STREAM GAUGES ON MOLOKAI AND MAUI EARLIER SHOWING MODEST WATER
LEVEL RISES. DRIER NORTHERLY FLOW PREVAILS ACROSS OAHU AND KAUAI
BEHIND THE FRONT. SURFACE ANALYSIS DEPICTS THE AFOREMENTIONED
FRONT STRETCHING SW FROM A LOW CENTERED ABOUT 900 MILES NNE OF
PHNL...WITH A 1026 MB HIGH CENTERED ABOUT 1000 MILES NW OF KAUAI.
AN UNSEASONABLY DEEP TROUGH ALOFT IS LOCATED OVER THE CENTRAL
PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT OF THE SURFACE FRONT
SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN LATE MAY. MIMIC-TPW
SATELLITE IMAGERY DEPICTS A NARROW BAND OF ENHANCED MOISTURE ALONG
THE FRONT...WITH ESTIMATED PWATS UP TO 1.5 INCHES. THE 12Z LIHUE
SOUNDING REFLECTED THE DRIER AIRMASS BEHIND THE FRONT...WITH THE
INVERSION DOWN TO 5K FEET AND PWAT OF 0.99 INCHES. THERE HAS BEEN
LITTLE AIRMASS CHANGE DURING THE PAST 12 HOURS AT HILO AHEAD OF
THE FRONT...WITH THE INVERSION STILL AROUND 9K FEET AND PWAT OF
1.28 INCHES.

FOR TODAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING SOUTHWARD
FROM MAUI ACROSS THE BIG ISLAND. SHOWERS WILL MAINLY AFFECT
WINDWARD AREAS...ALTHOUGH THE DEEPER MOISTURE ALONG THE FRONT
WILL PROBABLY ALLOW SCATTERED SHOWERS TO DEVELOP ALONG THE KONA
COAST DURING THE AFTERNOON. DRIER NNE FLOW WILL PREVAIL ACROSS
KAUAI AND OAHU...WITH IMPROVING CONDITIONS SPREADING INTO MAUI
COUNTY DURING THE DAY. A SLIGHTLY DRIER AND COOLER AIR MASS HAS
SPREAD INTO THE WESTERN END OF THE STATE BEHIND THE FRONT...WITH
DEW POINTS HAVING ALREADY DROPPED INTO THE LOWER 60S. HIGH TEMPS
SHOULD BE A COUPLE OF DEGREES COOLER THIS WEEKEND THAN THEY HAVE
BEEN RECENTLY FOR MOST AREAS.

THE PARENT LOW OF THE FRONT WILL MOVE SOUTH AND WEAKEN THROUGH THE
WEEKEND...AS HIGH PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL
KEEP A RELATIVELY COOL MODERATE N/NE WIND FLOW OVER THE STATE
TONIGHT AND SUNDAY. SHALLOW BANDS OF MOISTURE ROTATING AROUND THE
LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH AND EAST FACING
SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH
THE PERIOD. GFS CONTINUES TO INDICATE THAT A WEAK BAND OF ENHANCED
MOISTURE WILL MOVE ACROSS THE STATE SUNDAY INTO SUNDAY EVENING.
LIGHT NE FLOW SHOULD HOLD THROUGH MONDAY...BUT THEN IS FORECAST TO
WEAKEN FURTHER TUESDAY THROUGH THURSDAY AS LOW PRESSURE LINGERS
FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO OUR NORTHWEST. THIS
WILL LIKELY ALLOW LAND AND SEA BREEZES TO DOMINATE THE LOCAL
WEATHER REGIME ONCE AGAIN....WITH AFTERNOON CLOUDS AND SHOWERS
ACROSS THE INTERIOR/LEEWARD AREAS OF THE ISLANDS. THE LOW SHOULD
FINALLY EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING A
WEAK HIGH PRESSURE RIDGE TO BUILD TO OUR NORTH...AND BRINGING
LIGHT TO MODERATE TRADES BACK ACROSS THE STATE.

&&

.AVIATION...
A WEAKENING COLD FRONT ACROSS MAUI COUNTY WILL SHIFT SOUTHEASTWARD
AND INTO THE BIG ISLAND THIS MORNING...AND PUSH SOUTH OF STATE
TONIGHT. TEMPORARY MVFR CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS
AS THE FRONT MOVES THROUGH...WITH IMPROVING CONDITIONS EXPECTED
BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS MOLOKAI
LANAI AND MAUI...AND THESE CONDITIONS SHOULD IMPROVE AROUND
DAYBREAK. AN AIRMET MAY BE NEEDED ACROSS THE BIG ISLAND LATER THIS
MORNING FOR MOUNTAIN OBSCURATION AS WELL.

&&

.MARINE...
THE FRIDAY EVENING ASCAT PASS FOUND AREAS OF 20 KT WINDS ACROSS
THE WESTERN HAWAIIAN COASTAL WATERS...BEHIND THE ADVANCING COLD
FRONT. A SMALL CRAFT ADVISORY /SCA/ REMAINS IN EFFECT FOR THE
LEEWARD KAUAI COASTAL WATERS THROUGH TODAY...WITH 25 KT WINDS
POSSIBLE MAINLY ACROSS THE KAULAKAHI CHANNEL. MODERATE TO FRESH
N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD THROUGH THE REMAINDER OF
THE COASTAL WATERS AROUND THE BIG ISLAND TODAY...AND PREVAIL
STATEWIDE TONIGHT AND SUNDAY. WINDS ARE FORECAST TO REMAIN BELOW
SCA LEVELS AT THIS POINT...BUT MAY COME CLOSE IN SOME AREAS
EXPOSED TO THE NNE WIND DIRECTION. WINDS WILL THEN WEAKEN ONCE
AGAIN MONDAY...BECOMING LIGHT WITH AFTERNOON SEABREEZES LIKELY
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF SOUTH SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP
SOUTH PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF
TO SOUTH FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO
REMAIN BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT
OVERLAPPING SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO
NEAR ADVISORY-LEVELS ALONG EXPOSED SOUTH FACING SHORES. A
MODERATE NNE SWELL IS EXPECTED TO ARRIVE ON SUNDAY AND LINGER
THROUGH MONDAY...BUT RELATIVELY SHORT SWELL PERIODS SHOULD RESULT
IN SURF WELL BELOW ADVISORY LEVELS ON NORTH FACING SHORES.
OTHERWISE...A COUPLE OF SMALL SWELLS FROM THE NNW AND WNW ARE
EXPECTED OVER THE WEEKEND AND EARLY NEXT WEEK...WITH RESULTANT
SURF WELL BELOW ADVISORY LEVELS. SEE THE LATEST OAHU SURF
DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON HST TODAY FOR BIG ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR KAUAI
LEEWARD WATERS.

&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA







000
FXHW60 PHFO 231405
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
405 AM HST SAT MAY 23 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE SOUTH OF MAUI COUNTY THIS MORNING...
THEN ACROSS THE BIG ISLAND LATER TODAY AND TONIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. MODERATE NORTH TO
NORTHEAST WINDS WILL PREVAIL BEHIND THE FRONT FROM TODAY THROUGH
SUNDAY...WITH SHOWER ACTIVITY FOCUSED MAINLY ON WINDWARD COASTS
AND SLOPES. A CLOUD BAND MOVING OVER THE ISLANDS FROM THE NORTH
ON SUNDAY MAY ENHANCE THE WINDWARD SHOWERS SOMEWHAT. LIGHTER
NORTHEAST WINDS ARE EXPECTED FOR MONDAY...WITH LIGHT BACKGROUND
FLOW AND A RETURN TO A LAND AND SEA BREEZE PATTERN FORECAST FOR
TUESDAY THROUGH THURSDAY.

&&

.DISCUSSION...
AN INCREASINGLY DIFFUSE COLD FRONT LIES ACROSS MAUI COUNTY
CURRENTLY...WITH SHOWER ACTIVITY ALONG AND AHEAD OF THE FRONT
AFFECTING WINDWARD MAUI AND APPROACHING THE HAMAKUA COAST OF THE
BIG ISLAND. PERSISTENT MODERATE TO OCCASIONALLY HEAVY RAINS
ANCHORED ON THE NORTH/NORTHEAST FACING SLOPES REQUIRED SEVERAL
FLOOD ADVISORIES TO BE ISSUED DURING THE NIGHT...WITH SEVERAL
STREAM GAUGES ON MOLOKAI AND MAUI EARLIER SHOWING MODEST WATER
LEVEL RISES. DRIER NORTHERLY FLOW PREVAILS ACROSS OAHU AND KAUAI
BEHIND THE FRONT. SURFACE ANALYSIS DEPICTS THE AFOREMENTIONED
FRONT STRETCHING SW FROM A LOW CENTERED ABOUT 900 MILES NNE OF
PHNL...WITH A 1026 MB HIGH CENTERED ABOUT 1000 MILES NW OF KAUAI.
AN UNSEASONABLY DEEP TROUGH ALOFT IS LOCATED OVER THE CENTRAL
PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT OF THE SURFACE FRONT
SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN LATE MAY. MIMIC-TPW
SATELLITE IMAGERY DEPICTS A NARROW BAND OF ENHANCED MOISTURE ALONG
THE FRONT...WITH ESTIMATED PWATS UP TO 1.5 INCHES. THE 12Z LIHUE
SOUNDING REFLECTED THE DRIER AIRMASS BEHIND THE FRONT...WITH THE
INVERSION DOWN TO 5K FEET AND PWAT OF 0.99 INCHES. THERE HAS BEEN
LITTLE AIRMASS CHANGE DURING THE PAST 12 HOURS AT HILO AHEAD OF
THE FRONT...WITH THE INVERSION STILL AROUND 9K FEET AND PWAT OF
1.28 INCHES.

FOR TODAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING SOUTHWARD
FROM MAUI ACROSS THE BIG ISLAND. SHOWERS WILL MAINLY AFFECT
WINDWARD AREAS...ALTHOUGH THE DEEPER MOISTURE ALONG THE FRONT
WILL PROBABLY ALLOW SCATTERED SHOWERS TO DEVELOP ALONG THE KONA
COAST DURING THE AFTERNOON. DRIER NNE FLOW WILL PREVAIL ACROSS
KAUAI AND OAHU...WITH IMPROVING CONDITIONS SPREADING INTO MAUI
COUNTY DURING THE DAY. A SLIGHTLY DRIER AND COOLER AIR MASS HAS
SPREAD INTO THE WESTERN END OF THE STATE BEHIND THE FRONT...WITH
DEW POINTS HAVING ALREADY DROPPED INTO THE LOWER 60S. HIGH TEMPS
SHOULD BE A COUPLE OF DEGREES COOLER THIS WEEKEND THAN THEY HAVE
BEEN RECENTLY FOR MOST AREAS.

THE PARENT LOW OF THE FRONT WILL MOVE SOUTH AND WEAKEN THROUGH THE
WEEKEND...AS HIGH PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL
KEEP A RELATIVELY COOL MODERATE N/NE WIND FLOW OVER THE STATE
TONIGHT AND SUNDAY. SHALLOW BANDS OF MOISTURE ROTATING AROUND THE
LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH AND EAST FACING
SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH
THE PERIOD. GFS CONTINUES TO INDICATE THAT A WEAK BAND OF ENHANCED
MOISTURE WILL MOVE ACROSS THE STATE SUNDAY INTO SUNDAY EVENING.
LIGHT NE FLOW SHOULD HOLD THROUGH MONDAY...BUT THEN IS FORECAST TO
WEAKEN FURTHER TUESDAY THROUGH THURSDAY AS LOW PRESSURE LINGERS
FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO OUR NORTHWEST. THIS
WILL LIKELY ALLOW LAND AND SEA BREEZES TO DOMINATE THE LOCAL
WEATHER REGIME ONCE AGAIN....WITH AFTERNOON CLOUDS AND SHOWERS
ACROSS THE INTERIOR/LEEWARD AREAS OF THE ISLANDS. THE LOW SHOULD
FINALLY EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING A
WEAK HIGH PRESSURE RIDGE TO BUILD TO OUR NORTH...AND BRINGING
LIGHT TO MODERATE TRADES BACK ACROSS THE STATE.

&&

.AVIATION...
A WEAKENING COLD FRONT ACROSS MAUI COUNTY WILL SHIFT SOUTHEASTWARD
AND INTO THE BIG ISLAND THIS MORNING...AND PUSH SOUTH OF STATE
TONIGHT. TEMPORARY MVFR CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS
AS THE FRONT MOVES THROUGH...WITH IMPROVING CONDITIONS EXPECTED
BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS MOLOKAI
LANAI AND MAUI...AND THESE CONDITIONS SHOULD IMPROVE AROUND
DAYBREAK. AN AIRMET MAY BE NEEDED ACROSS THE BIG ISLAND LATER THIS
MORNING FOR MOUNTAIN OBSCURATION AS WELL.

&&

.MARINE...
THE FRIDAY EVENING ASCAT PASS FOUND AREAS OF 20 KT WINDS ACROSS
THE WESTERN HAWAIIAN COASTAL WATERS...BEHIND THE ADVANCING COLD
FRONT. A SMALL CRAFT ADVISORY /SCA/ REMAINS IN EFFECT FOR THE
LEEWARD KAUAI COASTAL WATERS THROUGH TODAY...WITH 25 KT WINDS
POSSIBLE MAINLY ACROSS THE KAULAKAHI CHANNEL. MODERATE TO FRESH
N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD THROUGH THE REMAINDER OF
THE COASTAL WATERS AROUND THE BIG ISLAND TODAY...AND PREVAIL
STATEWIDE TONIGHT AND SUNDAY. WINDS ARE FORECAST TO REMAIN BELOW
SCA LEVELS AT THIS POINT...BUT MAY COME CLOSE IN SOME AREAS
EXPOSED TO THE NNE WIND DIRECTION. WINDS WILL THEN WEAKEN ONCE
AGAIN MONDAY...BECOMING LIGHT WITH AFTERNOON SEABREEZES LIKELY
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF SOUTH SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP
SOUTH PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF
TO SOUTH FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO
REMAIN BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT
OVERLAPPING SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO
NEAR ADVISORY-LEVELS ALONG EXPOSED SOUTH FACING SHORES. A
MODERATE NNE SWELL IS EXPECTED TO ARRIVE ON SUNDAY AND LINGER
THROUGH MONDAY...BUT RELATIVELY SHORT SWELL PERIODS SHOULD RESULT
IN SURF WELL BELOW ADVISORY LEVELS ON NORTH FACING SHORES.
OTHERWISE...A COUPLE OF SMALL SWELLS FROM THE NNW AND WNW ARE
EXPECTED OVER THE WEEKEND AND EARLY NEXT WEEK...WITH RESULTANT
SURF WELL BELOW ADVISORY LEVELS. SEE THE LATEST OAHU SURF
DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON HST TODAY FOR BIG ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR KAUAI
LEEWARD WATERS.

&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA








000
FXHW60 PHFO 231405
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
405 AM HST SAT MAY 23 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE SOUTH OF MAUI COUNTY THIS MORNING...
THEN ACROSS THE BIG ISLAND LATER TODAY AND TONIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. MODERATE NORTH TO
NORTHEAST WINDS WILL PREVAIL BEHIND THE FRONT FROM TODAY THROUGH
SUNDAY...WITH SHOWER ACTIVITY FOCUSED MAINLY ON WINDWARD COASTS
AND SLOPES. A CLOUD BAND MOVING OVER THE ISLANDS FROM THE NORTH
ON SUNDAY MAY ENHANCE THE WINDWARD SHOWERS SOMEWHAT. LIGHTER
NORTHEAST WINDS ARE EXPECTED FOR MONDAY...WITH LIGHT BACKGROUND
FLOW AND A RETURN TO A LAND AND SEA BREEZE PATTERN FORECAST FOR
TUESDAY THROUGH THURSDAY.

&&

.DISCUSSION...
AN INCREASINGLY DIFFUSE COLD FRONT LIES ACROSS MAUI COUNTY
CURRENTLY...WITH SHOWER ACTIVITY ALONG AND AHEAD OF THE FRONT
AFFECTING WINDWARD MAUI AND APPROACHING THE HAMAKUA COAST OF THE
BIG ISLAND. PERSISTENT MODERATE TO OCCASIONALLY HEAVY RAINS
ANCHORED ON THE NORTH/NORTHEAST FACING SLOPES REQUIRED SEVERAL
FLOOD ADVISORIES TO BE ISSUED DURING THE NIGHT...WITH SEVERAL
STREAM GAUGES ON MOLOKAI AND MAUI EARLIER SHOWING MODEST WATER
LEVEL RISES. DRIER NORTHERLY FLOW PREVAILS ACROSS OAHU AND KAUAI
BEHIND THE FRONT. SURFACE ANALYSIS DEPICTS THE AFOREMENTIONED
FRONT STRETCHING SW FROM A LOW CENTERED ABOUT 900 MILES NNE OF
PHNL...WITH A 1026 MB HIGH CENTERED ABOUT 1000 MILES NW OF KAUAI.
AN UNSEASONABLY DEEP TROUGH ALOFT IS LOCATED OVER THE CENTRAL
PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT OF THE SURFACE FRONT
SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN LATE MAY. MIMIC-TPW
SATELLITE IMAGERY DEPICTS A NARROW BAND OF ENHANCED MOISTURE ALONG
THE FRONT...WITH ESTIMATED PWATS UP TO 1.5 INCHES. THE 12Z LIHUE
SOUNDING REFLECTED THE DRIER AIRMASS BEHIND THE FRONT...WITH THE
INVERSION DOWN TO 5K FEET AND PWAT OF 0.99 INCHES. THERE HAS BEEN
LITTLE AIRMASS CHANGE DURING THE PAST 12 HOURS AT HILO AHEAD OF
THE FRONT...WITH THE INVERSION STILL AROUND 9K FEET AND PWAT OF
1.28 INCHES.

FOR TODAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING SOUTHWARD
FROM MAUI ACROSS THE BIG ISLAND. SHOWERS WILL MAINLY AFFECT
WINDWARD AREAS...ALTHOUGH THE DEEPER MOISTURE ALONG THE FRONT
WILL PROBABLY ALLOW SCATTERED SHOWERS TO DEVELOP ALONG THE KONA
COAST DURING THE AFTERNOON. DRIER NNE FLOW WILL PREVAIL ACROSS
KAUAI AND OAHU...WITH IMPROVING CONDITIONS SPREADING INTO MAUI
COUNTY DURING THE DAY. A SLIGHTLY DRIER AND COOLER AIR MASS HAS
SPREAD INTO THE WESTERN END OF THE STATE BEHIND THE FRONT...WITH
DEW POINTS HAVING ALREADY DROPPED INTO THE LOWER 60S. HIGH TEMPS
SHOULD BE A COUPLE OF DEGREES COOLER THIS WEEKEND THAN THEY HAVE
BEEN RECENTLY FOR MOST AREAS.

THE PARENT LOW OF THE FRONT WILL MOVE SOUTH AND WEAKEN THROUGH THE
WEEKEND...AS HIGH PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL
KEEP A RELATIVELY COOL MODERATE N/NE WIND FLOW OVER THE STATE
TONIGHT AND SUNDAY. SHALLOW BANDS OF MOISTURE ROTATING AROUND THE
LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH AND EAST FACING
SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH
THE PERIOD. GFS CONTINUES TO INDICATE THAT A WEAK BAND OF ENHANCED
MOISTURE WILL MOVE ACROSS THE STATE SUNDAY INTO SUNDAY EVENING.
LIGHT NE FLOW SHOULD HOLD THROUGH MONDAY...BUT THEN IS FORECAST TO
WEAKEN FURTHER TUESDAY THROUGH THURSDAY AS LOW PRESSURE LINGERS
FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO OUR NORTHWEST. THIS
WILL LIKELY ALLOW LAND AND SEA BREEZES TO DOMINATE THE LOCAL
WEATHER REGIME ONCE AGAIN....WITH AFTERNOON CLOUDS AND SHOWERS
ACROSS THE INTERIOR/LEEWARD AREAS OF THE ISLANDS. THE LOW SHOULD
FINALLY EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING A
WEAK HIGH PRESSURE RIDGE TO BUILD TO OUR NORTH...AND BRINGING
LIGHT TO MODERATE TRADES BACK ACROSS THE STATE.

&&

.AVIATION...
A WEAKENING COLD FRONT ACROSS MAUI COUNTY WILL SHIFT SOUTHEASTWARD
AND INTO THE BIG ISLAND THIS MORNING...AND PUSH SOUTH OF STATE
TONIGHT. TEMPORARY MVFR CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS
AS THE FRONT MOVES THROUGH...WITH IMPROVING CONDITIONS EXPECTED
BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS MOLOKAI
LANAI AND MAUI...AND THESE CONDITIONS SHOULD IMPROVE AROUND
DAYBREAK. AN AIRMET MAY BE NEEDED ACROSS THE BIG ISLAND LATER THIS
MORNING FOR MOUNTAIN OBSCURATION AS WELL.

&&

.MARINE...
THE FRIDAY EVENING ASCAT PASS FOUND AREAS OF 20 KT WINDS ACROSS
THE WESTERN HAWAIIAN COASTAL WATERS...BEHIND THE ADVANCING COLD
FRONT. A SMALL CRAFT ADVISORY /SCA/ REMAINS IN EFFECT FOR THE
LEEWARD KAUAI COASTAL WATERS THROUGH TODAY...WITH 25 KT WINDS
POSSIBLE MAINLY ACROSS THE KAULAKAHI CHANNEL. MODERATE TO FRESH
N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD THROUGH THE REMAINDER OF
THE COASTAL WATERS AROUND THE BIG ISLAND TODAY...AND PREVAIL
STATEWIDE TONIGHT AND SUNDAY. WINDS ARE FORECAST TO REMAIN BELOW
SCA LEVELS AT THIS POINT...BUT MAY COME CLOSE IN SOME AREAS
EXPOSED TO THE NNE WIND DIRECTION. WINDS WILL THEN WEAKEN ONCE
AGAIN MONDAY...BECOMING LIGHT WITH AFTERNOON SEABREEZES LIKELY
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF SOUTH SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP
SOUTH PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF
TO SOUTH FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO
REMAIN BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT
OVERLAPPING SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO
NEAR ADVISORY-LEVELS ALONG EXPOSED SOUTH FACING SHORES. A
MODERATE NNE SWELL IS EXPECTED TO ARRIVE ON SUNDAY AND LINGER
THROUGH MONDAY...BUT RELATIVELY SHORT SWELL PERIODS SHOULD RESULT
IN SURF WELL BELOW ADVISORY LEVELS ON NORTH FACING SHORES.
OTHERWISE...A COUPLE OF SMALL SWELLS FROM THE NNW AND WNW ARE
EXPECTED OVER THE WEEKEND AND EARLY NEXT WEEK...WITH RESULTANT
SURF WELL BELOW ADVISORY LEVELS. SEE THE LATEST OAHU SURF
DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON HST TODAY FOR BIG ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR KAUAI
LEEWARD WATERS.

&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA







000
FXHW60 PHFO 231405
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
405 AM HST SAT MAY 23 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE SOUTH OF MAUI COUNTY THIS MORNING...
THEN ACROSS THE BIG ISLAND LATER TODAY AND TONIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. MODERATE NORTH TO
NORTHEAST WINDS WILL PREVAIL BEHIND THE FRONT FROM TODAY THROUGH
SUNDAY...WITH SHOWER ACTIVITY FOCUSED MAINLY ON WINDWARD COASTS
AND SLOPES. A CLOUD BAND MOVING OVER THE ISLANDS FROM THE NORTH
ON SUNDAY MAY ENHANCE THE WINDWARD SHOWERS SOMEWHAT. LIGHTER
NORTHEAST WINDS ARE EXPECTED FOR MONDAY...WITH LIGHT BACKGROUND
FLOW AND A RETURN TO A LAND AND SEA BREEZE PATTERN FORECAST FOR
TUESDAY THROUGH THURSDAY.

&&

.DISCUSSION...
AN INCREASINGLY DIFFUSE COLD FRONT LIES ACROSS MAUI COUNTY
CURRENTLY...WITH SHOWER ACTIVITY ALONG AND AHEAD OF THE FRONT
AFFECTING WINDWARD MAUI AND APPROACHING THE HAMAKUA COAST OF THE
BIG ISLAND. PERSISTENT MODERATE TO OCCASIONALLY HEAVY RAINS
ANCHORED ON THE NORTH/NORTHEAST FACING SLOPES REQUIRED SEVERAL
FLOOD ADVISORIES TO BE ISSUED DURING THE NIGHT...WITH SEVERAL
STREAM GAUGES ON MOLOKAI AND MAUI EARLIER SHOWING MODEST WATER
LEVEL RISES. DRIER NORTHERLY FLOW PREVAILS ACROSS OAHU AND KAUAI
BEHIND THE FRONT. SURFACE ANALYSIS DEPICTS THE AFOREMENTIONED
FRONT STRETCHING SW FROM A LOW CENTERED ABOUT 900 MILES NNE OF
PHNL...WITH A 1026 MB HIGH CENTERED ABOUT 1000 MILES NW OF KAUAI.
AN UNSEASONABLY DEEP TROUGH ALOFT IS LOCATED OVER THE CENTRAL
PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT OF THE SURFACE FRONT
SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN LATE MAY. MIMIC-TPW
SATELLITE IMAGERY DEPICTS A NARROW BAND OF ENHANCED MOISTURE ALONG
THE FRONT...WITH ESTIMATED PWATS UP TO 1.5 INCHES. THE 12Z LIHUE
SOUNDING REFLECTED THE DRIER AIRMASS BEHIND THE FRONT...WITH THE
INVERSION DOWN TO 5K FEET AND PWAT OF 0.99 INCHES. THERE HAS BEEN
LITTLE AIRMASS CHANGE DURING THE PAST 12 HOURS AT HILO AHEAD OF
THE FRONT...WITH THE INVERSION STILL AROUND 9K FEET AND PWAT OF
1.28 INCHES.

FOR TODAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING SOUTHWARD
FROM MAUI ACROSS THE BIG ISLAND. SHOWERS WILL MAINLY AFFECT
WINDWARD AREAS...ALTHOUGH THE DEEPER MOISTURE ALONG THE FRONT
WILL PROBABLY ALLOW SCATTERED SHOWERS TO DEVELOP ALONG THE KONA
COAST DURING THE AFTERNOON. DRIER NNE FLOW WILL PREVAIL ACROSS
KAUAI AND OAHU...WITH IMPROVING CONDITIONS SPREADING INTO MAUI
COUNTY DURING THE DAY. A SLIGHTLY DRIER AND COOLER AIR MASS HAS
SPREAD INTO THE WESTERN END OF THE STATE BEHIND THE FRONT...WITH
DEW POINTS HAVING ALREADY DROPPED INTO THE LOWER 60S. HIGH TEMPS
SHOULD BE A COUPLE OF DEGREES COOLER THIS WEEKEND THAN THEY HAVE
BEEN RECENTLY FOR MOST AREAS.

THE PARENT LOW OF THE FRONT WILL MOVE SOUTH AND WEAKEN THROUGH THE
WEEKEND...AS HIGH PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL
KEEP A RELATIVELY COOL MODERATE N/NE WIND FLOW OVER THE STATE
TONIGHT AND SUNDAY. SHALLOW BANDS OF MOISTURE ROTATING AROUND THE
LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH AND EAST FACING
SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH
THE PERIOD. GFS CONTINUES TO INDICATE THAT A WEAK BAND OF ENHANCED
MOISTURE WILL MOVE ACROSS THE STATE SUNDAY INTO SUNDAY EVENING.
LIGHT NE FLOW SHOULD HOLD THROUGH MONDAY...BUT THEN IS FORECAST TO
WEAKEN FURTHER TUESDAY THROUGH THURSDAY AS LOW PRESSURE LINGERS
FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO OUR NORTHWEST. THIS
WILL LIKELY ALLOW LAND AND SEA BREEZES TO DOMINATE THE LOCAL
WEATHER REGIME ONCE AGAIN....WITH AFTERNOON CLOUDS AND SHOWERS
ACROSS THE INTERIOR/LEEWARD AREAS OF THE ISLANDS. THE LOW SHOULD
FINALLY EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING A
WEAK HIGH PRESSURE RIDGE TO BUILD TO OUR NORTH...AND BRINGING
LIGHT TO MODERATE TRADES BACK ACROSS THE STATE.

&&

.AVIATION...
A WEAKENING COLD FRONT ACROSS MAUI COUNTY WILL SHIFT SOUTHEASTWARD
AND INTO THE BIG ISLAND THIS MORNING...AND PUSH SOUTH OF STATE
TONIGHT. TEMPORARY MVFR CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS
AS THE FRONT MOVES THROUGH...WITH IMPROVING CONDITIONS EXPECTED
BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS MOLOKAI
LANAI AND MAUI...AND THESE CONDITIONS SHOULD IMPROVE AROUND
DAYBREAK. AN AIRMET MAY BE NEEDED ACROSS THE BIG ISLAND LATER THIS
MORNING FOR MOUNTAIN OBSCURATION AS WELL.

&&

.MARINE...
THE FRIDAY EVENING ASCAT PASS FOUND AREAS OF 20 KT WINDS ACROSS
THE WESTERN HAWAIIAN COASTAL WATERS...BEHIND THE ADVANCING COLD
FRONT. A SMALL CRAFT ADVISORY /SCA/ REMAINS IN EFFECT FOR THE
LEEWARD KAUAI COASTAL WATERS THROUGH TODAY...WITH 25 KT WINDS
POSSIBLE MAINLY ACROSS THE KAULAKAHI CHANNEL. MODERATE TO FRESH
N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD THROUGH THE REMAINDER OF
THE COASTAL WATERS AROUND THE BIG ISLAND TODAY...AND PREVAIL
STATEWIDE TONIGHT AND SUNDAY. WINDS ARE FORECAST TO REMAIN BELOW
SCA LEVELS AT THIS POINT...BUT MAY COME CLOSE IN SOME AREAS
EXPOSED TO THE NNE WIND DIRECTION. WINDS WILL THEN WEAKEN ONCE
AGAIN MONDAY...BECOMING LIGHT WITH AFTERNOON SEABREEZES LIKELY
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF SOUTH SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP
SOUTH PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF
TO SOUTH FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO
REMAIN BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT
OVERLAPPING SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO
NEAR ADVISORY-LEVELS ALONG EXPOSED SOUTH FACING SHORES. A
MODERATE NNE SWELL IS EXPECTED TO ARRIVE ON SUNDAY AND LINGER
THROUGH MONDAY...BUT RELATIVELY SHORT SWELL PERIODS SHOULD RESULT
IN SURF WELL BELOW ADVISORY LEVELS ON NORTH FACING SHORES.
OTHERWISE...A COUPLE OF SMALL SWELLS FROM THE NNW AND WNW ARE
EXPECTED OVER THE WEEKEND AND EARLY NEXT WEEK...WITH RESULTANT
SURF WELL BELOW ADVISORY LEVELS. SEE THE LATEST OAHU SURF
DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON HST TODAY FOR BIG ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR KAUAI
LEEWARD WATERS.

&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA








000
FXHW60 PHFO 230905
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1105 PM HST FRI MAY 22 2015

.UPDATE...
WEST WINDS HAVE INCREASED TO LOW-END ADVISORY LEVELS ON THE BIG
ISLAND SUMMITS DURING THE EVENING...DUE TO THE MID LEVEL TROUGH
PASSING BY THE STATE TO OUR NORTH. HAVE ISSUED A WIND ADVISORY FOR
THE SUMMITS THROUGH NOON SATURDAY.

&&

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER MAUI COUNTY OVERNIGHT...AND THE
WINDWARD BIG ISLAND SATURDAY AND SATURDAY NIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...FOCUSING MOST
OF ITS ASSOCIATED MOISTURE ALONG WINDWARD SLOPES AND COASTS. AFTER
THE FRONT PASSES...LIGHT TO MODERATE NORTHEAST TO NORTH WINDS WILL
PREVAIL INTO EARLY NEXT WEEK...WITH BRIEF SHOWERS FAVORING
WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND MORNINGS.
HOWEVER...A CLOUD BAND MOVING OVER THE ISLANDS ON SUNDAY MAY BRING
A FEW EXTRA WINDWARD SHOWERS.

&&

.PREV DISCUSSION.../ISSUED 855 PM HST FRI MAY 22 2015/

A BAND OF LOW CLOUDS ACCOMPANIED BY SCATTERED SHOWERS MARKS A WEAK
COLD FRONT...WHICH LIES ACROSS OAHU AND MOLOKAI AS OF MID EVENING.
SOME ISOLATED HEAVY RAINS OCCURRED LATE THIS AFTERNOON OVER PARTS
OF OAHU...AND LOCALLY HEAVIER SHOWERS HAVE FIRED UP RECENTLY
ACROSS EASTERN OAHU AND MOLOKAI...REQUIRING FLOOD ADVISORIES TO BE
ISSUED. ELSEWHERE AROUND THE STATE...NORTHERLY FLOW PREVAILS
ACROSS KAUAI BEHIND THE FRONT...WITH LIGHT WINDS AND WIDELY
SCATTERED SHOWERS AROUND MAUI AND THE BIG ISLAND. SURFACE ANALYSIS
DEPICTS THE AFOREMENTIONED FRONT STRETCHING SW FROM A LOW CENTERED
ABOUT 900 MILES NNE OF PHNL...WITH A 1025 MB HIGH CENTERED ABOUT
1000 MILES NW OF KAUAI. AN UNSEASONABLY DEEP TROUGH ALOFT IS
LOCATED OVER THE CENTRAL PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT
OF THE SURFACE FRONT SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN
LATE MAY. MIMIC-TPW SATELLITE IMAGERY DEPICTS A NARROW BAND OF
SOMEWHAT ENHANCED MOISTURE ALONG THE FRONT...WITH ESTIMATED PWATS
UP TO 1.5 INCHES. THIS AGREES WELL WITH THE 00Z LIHUE SOUNDING...
WHICH FOUND A HIGH/WEAK INVERSION BASED NEAR 12K FEET AND PWAT OF
1.4 INCHES. THE 00Z HILO SOUNDING REFLECTED A DRIER AIRMASS AHEAD
OF THE FRONT...WITH THE INVERSION BASED NEAR 9500 FEET AND PWAT OF
1.19 INCHES.

OVERNIGHT AND SATURDAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING
SOUTHWARD THROUGH THE STATE. BUILDING N/NE FLOW FILTERING THROUGH
THE FRONT WILL FOCUS MOST OF THE SHOWER ACTIVITY ACROSS WINDWARD
AND MAUKA AREAS. LOCALIZED HEAVIER SHOWERS WILL REMAIN POSSIBLE
ALONG THE FRONT THROUGH AT LEAST THE REST OF THIS EVENING AND
POSSIBLY INTO LATE TONIGHT. WOULD EXPECT MOSTLY LIGHTER SHOWERS
ON SATURDAY AS LOW LEVEL CONVERGENCE ALONG THE FRONT WEAKENS.
HAVE UPDATED THE FORECAST TO BRING THE HIGH POPS FURTHER SOUTH AND
EAST ACROSS MOLOKAI AND WEST MAUI FOR THIS EVENING.

THE FRONT WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH DEW
POINTS DROPPING ABOUT 3-5 DEGREES F. THUS SLIGHTLY COOLER AND
DRIER WEATHER IS EXPECTED FOR THE SMALLER ISLANDS ON SATURDAY.

THE PARENT LOW OF THE FRONT WILL STALL FAR NNE OF THE STATE
OVERNIGHT...THEN MOVE S AND WEAKEN THROUGH THE WEEKEND...AS HIGH
PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL KEEP A RELATIVELY
COOL NE WIND FLOW OVER THE AREA. SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH
AND EAST FACING SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY
STABLE THROUGH THE PERIOD. GFS CONTINUES TO INDICATE THAT ONE WEAK
BAND OF ENHANCED MOISTURE WILL MOVE ACROSS THE STATE SUNDAY AND
SUNDAY NIGHT. NE FLOW WILL REMAIN LIGHT TO MODERATE THROUGH MONDAY...
BUT SHOULD THEN WEAKEN TOWARD THE MIDDLE OF NEXT WEEK AS LOW
PRESSURE LINGERS FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO
OUR NORTHWEST. THIS WILL LIKELY ALLOW LAND AND SEA BREEZES TO
DOMINATE THE ISLAND WIND/WEATHER ONCE AGAIN. THE LOW SHOULD FINALLY
EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING THE RETURN
OF LIGHT TO MODERATE TRADES.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL SHIFT SOUTHEAST THROUGH MAUI COUNTY
TONIGHT AND INTO THE BIG ISLAND ON SATURDAY. TEMPORARY MVFR
CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS AS THE FRONT PUSHES
THROUGH...WITH IMPROVING CONDITIONS EXPECTED BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS KAUAI
OAHU MOLOKAI AND MAUI. CONDITIONS SHOULD IMPROVE LATER TONIGHT
ACROSS KAUAI AND OAHU. THE AIRMET MAY NEED TO BE EXPANDED TO INCLUDE
LANAI LATER THIS EVENING...AND POSSIBLY PORTIONS OF THE BIG ISLAND
SATURDAY MORNING.

&&

.MARINE...
NORTHERLY WINDS INCREASED TO 19 KT LATE FRIDAY AFTERNOON AT PHBK...
AND A SMALL CRAFT ADVISORY /SCA/ IS IN EFFECT FOR THE ADJACENT
LEEWARD KAUAI COASTAL WATERS THROUGH SATURDAY. WILL KEEP AN EYE ON
OTHER AREAS OVERNIGHT TO SEE IF 25 KT WINDS MAY DEVELOP AS THE
FRONT MOVES THROUGH...BUT CURRENT FORECASTS SHOW WINDS AROUND 20
KT AT MOST. MODERATE N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD
ACROSS THE STATE OVERNIGHT AND SATURDAY...AND PREVAIL STATEWIDE
SATURDAY NIGHT AND SUNDAY. WINDS WILL THEN WEAKEN ONCE AGAIN
MONDAY...BECOMING LIGHT WITH POSSIBLE AFTERNOON SEABREEZES
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN
BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT OVERLAPPING
SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR ADVISORY-
LEVELS ALONG EXPOSED S FACING SHORES. A MODERATE NNE SWELL IS
EXPECTED TO ARRIVE ON SUNDAY AND LINGER THROUGH MONDAY...BUT
RELATIVELY SHORT SWELL PERIODS SHOULD RESULTING SURF WELL BELOW
ADVISORY LEVELS ON NORTH FACING SHORES. OTHERWISE...A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.
SEE THE LATEST OAHU SURF DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON HST SATURDAY FOR BIG ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI LEEWARD
WATERS.


&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA







000
FXHW60 PHFO 230905
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1105 PM HST FRI MAY 22 2015

.UPDATE...
WEST WINDS HAVE INCREASED TO LOW-END ADVISORY LEVELS ON THE BIG
ISLAND SUMMITS DURING THE EVENING...DUE TO THE MID LEVEL TROUGH
PASSING BY THE STATE TO OUR NORTH. HAVE ISSUED A WIND ADVISORY FOR
THE SUMMITS THROUGH NOON SATURDAY.

&&

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER MAUI COUNTY OVERNIGHT...AND THE
WINDWARD BIG ISLAND SATURDAY AND SATURDAY NIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...FOCUSING MOST
OF ITS ASSOCIATED MOISTURE ALONG WINDWARD SLOPES AND COASTS. AFTER
THE FRONT PASSES...LIGHT TO MODERATE NORTHEAST TO NORTH WINDS WILL
PREVAIL INTO EARLY NEXT WEEK...WITH BRIEF SHOWERS FAVORING
WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND MORNINGS.
HOWEVER...A CLOUD BAND MOVING OVER THE ISLANDS ON SUNDAY MAY BRING
A FEW EXTRA WINDWARD SHOWERS.

&&

.PREV DISCUSSION.../ISSUED 855 PM HST FRI MAY 22 2015/

A BAND OF LOW CLOUDS ACCOMPANIED BY SCATTERED SHOWERS MARKS A WEAK
COLD FRONT...WHICH LIES ACROSS OAHU AND MOLOKAI AS OF MID EVENING.
SOME ISOLATED HEAVY RAINS OCCURRED LATE THIS AFTERNOON OVER PARTS
OF OAHU...AND LOCALLY HEAVIER SHOWERS HAVE FIRED UP RECENTLY
ACROSS EASTERN OAHU AND MOLOKAI...REQUIRING FLOOD ADVISORIES TO BE
ISSUED. ELSEWHERE AROUND THE STATE...NORTHERLY FLOW PREVAILS
ACROSS KAUAI BEHIND THE FRONT...WITH LIGHT WINDS AND WIDELY
SCATTERED SHOWERS AROUND MAUI AND THE BIG ISLAND. SURFACE ANALYSIS
DEPICTS THE AFOREMENTIONED FRONT STRETCHING SW FROM A LOW CENTERED
ABOUT 900 MILES NNE OF PHNL...WITH A 1025 MB HIGH CENTERED ABOUT
1000 MILES NW OF KAUAI. AN UNSEASONABLY DEEP TROUGH ALOFT IS
LOCATED OVER THE CENTRAL PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT
OF THE SURFACE FRONT SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN
LATE MAY. MIMIC-TPW SATELLITE IMAGERY DEPICTS A NARROW BAND OF
SOMEWHAT ENHANCED MOISTURE ALONG THE FRONT...WITH ESTIMATED PWATS
UP TO 1.5 INCHES. THIS AGREES WELL WITH THE 00Z LIHUE SOUNDING...
WHICH FOUND A HIGH/WEAK INVERSION BASED NEAR 12K FEET AND PWAT OF
1.4 INCHES. THE 00Z HILO SOUNDING REFLECTED A DRIER AIRMASS AHEAD
OF THE FRONT...WITH THE INVERSION BASED NEAR 9500 FEET AND PWAT OF
1.19 INCHES.

OVERNIGHT AND SATURDAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING
SOUTHWARD THROUGH THE STATE. BUILDING N/NE FLOW FILTERING THROUGH
THE FRONT WILL FOCUS MOST OF THE SHOWER ACTIVITY ACROSS WINDWARD
AND MAUKA AREAS. LOCALIZED HEAVIER SHOWERS WILL REMAIN POSSIBLE
ALONG THE FRONT THROUGH AT LEAST THE REST OF THIS EVENING AND
POSSIBLY INTO LATE TONIGHT. WOULD EXPECT MOSTLY LIGHTER SHOWERS
ON SATURDAY AS LOW LEVEL CONVERGENCE ALONG THE FRONT WEAKENS.
HAVE UPDATED THE FORECAST TO BRING THE HIGH POPS FURTHER SOUTH AND
EAST ACROSS MOLOKAI AND WEST MAUI FOR THIS EVENING.

THE FRONT WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH DEW
POINTS DROPPING ABOUT 3-5 DEGREES F. THUS SLIGHTLY COOLER AND
DRIER WEATHER IS EXPECTED FOR THE SMALLER ISLANDS ON SATURDAY.

THE PARENT LOW OF THE FRONT WILL STALL FAR NNE OF THE STATE
OVERNIGHT...THEN MOVE S AND WEAKEN THROUGH THE WEEKEND...AS HIGH
PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL KEEP A RELATIVELY
COOL NE WIND FLOW OVER THE AREA. SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH
AND EAST FACING SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY
STABLE THROUGH THE PERIOD. GFS CONTINUES TO INDICATE THAT ONE WEAK
BAND OF ENHANCED MOISTURE WILL MOVE ACROSS THE STATE SUNDAY AND
SUNDAY NIGHT. NE FLOW WILL REMAIN LIGHT TO MODERATE THROUGH MONDAY...
BUT SHOULD THEN WEAKEN TOWARD THE MIDDLE OF NEXT WEEK AS LOW
PRESSURE LINGERS FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO
OUR NORTHWEST. THIS WILL LIKELY ALLOW LAND AND SEA BREEZES TO
DOMINATE THE ISLAND WIND/WEATHER ONCE AGAIN. THE LOW SHOULD FINALLY
EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING THE RETURN
OF LIGHT TO MODERATE TRADES.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL SHIFT SOUTHEAST THROUGH MAUI COUNTY
TONIGHT AND INTO THE BIG ISLAND ON SATURDAY. TEMPORARY MVFR
CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS AS THE FRONT PUSHES
THROUGH...WITH IMPROVING CONDITIONS EXPECTED BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS KAUAI
OAHU MOLOKAI AND MAUI. CONDITIONS SHOULD IMPROVE LATER TONIGHT
ACROSS KAUAI AND OAHU. THE AIRMET MAY NEED TO BE EXPANDED TO INCLUDE
LANAI LATER THIS EVENING...AND POSSIBLY PORTIONS OF THE BIG ISLAND
SATURDAY MORNING.

&&

.MARINE...
NORTHERLY WINDS INCREASED TO 19 KT LATE FRIDAY AFTERNOON AT PHBK...
AND A SMALL CRAFT ADVISORY /SCA/ IS IN EFFECT FOR THE ADJACENT
LEEWARD KAUAI COASTAL WATERS THROUGH SATURDAY. WILL KEEP AN EYE ON
OTHER AREAS OVERNIGHT TO SEE IF 25 KT WINDS MAY DEVELOP AS THE
FRONT MOVES THROUGH...BUT CURRENT FORECASTS SHOW WINDS AROUND 20
KT AT MOST. MODERATE N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD
ACROSS THE STATE OVERNIGHT AND SATURDAY...AND PREVAIL STATEWIDE
SATURDAY NIGHT AND SUNDAY. WINDS WILL THEN WEAKEN ONCE AGAIN
MONDAY...BECOMING LIGHT WITH POSSIBLE AFTERNOON SEABREEZES
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN
BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT OVERLAPPING
SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR ADVISORY-
LEVELS ALONG EXPOSED S FACING SHORES. A MODERATE NNE SWELL IS
EXPECTED TO ARRIVE ON SUNDAY AND LINGER THROUGH MONDAY...BUT
RELATIVELY SHORT SWELL PERIODS SHOULD RESULTING SURF WELL BELOW
ADVISORY LEVELS ON NORTH FACING SHORES. OTHERWISE...A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.
SEE THE LATEST OAHU SURF DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON HST SATURDAY FOR BIG ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI LEEWARD
WATERS.


&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA








000
FXHW60 PHFO 230905
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1105 PM HST FRI MAY 22 2015

.UPDATE...
WEST WINDS HAVE INCREASED TO LOW-END ADVISORY LEVELS ON THE BIG
ISLAND SUMMITS DURING THE EVENING...DUE TO THE MID LEVEL TROUGH
PASSING BY THE STATE TO OUR NORTH. HAVE ISSUED A WIND ADVISORY FOR
THE SUMMITS THROUGH NOON SATURDAY.

&&

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER MAUI COUNTY OVERNIGHT...AND THE
WINDWARD BIG ISLAND SATURDAY AND SATURDAY NIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...FOCUSING MOST
OF ITS ASSOCIATED MOISTURE ALONG WINDWARD SLOPES AND COASTS. AFTER
THE FRONT PASSES...LIGHT TO MODERATE NORTHEAST TO NORTH WINDS WILL
PREVAIL INTO EARLY NEXT WEEK...WITH BRIEF SHOWERS FAVORING
WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND MORNINGS.
HOWEVER...A CLOUD BAND MOVING OVER THE ISLANDS ON SUNDAY MAY BRING
A FEW EXTRA WINDWARD SHOWERS.

&&

.PREV DISCUSSION.../ISSUED 855 PM HST FRI MAY 22 2015/

A BAND OF LOW CLOUDS ACCOMPANIED BY SCATTERED SHOWERS MARKS A WEAK
COLD FRONT...WHICH LIES ACROSS OAHU AND MOLOKAI AS OF MID EVENING.
SOME ISOLATED HEAVY RAINS OCCURRED LATE THIS AFTERNOON OVER PARTS
OF OAHU...AND LOCALLY HEAVIER SHOWERS HAVE FIRED UP RECENTLY
ACROSS EASTERN OAHU AND MOLOKAI...REQUIRING FLOOD ADVISORIES TO BE
ISSUED. ELSEWHERE AROUND THE STATE...NORTHERLY FLOW PREVAILS
ACROSS KAUAI BEHIND THE FRONT...WITH LIGHT WINDS AND WIDELY
SCATTERED SHOWERS AROUND MAUI AND THE BIG ISLAND. SURFACE ANALYSIS
DEPICTS THE AFOREMENTIONED FRONT STRETCHING SW FROM A LOW CENTERED
ABOUT 900 MILES NNE OF PHNL...WITH A 1025 MB HIGH CENTERED ABOUT
1000 MILES NW OF KAUAI. AN UNSEASONABLY DEEP TROUGH ALOFT IS
LOCATED OVER THE CENTRAL PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT
OF THE SURFACE FRONT SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN
LATE MAY. MIMIC-TPW SATELLITE IMAGERY DEPICTS A NARROW BAND OF
SOMEWHAT ENHANCED MOISTURE ALONG THE FRONT...WITH ESTIMATED PWATS
UP TO 1.5 INCHES. THIS AGREES WELL WITH THE 00Z LIHUE SOUNDING...
WHICH FOUND A HIGH/WEAK INVERSION BASED NEAR 12K FEET AND PWAT OF
1.4 INCHES. THE 00Z HILO SOUNDING REFLECTED A DRIER AIRMASS AHEAD
OF THE FRONT...WITH THE INVERSION BASED NEAR 9500 FEET AND PWAT OF
1.19 INCHES.

OVERNIGHT AND SATURDAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING
SOUTHWARD THROUGH THE STATE. BUILDING N/NE FLOW FILTERING THROUGH
THE FRONT WILL FOCUS MOST OF THE SHOWER ACTIVITY ACROSS WINDWARD
AND MAUKA AREAS. LOCALIZED HEAVIER SHOWERS WILL REMAIN POSSIBLE
ALONG THE FRONT THROUGH AT LEAST THE REST OF THIS EVENING AND
POSSIBLY INTO LATE TONIGHT. WOULD EXPECT MOSTLY LIGHTER SHOWERS
ON SATURDAY AS LOW LEVEL CONVERGENCE ALONG THE FRONT WEAKENS.
HAVE UPDATED THE FORECAST TO BRING THE HIGH POPS FURTHER SOUTH AND
EAST ACROSS MOLOKAI AND WEST MAUI FOR THIS EVENING.

THE FRONT WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH DEW
POINTS DROPPING ABOUT 3-5 DEGREES F. THUS SLIGHTLY COOLER AND
DRIER WEATHER IS EXPECTED FOR THE SMALLER ISLANDS ON SATURDAY.

THE PARENT LOW OF THE FRONT WILL STALL FAR NNE OF THE STATE
OVERNIGHT...THEN MOVE S AND WEAKEN THROUGH THE WEEKEND...AS HIGH
PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL KEEP A RELATIVELY
COOL NE WIND FLOW OVER THE AREA. SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH
AND EAST FACING SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY
STABLE THROUGH THE PERIOD. GFS CONTINUES TO INDICATE THAT ONE WEAK
BAND OF ENHANCED MOISTURE WILL MOVE ACROSS THE STATE SUNDAY AND
SUNDAY NIGHT. NE FLOW WILL REMAIN LIGHT TO MODERATE THROUGH MONDAY...
BUT SHOULD THEN WEAKEN TOWARD THE MIDDLE OF NEXT WEEK AS LOW
PRESSURE LINGERS FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO
OUR NORTHWEST. THIS WILL LIKELY ALLOW LAND AND SEA BREEZES TO
DOMINATE THE ISLAND WIND/WEATHER ONCE AGAIN. THE LOW SHOULD FINALLY
EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING THE RETURN
OF LIGHT TO MODERATE TRADES.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL SHIFT SOUTHEAST THROUGH MAUI COUNTY
TONIGHT AND INTO THE BIG ISLAND ON SATURDAY. TEMPORARY MVFR
CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS AS THE FRONT PUSHES
THROUGH...WITH IMPROVING CONDITIONS EXPECTED BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS KAUAI
OAHU MOLOKAI AND MAUI. CONDITIONS SHOULD IMPROVE LATER TONIGHT
ACROSS KAUAI AND OAHU. THE AIRMET MAY NEED TO BE EXPANDED TO INCLUDE
LANAI LATER THIS EVENING...AND POSSIBLY PORTIONS OF THE BIG ISLAND
SATURDAY MORNING.

&&

.MARINE...
NORTHERLY WINDS INCREASED TO 19 KT LATE FRIDAY AFTERNOON AT PHBK...
AND A SMALL CRAFT ADVISORY /SCA/ IS IN EFFECT FOR THE ADJACENT
LEEWARD KAUAI COASTAL WATERS THROUGH SATURDAY. WILL KEEP AN EYE ON
OTHER AREAS OVERNIGHT TO SEE IF 25 KT WINDS MAY DEVELOP AS THE
FRONT MOVES THROUGH...BUT CURRENT FORECASTS SHOW WINDS AROUND 20
KT AT MOST. MODERATE N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD
ACROSS THE STATE OVERNIGHT AND SATURDAY...AND PREVAIL STATEWIDE
SATURDAY NIGHT AND SUNDAY. WINDS WILL THEN WEAKEN ONCE AGAIN
MONDAY...BECOMING LIGHT WITH POSSIBLE AFTERNOON SEABREEZES
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN
BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT OVERLAPPING
SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR ADVISORY-
LEVELS ALONG EXPOSED S FACING SHORES. A MODERATE NNE SWELL IS
EXPECTED TO ARRIVE ON SUNDAY AND LINGER THROUGH MONDAY...BUT
RELATIVELY SHORT SWELL PERIODS SHOULD RESULTING SURF WELL BELOW
ADVISORY LEVELS ON NORTH FACING SHORES. OTHERWISE...A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.
SEE THE LATEST OAHU SURF DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON HST SATURDAY FOR BIG ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI LEEWARD
WATERS.


&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA







000
FXHW60 PHFO 230905
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1105 PM HST FRI MAY 22 2015

.UPDATE...
WEST WINDS HAVE INCREASED TO LOW-END ADVISORY LEVELS ON THE BIG
ISLAND SUMMITS DURING THE EVENING...DUE TO THE MID LEVEL TROUGH
PASSING BY THE STATE TO OUR NORTH. HAVE ISSUED A WIND ADVISORY FOR
THE SUMMITS THROUGH NOON SATURDAY.

&&

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER MAUI COUNTY OVERNIGHT...AND THE
WINDWARD BIG ISLAND SATURDAY AND SATURDAY NIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...FOCUSING MOST
OF ITS ASSOCIATED MOISTURE ALONG WINDWARD SLOPES AND COASTS. AFTER
THE FRONT PASSES...LIGHT TO MODERATE NORTHEAST TO NORTH WINDS WILL
PREVAIL INTO EARLY NEXT WEEK...WITH BRIEF SHOWERS FAVORING
WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND MORNINGS.
HOWEVER...A CLOUD BAND MOVING OVER THE ISLANDS ON SUNDAY MAY BRING
A FEW EXTRA WINDWARD SHOWERS.

&&

.PREV DISCUSSION.../ISSUED 855 PM HST FRI MAY 22 2015/

A BAND OF LOW CLOUDS ACCOMPANIED BY SCATTERED SHOWERS MARKS A WEAK
COLD FRONT...WHICH LIES ACROSS OAHU AND MOLOKAI AS OF MID EVENING.
SOME ISOLATED HEAVY RAINS OCCURRED LATE THIS AFTERNOON OVER PARTS
OF OAHU...AND LOCALLY HEAVIER SHOWERS HAVE FIRED UP RECENTLY
ACROSS EASTERN OAHU AND MOLOKAI...REQUIRING FLOOD ADVISORIES TO BE
ISSUED. ELSEWHERE AROUND THE STATE...NORTHERLY FLOW PREVAILS
ACROSS KAUAI BEHIND THE FRONT...WITH LIGHT WINDS AND WIDELY
SCATTERED SHOWERS AROUND MAUI AND THE BIG ISLAND. SURFACE ANALYSIS
DEPICTS THE AFOREMENTIONED FRONT STRETCHING SW FROM A LOW CENTERED
ABOUT 900 MILES NNE OF PHNL...WITH A 1025 MB HIGH CENTERED ABOUT
1000 MILES NW OF KAUAI. AN UNSEASONABLY DEEP TROUGH ALOFT IS
LOCATED OVER THE CENTRAL PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT
OF THE SURFACE FRONT SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN
LATE MAY. MIMIC-TPW SATELLITE IMAGERY DEPICTS A NARROW BAND OF
SOMEWHAT ENHANCED MOISTURE ALONG THE FRONT...WITH ESTIMATED PWATS
UP TO 1.5 INCHES. THIS AGREES WELL WITH THE 00Z LIHUE SOUNDING...
WHICH FOUND A HIGH/WEAK INVERSION BASED NEAR 12K FEET AND PWAT OF
1.4 INCHES. THE 00Z HILO SOUNDING REFLECTED A DRIER AIRMASS AHEAD
OF THE FRONT...WITH THE INVERSION BASED NEAR 9500 FEET AND PWAT OF
1.19 INCHES.

OVERNIGHT AND SATURDAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING
SOUTHWARD THROUGH THE STATE. BUILDING N/NE FLOW FILTERING THROUGH
THE FRONT WILL FOCUS MOST OF THE SHOWER ACTIVITY ACROSS WINDWARD
AND MAUKA AREAS. LOCALIZED HEAVIER SHOWERS WILL REMAIN POSSIBLE
ALONG THE FRONT THROUGH AT LEAST THE REST OF THIS EVENING AND
POSSIBLY INTO LATE TONIGHT. WOULD EXPECT MOSTLY LIGHTER SHOWERS
ON SATURDAY AS LOW LEVEL CONVERGENCE ALONG THE FRONT WEAKENS.
HAVE UPDATED THE FORECAST TO BRING THE HIGH POPS FURTHER SOUTH AND
EAST ACROSS MOLOKAI AND WEST MAUI FOR THIS EVENING.

THE FRONT WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH DEW
POINTS DROPPING ABOUT 3-5 DEGREES F. THUS SLIGHTLY COOLER AND
DRIER WEATHER IS EXPECTED FOR THE SMALLER ISLANDS ON SATURDAY.

THE PARENT LOW OF THE FRONT WILL STALL FAR NNE OF THE STATE
OVERNIGHT...THEN MOVE S AND WEAKEN THROUGH THE WEEKEND...AS HIGH
PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL KEEP A RELATIVELY
COOL NE WIND FLOW OVER THE AREA. SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH
AND EAST FACING SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY
STABLE THROUGH THE PERIOD. GFS CONTINUES TO INDICATE THAT ONE WEAK
BAND OF ENHANCED MOISTURE WILL MOVE ACROSS THE STATE SUNDAY AND
SUNDAY NIGHT. NE FLOW WILL REMAIN LIGHT TO MODERATE THROUGH MONDAY...
BUT SHOULD THEN WEAKEN TOWARD THE MIDDLE OF NEXT WEEK AS LOW
PRESSURE LINGERS FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO
OUR NORTHWEST. THIS WILL LIKELY ALLOW LAND AND SEA BREEZES TO
DOMINATE THE ISLAND WIND/WEATHER ONCE AGAIN. THE LOW SHOULD FINALLY
EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING THE RETURN
OF LIGHT TO MODERATE TRADES.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL SHIFT SOUTHEAST THROUGH MAUI COUNTY
TONIGHT AND INTO THE BIG ISLAND ON SATURDAY. TEMPORARY MVFR
CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS AS THE FRONT PUSHES
THROUGH...WITH IMPROVING CONDITIONS EXPECTED BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS KAUAI
OAHU MOLOKAI AND MAUI. CONDITIONS SHOULD IMPROVE LATER TONIGHT
ACROSS KAUAI AND OAHU. THE AIRMET MAY NEED TO BE EXPANDED TO INCLUDE
LANAI LATER THIS EVENING...AND POSSIBLY PORTIONS OF THE BIG ISLAND
SATURDAY MORNING.

&&

.MARINE...
NORTHERLY WINDS INCREASED TO 19 KT LATE FRIDAY AFTERNOON AT PHBK...
AND A SMALL CRAFT ADVISORY /SCA/ IS IN EFFECT FOR THE ADJACENT
LEEWARD KAUAI COASTAL WATERS THROUGH SATURDAY. WILL KEEP AN EYE ON
OTHER AREAS OVERNIGHT TO SEE IF 25 KT WINDS MAY DEVELOP AS THE
FRONT MOVES THROUGH...BUT CURRENT FORECASTS SHOW WINDS AROUND 20
KT AT MOST. MODERATE N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD
ACROSS THE STATE OVERNIGHT AND SATURDAY...AND PREVAIL STATEWIDE
SATURDAY NIGHT AND SUNDAY. WINDS WILL THEN WEAKEN ONCE AGAIN
MONDAY...BECOMING LIGHT WITH POSSIBLE AFTERNOON SEABREEZES
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN
BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT OVERLAPPING
SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR ADVISORY-
LEVELS ALONG EXPOSED S FACING SHORES. A MODERATE NNE SWELL IS
EXPECTED TO ARRIVE ON SUNDAY AND LINGER THROUGH MONDAY...BUT
RELATIVELY SHORT SWELL PERIODS SHOULD RESULTING SURF WELL BELOW
ADVISORY LEVELS ON NORTH FACING SHORES. OTHERWISE...A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.
SEE THE LATEST OAHU SURF DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON HST SATURDAY FOR BIG ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI LEEWARD
WATERS.


&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA








000
FXHW60 PHFO 230655
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
855 PM HST FRI MAY 22 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER MAUI COUNTY OVERNIGHT...AND THE
WINDWARD BIG ISLAND SATURDAY AND SATURDAY NIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...FOCUSING MOST
OF ITS ASSOCIATED MOISTURE ALONG WINDWARD SLOPES AND COASTS. AFTER
THE FRONT PASSES...LIGHT TO MODERATE NORTHEAST TO NORTH WINDS WILL
PREVAIL INTO EARLY NEXT WEEK...WITH BRIEF SHOWERS FAVORING
WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND MORNINGS.
HOWEVER...A CLOUD BAND MOVING OVER THE ISLANDS ON SUNDAY MAY BRING
A FEW EXTRA WINDWARD SHOWERS.

&&

.DISCUSSION...
A BAND OF LOW CLOUDS ACCOMPANIED BY SCATTERED SHOWERS MARKS A WEAK
COLD FRONT...WHICH LIES ACROSS OAHU AND MOLOKAI AS OF MID EVENING.
SOME ISOLATED HEAVY RAINS OCCURRED LATE THIS AFTERNOON OVER PARTS
OF OAHU...AND LOCALLY HEAVIER SHOWERS HAVE FIRED UP RECENTLY
ACROSS EASTERN OAHU AND MOLOKAI...REQUIRING FLOOD ADVISORIES TO BE
ISSUED. ELSEWHERE AROUND THE STATE...NORTHERLY FLOW PREVAILS
ACROSS KAUAI BEHIND THE FRONT...WITH LIGHT WINDS AND WIDELY
SCATTERED SHOWERS AROUND MAUI AND THE BIG ISLAND. SURFACE ANALYSIS
DEPICTS THE AFOREMENTIONED FRONT STRETCHING SW FROM A LOW CENTERED
ABOUT 900 MILES NNE OF PHNL...WITH A 1025 MB HIGH CENTERED ABOUT
1000 MILES NW OF KAUAI. AN UNSEASONABLY DEEP TROUGH ALOFT IS
LOCATED OVER THE CENTRAL PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT
OF THE SURFACE FRONT SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN
LATE MAY. MIMIC-TPW SATELLITE IMAGERY DEPICTS A NARROW BAND OF
SOMEWHAT ENHANCED MOISTURE ALONG THE FRONT...WITH ESTIMATED PWATS
UP TO 1.5 INCHES. THIS AGREES WELL WITH THE 00Z LIHUE SOUNDING...
WHICH FOUND A HIGH/WEAK INVERSION BASED NEAR 12K FEET AND PWAT OF
1.4 INCHES. THE 00Z HILO SOUNDING REFLECTED A DRIER AIRMASS AHEAD
OF THE FRONT...WITH THE INVERSION BASED NEAR 9500 FEET AND PWAT OF
1.19 INCHES.

OVERNIGHT AND SATURDAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING
SOUTHWARD THROUGH THE STATE. BUILDING N/NE FLOW FILTERING THROUGH
THE FRONT WILL FOCUS MOST OF THE SHOWER ACTIVITY ACROSS WINDWARD
AND MAUKA AREAS. LOCALIZED HEAVIER SHOWERS WILL REMAIN POSSIBLE
ALONG THE FRONT THROUGH AT LEAST THE REST OF THIS EVENING AND
POSSIBLY INTO LATE TONIGHT. WOULD EXPECT MOSTLY LIGHTER SHOWERS
ON SATURDAY AS LOW LEVEL CONVERGENCE ALONG THE FRONT WEAKENS.
HAVE UPDATED THE FORECAST TO BRING THE HIGH POPS FURTHER SOUTH AND
EAST ACROSS MOLOKAI AND WEST MAUI FOR THIS EVENING.

THE FRONT WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH DEW
POINTS DROPPING ABOUT 3-5 DEGREES F. THUS SLIGHTLY COOLER AND
DRIER WEATHER IS EXPECTED FOR THE SMALLER ISLANDS ON SATURDAY.

THE PARENT LOW OF THE FRONT WILL STALL FAR NNE OF THE STATE
OVERNIGHT...THEN MOVE S AND WEAKEN THROUGH THE WEEKEND...AS HIGH
PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL KEEP A RELATIVELY
COOL NE WIND FLOW OVER THE AREA. SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH
AND EAST FACING SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY
STABLE THROUGH THE PERIOD. GFS CONTINUES TO INDICATE THAT ONE WEAK
BAND OF ENHANCED MOISTURE WILL MOVE ACROSS THE STATE SUNDAY AND
SUNDAY NIGHT. NE FLOW WILL REMAIN LIGHT TO MODERATE THROUGH MONDAY...
BUT SHOULD THEN WEAKEN TOWARD THE MIDDLE OF NEXT WEEK AS LOW
PRESSURE LINGERS FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO
OUR NORTHWEST. THIS WILL LIKELY ALLOW LAND AND SEA BREEZES TO
DOMINATE THE ISLAND WIND/WEATHER ONCE AGAIN. THE LOW SHOULD FINALLY
EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING THE RETURN
OF LIGHT TO MODERATE TRADES.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL SHIFT SOUTHEAST THROUGH MAUI COUNTY
TONIGHT AND INTO THE BIG ISLAND ON SATURDAY. TEMPORARY MVFR
CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS AS THE FRONT PUSHES
THROUGH...WITH IMPROVING CONDITIONS EXPECTED BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS KAUAI
OAHU MOLOKAI AND MAUI. CONDITIONS SHOULD IMPROVE LATER TONIGHT
ACROSS KAUAI AND OAHU. THE AIRMET MAY NEED TO BE EXPANDED TO INCLUDE
LANAI LATER THIS EVENING...AND POSSIBLY PORTIONS OF THE BIG ISLAND
SATURDAY MORNING.

&&

.MARINE...
NORTHERLY WINDS INCREASED TO 19 KT LATE FRIDAY AFTERNOON AT PHBK...
AND A SMALL CRAFT ADVISORY /SCA/ IS IN EFFECT FOR THE ADJACENT
LEEWARD KAUAI COASTAL WATERS THROUGH SATURDAY. WILL KEEP AN EYE ON
OTHER AREAS OVERNIGHT TO SEE IF 25 KT WINDS MAY DEVELOP AS THE
FRONT MOVES THROUGH...BUT CURRENT FORECASTS SHOW WINDS AROUND 20
KT AT MOST. MODERATE N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD
ACROSS THE STATE OVERNIGHT AND SATURDAY...AND PREVAIL STATEWIDE
SATURDAY NIGHT AND SUNDAY. WINDS WILL THEN WEAKEN ONCE AGAIN
MONDAY...BECOMING LIGHT WITH POSSIBLE AFTERNOON SEABREEZES
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN
BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT OVERLAPPING
SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR ADVISORY-
LEVELS ALONG EXPOSED S FACING SHORES. A MODERATE NNE SWELL IS
EXPECTED TO ARRIVE ON SUNDAY AND LINGER THROUGH MONDAY...BUT
RELATIVELY SHORT SWELL PERIODS SHOULD RESULTING SURF WELL BELOW
ADVISORY LEVELS ON NORTH FACING SHORES. OTHERWISE...A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.
SEE THE LATEST OAHU SURF DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI LEEWARD
WATERS.

&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA










000
FXHW60 PHFO 230655
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
855 PM HST FRI MAY 22 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER MAUI COUNTY OVERNIGHT...AND THE
WINDWARD BIG ISLAND SATURDAY AND SATURDAY NIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...FOCUSING MOST
OF ITS ASSOCIATED MOISTURE ALONG WINDWARD SLOPES AND COASTS. AFTER
THE FRONT PASSES...LIGHT TO MODERATE NORTHEAST TO NORTH WINDS WILL
PREVAIL INTO EARLY NEXT WEEK...WITH BRIEF SHOWERS FAVORING
WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND MORNINGS.
HOWEVER...A CLOUD BAND MOVING OVER THE ISLANDS ON SUNDAY MAY BRING
A FEW EXTRA WINDWARD SHOWERS.

&&

.DISCUSSION...
A BAND OF LOW CLOUDS ACCOMPANIED BY SCATTERED SHOWERS MARKS A WEAK
COLD FRONT...WHICH LIES ACROSS OAHU AND MOLOKAI AS OF MID EVENING.
SOME ISOLATED HEAVY RAINS OCCURRED LATE THIS AFTERNOON OVER PARTS
OF OAHU...AND LOCALLY HEAVIER SHOWERS HAVE FIRED UP RECENTLY
ACROSS EASTERN OAHU AND MOLOKAI...REQUIRING FLOOD ADVISORIES TO BE
ISSUED. ELSEWHERE AROUND THE STATE...NORTHERLY FLOW PREVAILS
ACROSS KAUAI BEHIND THE FRONT...WITH LIGHT WINDS AND WIDELY
SCATTERED SHOWERS AROUND MAUI AND THE BIG ISLAND. SURFACE ANALYSIS
DEPICTS THE AFOREMENTIONED FRONT STRETCHING SW FROM A LOW CENTERED
ABOUT 900 MILES NNE OF PHNL...WITH A 1025 MB HIGH CENTERED ABOUT
1000 MILES NW OF KAUAI. AN UNSEASONABLY DEEP TROUGH ALOFT IS
LOCATED OVER THE CENTRAL PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT
OF THE SURFACE FRONT SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN
LATE MAY. MIMIC-TPW SATELLITE IMAGERY DEPICTS A NARROW BAND OF
SOMEWHAT ENHANCED MOISTURE ALONG THE FRONT...WITH ESTIMATED PWATS
UP TO 1.5 INCHES. THIS AGREES WELL WITH THE 00Z LIHUE SOUNDING...
WHICH FOUND A HIGH/WEAK INVERSION BASED NEAR 12K FEET AND PWAT OF
1.4 INCHES. THE 00Z HILO SOUNDING REFLECTED A DRIER AIRMASS AHEAD
OF THE FRONT...WITH THE INVERSION BASED NEAR 9500 FEET AND PWAT OF
1.19 INCHES.

OVERNIGHT AND SATURDAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING
SOUTHWARD THROUGH THE STATE. BUILDING N/NE FLOW FILTERING THROUGH
THE FRONT WILL FOCUS MOST OF THE SHOWER ACTIVITY ACROSS WINDWARD
AND MAUKA AREAS. LOCALIZED HEAVIER SHOWERS WILL REMAIN POSSIBLE
ALONG THE FRONT THROUGH AT LEAST THE REST OF THIS EVENING AND
POSSIBLY INTO LATE TONIGHT. WOULD EXPECT MOSTLY LIGHTER SHOWERS
ON SATURDAY AS LOW LEVEL CONVERGENCE ALONG THE FRONT WEAKENS.
HAVE UPDATED THE FORECAST TO BRING THE HIGH POPS FURTHER SOUTH AND
EAST ACROSS MOLOKAI AND WEST MAUI FOR THIS EVENING.

THE FRONT WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH DEW
POINTS DROPPING ABOUT 3-5 DEGREES F. THUS SLIGHTLY COOLER AND
DRIER WEATHER IS EXPECTED FOR THE SMALLER ISLANDS ON SATURDAY.

THE PARENT LOW OF THE FRONT WILL STALL FAR NNE OF THE STATE
OVERNIGHT...THEN MOVE S AND WEAKEN THROUGH THE WEEKEND...AS HIGH
PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL KEEP A RELATIVELY
COOL NE WIND FLOW OVER THE AREA. SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH
AND EAST FACING SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY
STABLE THROUGH THE PERIOD. GFS CONTINUES TO INDICATE THAT ONE WEAK
BAND OF ENHANCED MOISTURE WILL MOVE ACROSS THE STATE SUNDAY AND
SUNDAY NIGHT. NE FLOW WILL REMAIN LIGHT TO MODERATE THROUGH MONDAY...
BUT SHOULD THEN WEAKEN TOWARD THE MIDDLE OF NEXT WEEK AS LOW
PRESSURE LINGERS FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO
OUR NORTHWEST. THIS WILL LIKELY ALLOW LAND AND SEA BREEZES TO
DOMINATE THE ISLAND WIND/WEATHER ONCE AGAIN. THE LOW SHOULD FINALLY
EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING THE RETURN
OF LIGHT TO MODERATE TRADES.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL SHIFT SOUTHEAST THROUGH MAUI COUNTY
TONIGHT AND INTO THE BIG ISLAND ON SATURDAY. TEMPORARY MVFR
CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS AS THE FRONT PUSHES
THROUGH...WITH IMPROVING CONDITIONS EXPECTED BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS KAUAI
OAHU MOLOKAI AND MAUI. CONDITIONS SHOULD IMPROVE LATER TONIGHT
ACROSS KAUAI AND OAHU. THE AIRMET MAY NEED TO BE EXPANDED TO INCLUDE
LANAI LATER THIS EVENING...AND POSSIBLY PORTIONS OF THE BIG ISLAND
SATURDAY MORNING.

&&

.MARINE...
NORTHERLY WINDS INCREASED TO 19 KT LATE FRIDAY AFTERNOON AT PHBK...
AND A SMALL CRAFT ADVISORY /SCA/ IS IN EFFECT FOR THE ADJACENT
LEEWARD KAUAI COASTAL WATERS THROUGH SATURDAY. WILL KEEP AN EYE ON
OTHER AREAS OVERNIGHT TO SEE IF 25 KT WINDS MAY DEVELOP AS THE
FRONT MOVES THROUGH...BUT CURRENT FORECASTS SHOW WINDS AROUND 20
KT AT MOST. MODERATE N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD
ACROSS THE STATE OVERNIGHT AND SATURDAY...AND PREVAIL STATEWIDE
SATURDAY NIGHT AND SUNDAY. WINDS WILL THEN WEAKEN ONCE AGAIN
MONDAY...BECOMING LIGHT WITH POSSIBLE AFTERNOON SEABREEZES
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN
BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT OVERLAPPING
SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR ADVISORY-
LEVELS ALONG EXPOSED S FACING SHORES. A MODERATE NNE SWELL IS
EXPECTED TO ARRIVE ON SUNDAY AND LINGER THROUGH MONDAY...BUT
RELATIVELY SHORT SWELL PERIODS SHOULD RESULTING SURF WELL BELOW
ADVISORY LEVELS ON NORTH FACING SHORES. OTHERWISE...A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.
SEE THE LATEST OAHU SURF DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI LEEWARD
WATERS.

&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA










000
FXHW60 PHFO 230655
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
855 PM HST FRI MAY 22 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER MAUI COUNTY OVERNIGHT...AND THE
WINDWARD BIG ISLAND SATURDAY AND SATURDAY NIGHT...BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...FOCUSING MOST
OF ITS ASSOCIATED MOISTURE ALONG WINDWARD SLOPES AND COASTS. AFTER
THE FRONT PASSES...LIGHT TO MODERATE NORTHEAST TO NORTH WINDS WILL
PREVAIL INTO EARLY NEXT WEEK...WITH BRIEF SHOWERS FAVORING
WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND MORNINGS.
HOWEVER...A CLOUD BAND MOVING OVER THE ISLANDS ON SUNDAY MAY BRING
A FEW EXTRA WINDWARD SHOWERS.

&&

.DISCUSSION...
A BAND OF LOW CLOUDS ACCOMPANIED BY SCATTERED SHOWERS MARKS A WEAK
COLD FRONT...WHICH LIES ACROSS OAHU AND MOLOKAI AS OF MID EVENING.
SOME ISOLATED HEAVY RAINS OCCURRED LATE THIS AFTERNOON OVER PARTS
OF OAHU...AND LOCALLY HEAVIER SHOWERS HAVE FIRED UP RECENTLY
ACROSS EASTERN OAHU AND MOLOKAI...REQUIRING FLOOD ADVISORIES TO BE
ISSUED. ELSEWHERE AROUND THE STATE...NORTHERLY FLOW PREVAILS
ACROSS KAUAI BEHIND THE FRONT...WITH LIGHT WINDS AND WIDELY
SCATTERED SHOWERS AROUND MAUI AND THE BIG ISLAND. SURFACE ANALYSIS
DEPICTS THE AFOREMENTIONED FRONT STRETCHING SW FROM A LOW CENTERED
ABOUT 900 MILES NNE OF PHNL...WITH A 1025 MB HIGH CENTERED ABOUT
1000 MILES NW OF KAUAI. AN UNSEASONABLY DEEP TROUGH ALOFT IS
LOCATED OVER THE CENTRAL PACIFIC...SUPPORTING THE UNUSUAL MOVEMENT
OF THE SURFACE FRONT SOUTHWARD ACROSS THE MAIN HAWAIIAN ISLANDS IN
LATE MAY. MIMIC-TPW SATELLITE IMAGERY DEPICTS A NARROW BAND OF
SOMEWHAT ENHANCED MOISTURE ALONG THE FRONT...WITH ESTIMATED PWATS
UP TO 1.5 INCHES. THIS AGREES WELL WITH THE 00Z LIHUE SOUNDING...
WHICH FOUND A HIGH/WEAK INVERSION BASED NEAR 12K FEET AND PWAT OF
1.4 INCHES. THE 00Z HILO SOUNDING REFLECTED A DRIER AIRMASS AHEAD
OF THE FRONT...WITH THE INVERSION BASED NEAR 9500 FEET AND PWAT OF
1.19 INCHES.

OVERNIGHT AND SATURDAY...EXPECT THE WEAK FRONT TO CONTINUE MOVING
SOUTHWARD THROUGH THE STATE. BUILDING N/NE FLOW FILTERING THROUGH
THE FRONT WILL FOCUS MOST OF THE SHOWER ACTIVITY ACROSS WINDWARD
AND MAUKA AREAS. LOCALIZED HEAVIER SHOWERS WILL REMAIN POSSIBLE
ALONG THE FRONT THROUGH AT LEAST THE REST OF THIS EVENING AND
POSSIBLY INTO LATE TONIGHT. WOULD EXPECT MOSTLY LIGHTER SHOWERS
ON SATURDAY AS LOW LEVEL CONVERGENCE ALONG THE FRONT WEAKENS.
HAVE UPDATED THE FORECAST TO BRING THE HIGH POPS FURTHER SOUTH AND
EAST ACROSS MOLOKAI AND WEST MAUI FOR THIS EVENING.

THE FRONT WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH DEW
POINTS DROPPING ABOUT 3-5 DEGREES F. THUS SLIGHTLY COOLER AND
DRIER WEATHER IS EXPECTED FOR THE SMALLER ISLANDS ON SATURDAY.

THE PARENT LOW OF THE FRONT WILL STALL FAR NNE OF THE STATE
OVERNIGHT...THEN MOVE S AND WEAKEN THROUGH THE WEEKEND...AS HIGH
PRESSURE BUILDS FAR NW OF THE AREA. THIS WILL KEEP A RELATIVELY
COOL NE WIND FLOW OVER THE AREA. SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LOW WILL BRING SHOWERS MAINLY ACROSS THE NORTH
AND EAST FACING SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY
STABLE THROUGH THE PERIOD. GFS CONTINUES TO INDICATE THAT ONE WEAK
BAND OF ENHANCED MOISTURE WILL MOVE ACROSS THE STATE SUNDAY AND
SUNDAY NIGHT. NE FLOW WILL REMAIN LIGHT TO MODERATE THROUGH MONDAY...
BUT SHOULD THEN WEAKEN TOWARD THE MIDDLE OF NEXT WEEK AS LOW
PRESSURE LINGERS FAR TO OUR NORTH AND HIGH PRESSURE WEAKENS TO
OUR NORTHWEST. THIS WILL LIKELY ALLOW LAND AND SEA BREEZES TO
DOMINATE THE ISLAND WIND/WEATHER ONCE AGAIN. THE LOW SHOULD FINALLY
EXIT TO THE NE TOWARD THE END OF NEXT WEEK...ALLOWING THE RETURN
OF LIGHT TO MODERATE TRADES.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL SHIFT SOUTHEAST THROUGH MAUI COUNTY
TONIGHT AND INTO THE BIG ISLAND ON SATURDAY. TEMPORARY MVFR
CIGS/VSBYS WILL BE POSSIBLE AT THE TERMINALS AS THE FRONT PUSHES
THROUGH...WITH IMPROVING CONDITIONS EXPECTED BEHIND THE FRONT.

AIRMET SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ACROSS KAUAI
OAHU MOLOKAI AND MAUI. CONDITIONS SHOULD IMPROVE LATER TONIGHT
ACROSS KAUAI AND OAHU. THE AIRMET MAY NEED TO BE EXPANDED TO INCLUDE
LANAI LATER THIS EVENING...AND POSSIBLY PORTIONS OF THE BIG ISLAND
SATURDAY MORNING.

&&

.MARINE...
NORTHERLY WINDS INCREASED TO 19 KT LATE FRIDAY AFTERNOON AT PHBK...
AND A SMALL CRAFT ADVISORY /SCA/ IS IN EFFECT FOR THE ADJACENT
LEEWARD KAUAI COASTAL WATERS THROUGH SATURDAY. WILL KEEP AN EYE ON
OTHER AREAS OVERNIGHT TO SEE IF 25 KT WINDS MAY DEVELOP AS THE
FRONT MOVES THROUGH...BUT CURRENT FORECASTS SHOW WINDS AROUND 20
KT AT MOST. MODERATE N/NE FLOW IS EXPECTED TO SPREAD SOUTHWARD
ACROSS THE STATE OVERNIGHT AND SATURDAY...AND PREVAIL STATEWIDE
SATURDAY NIGHT AND SUNDAY. WINDS WILL THEN WEAKEN ONCE AGAIN
MONDAY...BECOMING LIGHT WITH POSSIBLE AFTERNOON SEABREEZES
DEVELOPING TUESDAY AND WEDNESDAY.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN
BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT OVERLAPPING
SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR ADVISORY-
LEVELS ALONG EXPOSED S FACING SHORES. A MODERATE NNE SWELL IS
EXPECTED TO ARRIVE ON SUNDAY AND LINGER THROUGH MONDAY...BUT
RELATIVELY SHORT SWELL PERIODS SHOULD RESULTING SURF WELL BELOW
ADVISORY LEVELS ON NORTH FACING SHORES. OTHERWISE...A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.
SEE THE LATEST OAHU SURF DISCUSSION /SRDHFO/ FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI LEEWARD
WATERS.

&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...JELSEMA









000
FXHW60 PHFO 230201
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST FRI MAY 22 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER OAHU THIS EVENING...MAUI COUNTY
OVERNIGHT...AND WINDWARD BIG ISLAND SATURDAY AND SATURDAY
NIGHT...BEFORE DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A
BRIEF PERIOD OF BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...
THEREBY FOCUSING MOST OF ITS ASSOCIATED MOISTURE ALONG WINDWARD
SLOPES AND COASTS. AFTER THE FRONT PASSES...LIGHT TO MODERATE
NORTHEAST TO NORTH WINDS WILL PREVAIL INTO NEXT WEEK...WITH BRIEF
SHOWERS FAVORING WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND
MORNINGS. HOWEVER...A CLOUD BAND MOVING OVER THE ISLANDS ON SUNDAY
MAY BRING A FEW EXTRA WINDWARD SHOWERS.

&&

.DISCUSSION...
A 100 TO 150 MILE WIDE...ENE-WSW ORIENTED....FRAGMENTED BAND OF
BROKEN TO OVERCAST SHOWERY LOW CLOUDS MARKS A SOMEWHAT UNSEASONABLE
COLD FRONT THAT IS MOVING SOUTH ACROSS THE ISLANDS THIS AFTERNOON.
RELATIVELY LIGHT WINDS AHEAD OF THE FRONT ALLOWED SEA BREEZES TO
DRIVE CLOUD AND SHOWER FORMATION OVER THE ISLANDS FROM OAHU TO
HAWAII THIS AFTERNOON...WITH NW STEERING FLOW PUSHING THE CLOUDS AND
SHOWERS TOWARD THE SE. WHILE N FACING SLOPES OF KAUAI HAVE RECEIVED
CLOSE TO AN INCH OF RAIN WITH THE FRONT SO FAR...E AND SE SIDES OF
OAHU HAVE RECEIVED BENEFICIAL RAINFALL DUE TO THE SEA BREEZE
CONVERGENCE.

THE LEADING EDGE OF THE FRAGMENTED CLOUD BAND IS APPROACHING OAHU
FROM THE N AT 3 PM...WITH THE BOUNDARY MOVING SOUTH AT SPEEDS
BETWEEN 10 AND 15 MPH. THE FRONT IS FORECAST TO MOVE OVER
OAHU AND MAUI COUNTY OVERNIGHT...AND THE BIG ISLAND ON SATURDAY
BEFORE FINALLY BREAKING APART SE OF THE BIG ISLAND ON SUNDAY. WINDS
ARE LIGHT AND VARIABLE AT THE SURFACE AHEAD OF THE FRONT...AND WILL
SWITCH TO THE NNE AFTER THE FRONT PASSES...AND THUS MOST OF THE
SHOWERS ASSOCIATED WITH THE BOUNDARY WILL FOCUS ALONG N AND E FACING
SLOPES AND COASTS. WITH MINIMAL SUPPORT FROM ALOFT...EXCESSIVE
RAINFALL IS NOT EXPECTED WITH THE FRONTAL PASSAGE.

AFTER THE FRONT PASSES...NE WINDS WILL EASE AND GENERALLY REMAIN
LIGHT TO MODERATE INTO THE MIDDLE OF NEXT WEEK. THE FRONT...AND
FOLLOWING NE WINDS...WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH
DEW POINTS DROPPING ABOUT 3-5 DEGREES F. THUS SLIGHTLY COOLER AND
CLEARER WEATHER IS EXPECTED ON SATURDAY...WITH THE POTENTIAL FOR A
FEW MORE WINDWARD SHOWERS ON SUNDAY.

THE LOW WITH WITH WHICH THE FRONT IS ASSOCIATED IS CURRENTLY ABOUT
750 MILES NNE OF THE ISLANDS...AND MOVING NE...BUT THE FORWARD
MOTION OF THE LOW IS EXPECTED TO HALT TONIGHT. THE LOW IS THEN
EXPECTED TO MOVE S AND WEAKEN THROUGH THE WEEKEND...AS HIGH PRESSURE
BUILDS FAR NW OF THE AREA. THIS WILL KEEP A RELATIVELY COOL NE WIND
FLOW OVER THE AREA. SHALLOW BANDS OF MOISTURE ROTATING AROUND THE
LOW WILL BRING SHOWERS THAT WILL FAVOR THE N AND E FACING
SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH
THE PERIOD. GFS CONTINUES TO INDICATE THAT ONE SUCH WEAK BAND WILL
MOVE OVER THE ISLANDS SUNDAY AND SUNDAY EVENING. THE FLOW WILL
BECOME QUITE LIGHT AT TIMES...ESPECIALLY AS WE APPROACH THE MIDDLE
PART OF NEXT WEEK...WHICH WILL LIKELY ALLOW LAND AND SEA BREEZES TO
DOMINATE THE ISLAND WIND/WEATHER. THE LOW WILL EXIT TO THE NE BY THE
SECOND HALF OF NEXT THE WEEK ALLOWING THE RETURN OF LIGHT TO
MODERATE TRADE WINDS BY THE END OF THE WEEK.

&&

.AVIATION...
THE WEAKENING COLD FRONT IS SLOWING MOVING OVER KAUAI AS OF 02Z.
PREVAILING MVFR WITH TEMPO IFR IS LIKELY AT PHLI UNTIL LATER THIS
EVENING WHEN THE FRONT MOVES TOWARDS OAHU. THE FRONT IS EXPECTED TO
BE NEAR OAHU AROUND 06Z. AS THE FRONT MOVES OVER OAHU...PHJR AND
PHNL ARE LIKELY TO SEE POSSIBLE PERIODS OF ISOL TO TEMPO MVFR IN
SELECT SHOWERS. A SIMILAR SCENARIO IS EXPECTED AT MAUI COUNTY
TERMINALS...ESPECIALLY THOSE IN WINDWARD AREAS...AFTER 10Z AS THE
FRONT CONTINUES TO MOVE DOWN THE ISLAND CHAIN. MODERATE NORTH TO
NORTHEAST WINDS WILL FILL IN BEHIND THE FRONT.

THE FRONT...OR WHAT IS LEFT OF IT...IS NOT FORECAST TO REACH THE
BIG ISLAND UNTIL SATURDAY AFTERNOON. WINDS ON THE BIG ISLAND WILL
REMAIN LIGHT AND VARIABLE ALLOWING FOR LAND BREEZES TO FORM TONIGHT.
THE LAND BREEZES WILL HELP CLEAR OUT THE CLOUDS THAT BUILT UP THIS
AFTERNOON OVER THE LOWER SLOPES. VFR WILL PREVAIL.

MOST SIGNIFICANT UPPER LEVEL TURB WILL REMAIN NORTH OF THE ISLANDS
NEAR THE CENTER OF THE DEEP LOW AT 32N 151W. AIRMET TANGO OVER THE
ISLANDS HAS BEEN CANCELLED...HOWEVER ISOL LIGHT TO MODERATE TURB
MAY OCCUR OVER AND NEAR THE ISLANDS AS THE UPPER LEVEL TROUGH
EXTENDING FROM THE LOW MOVES EAST.

&&

.MARINE...
HI-RES GUIDANCE INDICATES THAT A BRIEF SURGE IN NE WINDS IN THE
WAKE OF THE FRONTAL PASSAGE WILL BRING A PERIOD OF NEAR 25 KT WINDS
TO KAUAI LEEWARD WATERS TONIGHT AND SATURDAY...AND RECENT
OBSERVATIONS AT PHBK INDICATE 20 KT SUSTAINED WINDS...WHICH IS A
LITTLE HIGHER THAN THE GUIDANCE. THUS...A SHORT-LIVED SCA HAS BEEN
POSTED FOR THAT ZONE THROUGH SATURDAY. OTHERWISE AND ELSEWHERE...
WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA INTO THE
MIDDLE OF NEXT WEEK.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN
BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT OVERLAPPING
SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR
ADVISORY-LEVELS ALONG EXPOSED S FACING SHORES. A COUPLE OF SMALL
SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY
NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS. THE OAHU
SURF DISCUSSION /SRDHFO/ HAS BEEN UPDATED AND CONTAINS DETAILS ON
THE SOURCES OF THE SWELLS...AND

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI LEEWARD
WATERS.

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 230201
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST FRI MAY 22 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER OAHU THIS EVENING...MAUI COUNTY
OVERNIGHT...AND WINDWARD BIG ISLAND SATURDAY AND SATURDAY
NIGHT...BEFORE DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A
BRIEF PERIOD OF BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...
THEREBY FOCUSING MOST OF ITS ASSOCIATED MOISTURE ALONG WINDWARD
SLOPES AND COASTS. AFTER THE FRONT PASSES...LIGHT TO MODERATE
NORTHEAST TO NORTH WINDS WILL PREVAIL INTO NEXT WEEK...WITH BRIEF
SHOWERS FAVORING WINDWARD AREAS...ESPECIALLY DURING NIGHTS AND
MORNINGS. HOWEVER...A CLOUD BAND MOVING OVER THE ISLANDS ON SUNDAY
MAY BRING A FEW EXTRA WINDWARD SHOWERS.

&&

.DISCUSSION...
A 100 TO 150 MILE WIDE...ENE-WSW ORIENTED....FRAGMENTED BAND OF
BROKEN TO OVERCAST SHOWERY LOW CLOUDS MARKS A SOMEWHAT UNSEASONABLE
COLD FRONT THAT IS MOVING SOUTH ACROSS THE ISLANDS THIS AFTERNOON.
RELATIVELY LIGHT WINDS AHEAD OF THE FRONT ALLOWED SEA BREEZES TO
DRIVE CLOUD AND SHOWER FORMATION OVER THE ISLANDS FROM OAHU TO
HAWAII THIS AFTERNOON...WITH NW STEERING FLOW PUSHING THE CLOUDS AND
SHOWERS TOWARD THE SE. WHILE N FACING SLOPES OF KAUAI HAVE RECEIVED
CLOSE TO AN INCH OF RAIN WITH THE FRONT SO FAR...E AND SE SIDES OF
OAHU HAVE RECEIVED BENEFICIAL RAINFALL DUE TO THE SEA BREEZE
CONVERGENCE.

THE LEADING EDGE OF THE FRAGMENTED CLOUD BAND IS APPROACHING OAHU
FROM THE N AT 3 PM...WITH THE BOUNDARY MOVING SOUTH AT SPEEDS
BETWEEN 10 AND 15 MPH. THE FRONT IS FORECAST TO MOVE OVER
OAHU AND MAUI COUNTY OVERNIGHT...AND THE BIG ISLAND ON SATURDAY
BEFORE FINALLY BREAKING APART SE OF THE BIG ISLAND ON SUNDAY. WINDS
ARE LIGHT AND VARIABLE AT THE SURFACE AHEAD OF THE FRONT...AND WILL
SWITCH TO THE NNE AFTER THE FRONT PASSES...AND THUS MOST OF THE
SHOWERS ASSOCIATED WITH THE BOUNDARY WILL FOCUS ALONG N AND E FACING
SLOPES AND COASTS. WITH MINIMAL SUPPORT FROM ALOFT...EXCESSIVE
RAINFALL IS NOT EXPECTED WITH THE FRONTAL PASSAGE.

AFTER THE FRONT PASSES...NE WINDS WILL EASE AND GENERALLY REMAIN
LIGHT TO MODERATE INTO THE MIDDLE OF NEXT WEEK. THE FRONT...AND
FOLLOWING NE WINDS...WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH
DEW POINTS DROPPING ABOUT 3-5 DEGREES F. THUS SLIGHTLY COOLER AND
CLEARER WEATHER IS EXPECTED ON SATURDAY...WITH THE POTENTIAL FOR A
FEW MORE WINDWARD SHOWERS ON SUNDAY.

THE LOW WITH WITH WHICH THE FRONT IS ASSOCIATED IS CURRENTLY ABOUT
750 MILES NNE OF THE ISLANDS...AND MOVING NE...BUT THE FORWARD
MOTION OF THE LOW IS EXPECTED TO HALT TONIGHT. THE LOW IS THEN
EXPECTED TO MOVE S AND WEAKEN THROUGH THE WEEKEND...AS HIGH PRESSURE
BUILDS FAR NW OF THE AREA. THIS WILL KEEP A RELATIVELY COOL NE WIND
FLOW OVER THE AREA. SHALLOW BANDS OF MOISTURE ROTATING AROUND THE
LOW WILL BRING SHOWERS THAT WILL FAVOR THE N AND E FACING
SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH
THE PERIOD. GFS CONTINUES TO INDICATE THAT ONE SUCH WEAK BAND WILL
MOVE OVER THE ISLANDS SUNDAY AND SUNDAY EVENING. THE FLOW WILL
BECOME QUITE LIGHT AT TIMES...ESPECIALLY AS WE APPROACH THE MIDDLE
PART OF NEXT WEEK...WHICH WILL LIKELY ALLOW LAND AND SEA BREEZES TO
DOMINATE THE ISLAND WIND/WEATHER. THE LOW WILL EXIT TO THE NE BY THE
SECOND HALF OF NEXT THE WEEK ALLOWING THE RETURN OF LIGHT TO
MODERATE TRADE WINDS BY THE END OF THE WEEK.

&&

.AVIATION...
THE WEAKENING COLD FRONT IS SLOWING MOVING OVER KAUAI AS OF 02Z.
PREVAILING MVFR WITH TEMPO IFR IS LIKELY AT PHLI UNTIL LATER THIS
EVENING WHEN THE FRONT MOVES TOWARDS OAHU. THE FRONT IS EXPECTED TO
BE NEAR OAHU AROUND 06Z. AS THE FRONT MOVES OVER OAHU...PHJR AND
PHNL ARE LIKELY TO SEE POSSIBLE PERIODS OF ISOL TO TEMPO MVFR IN
SELECT SHOWERS. A SIMILAR SCENARIO IS EXPECTED AT MAUI COUNTY
TERMINALS...ESPECIALLY THOSE IN WINDWARD AREAS...AFTER 10Z AS THE
FRONT CONTINUES TO MOVE DOWN THE ISLAND CHAIN. MODERATE NORTH TO
NORTHEAST WINDS WILL FILL IN BEHIND THE FRONT.

THE FRONT...OR WHAT IS LEFT OF IT...IS NOT FORECAST TO REACH THE
BIG ISLAND UNTIL SATURDAY AFTERNOON. WINDS ON THE BIG ISLAND WILL
REMAIN LIGHT AND VARIABLE ALLOWING FOR LAND BREEZES TO FORM TONIGHT.
THE LAND BREEZES WILL HELP CLEAR OUT THE CLOUDS THAT BUILT UP THIS
AFTERNOON OVER THE LOWER SLOPES. VFR WILL PREVAIL.

MOST SIGNIFICANT UPPER LEVEL TURB WILL REMAIN NORTH OF THE ISLANDS
NEAR THE CENTER OF THE DEEP LOW AT 32N 151W. AIRMET TANGO OVER THE
ISLANDS HAS BEEN CANCELLED...HOWEVER ISOL LIGHT TO MODERATE TURB
MAY OCCUR OVER AND NEAR THE ISLANDS AS THE UPPER LEVEL TROUGH
EXTENDING FROM THE LOW MOVES EAST.

&&

.MARINE...
HI-RES GUIDANCE INDICATES THAT A BRIEF SURGE IN NE WINDS IN THE
WAKE OF THE FRONTAL PASSAGE WILL BRING A PERIOD OF NEAR 25 KT WINDS
TO KAUAI LEEWARD WATERS TONIGHT AND SATURDAY...AND RECENT
OBSERVATIONS AT PHBK INDICATE 20 KT SUSTAINED WINDS...WHICH IS A
LITTLE HIGHER THAN THE GUIDANCE. THUS...A SHORT-LIVED SCA HAS BEEN
POSTED FOR THAT ZONE THROUGH SATURDAY. OTHERWISE AND ELSEWHERE...
WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA INTO THE
MIDDLE OF NEXT WEEK.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES FOR THE NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN
BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT OVERLAPPING
SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR
ADVISORY-LEVELS ALONG EXPOSED S FACING SHORES. A COUPLE OF SMALL
SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY
NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS. THE OAHU
SURF DISCUSSION /SRDHFO/ HAS BEEN UPDATED AND CONTAINS DETAILS ON
THE SOURCES OF THE SWELLS...AND

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI LEEWARD
WATERS.

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 222016
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1015 AM HST FRI MAY 22 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER KAUAI THIS AFTERNOON...OAHU THIS
EVENING...AND MAUI COUNTY OVERNIGHT AND SATURDAY. THE FRONT WILL
REACH WINDWARD BIG ISLAND SATURDAY AND SATURDAY NIGHT BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...THEREBY FOCUSING
MOST OF ITS ASSOCIATED MOISTURE ALONG WINDWARD SLOPES AND COASTS.
AFTER THE FRONT PASSES...LIGHT TO MODERATE NORTHEAST TO NORTH WINDS
WILL PREVAIL INTO NEXT WEEK...DELIVERING BRIEF WINDWARD SHOWERS...
MAINLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
A 100 TO 150 MILE WIDE ENE-WSW ORIENTED BAND OF BROKEN TO OVERCAST
SHOWERY LOW CLOUDS MARKS A COLD FRONT THAT IS EASING SOUTHWARD
TOWARD THE ISLANDS THIS MORNING. THE LEADING EDGE OF THE FRAGMENTED
CLOUD BAND IS NEAR KAUAI AT 10 AM...WITH THE BOUNDARY MOVING SOUTH
AT SPEEDS BETWEEN 10 AND 15 MPH. THE FRONT IS FORECAST TO MOVE OVER
KAUAI TODAY...OAHU/MAUI COUNTY TONIGHT...AND THE BIG ISLAND ON
SATURDAY BEFORE FINALLY BREAKING APART SE OF THE BIG ISLAND ON
SUNDAY. WINDS ARE LIGHT AND VARIABLE AT THE SURFACE AHEAD OF THE
FRONT...AND WILL SWITCH TO THE NNE AFTER THE FRONT PASSES...AND THUS
MOST OF THE SHOWERS ASSOCIATED WITH THE BOUNDARY WILL FOCUS ALONG N
AND E FACING SLOPES AND COASTS. WITH MINIMAL SUPPORT FROM ALOFT...
EXCESSIVE RAINFALL IS NOT EXPECTED WITH THE FRONTAL PASSAGE.

AFTER THE FRONT PASSES...NE WINDS WILL EASE AND GENERALLY REMAIN
LIGHT TO MODERATE INTO THE MIDDLE OF NEXT WEEK. THE FRONT...AND
FOLLOWING NE WINDS...WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH
DEW POINTS DROPPING ABOUT 5 DEGREES F.

THE LOW WITH WITH WHICH THE FRONT IS ASSOCIATED IS CURRENTLY ABOUT
700 MILES NNE OF THE ISLANDS...AND MOVING NE...BUT THIS MOTION IS
EXPECTED TO HALT LATER TODAY. THE LOW IS THEN EXPECTED TO MOVE S AND
WEAKEN THROUGH THE WEEKEND...AS HIGH PRESSURE BUILDS FAR NW OF THE
AREA. THIS WILL KEEP A RELATIVELY COOL NE WIND FLOW OVER THE AREA...
BUT THE FLOW WILL BECOME QUITE LIGHT AT TIMES...ESPECIALLY AS WE
APPROACH THE MIDDLE PART OF NEXT WEEK. SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LOW WILL FAVOR THE N AND E FACING SLOPES...BUT
THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH THE PERIOD. GFS
CONTINUES TO INDICATE THAT ONE SUCH WEAK BAND WILL MOVE OVER THE
ISLANDS SUNDAY AND SUNDAY EVENING. OTHERWISE...LAND AND SEA BREEZES
MAY DOMINATE THE ISLAND WIND/WEATHER PATTERN EARLY NEXT WEEK WHEN
THE SYNOPTIC SCALE FLOW BECOMES QUITE WEAK. THE LOW WILL EXIT TO THE
NE BY THE SECOND HALF OF NEXT THE WEEK ALLOWING THE RETURN OF LIGHT
TO MODERATE TRADE WINDS BY THE END OF THE WEEK.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL MOVE THROUGH KAUAI THIS AFTERNOON AND
MAUI COUNTY TONIGHT. WINDS AHEAD OF THE FRONT REMAIN LIGHT AND SEA
BREEZES WILL TAKE HOLD BY THIS AFTERNOON. MODERATE NORTH TO
NORTHEAST WINDS WILL FILL IN BEHIND THE FRONT.

SEA BREEZES WILL INTRODUCE THE CHANCE FOR INTERIOR CLOUDS AND
SHOWERS THIS AFTERNOON...ESPECIALLY OVER LEEWARD BIG ISLAND.
TOWERING CUMULUS WITH TOPS REACHING 20 KFT CAN NOT BE RULED OUT. AS
THE FRONT PASSES INDIVIDUAL ISLANDS...CLOUDS AND SHOWERS WILL BEGIN
TO FOCUS ALONG WINDWARD AND MOUNTAIN AREAS. MOUNTAIN OBSCURATION
COULD BECOME A PROBLEM THIS AFTERNOON AS THE FRONT MOVES DOWN THE
ISLAND CHAIN.

GUIDANCE IS SUGGESTING UPPER LEVEL LIGHT TO MODERATE TURBULENCE
PASSING WEST TO EAST OVER THE ISLANDS AS THE FRONT MOVED DOWN THE
ISLAND CHAIN. A FEW PILOT REPORTS FROM THIS MORNING PLACE THE
TURBULENCE BETWEEN FL300 AND FL390. AIRMET TANGO FOR UPPER LEVEL
TURB IS POSTED.

&&

.MARINE...
THE EXPECTATION HAS BEEN THAT WINDS AND SEAS WILL REMAIN BELOW SMALL
CRAFT ADVISORY /SCA/ CRITERIA FOR ALL WATERS INTO NEXT WEEK...BUT
NOW THERE IS A SLIGHT CAVEAT. LATEST HI-RES GUIDANCE HOWEVER
INDICATES THAT A BRIEF SURGE IN NE WINDS IN THE WAKE OF THE FRONTAL
PASSAGE COULD BRING A PERIOD OF NEAR 25 KT WINDS TO KAUAI LEEWARD
WATERS TONIGHT AND SATURDAY...AND A SHORT-LIVED SCA MAY BE POSTED
LATER TODAY FOR THAT AREA.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES INTO THE END OF NEXT WEEK. SURF HEIGHTS ARE EXPECTED
TO REMAIN BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT
OVERLAPPING SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR
ADVISORY-LEVELS ALONG EXPOSED S FACING SHORES. A COUPLE OF SMALL
SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY
NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 222016
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1015 AM HST FRI MAY 22 2015

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE OVER KAUAI THIS AFTERNOON...OAHU THIS
EVENING...AND MAUI COUNTY OVERNIGHT AND SATURDAY. THE FRONT WILL
REACH WINDWARD BIG ISLAND SATURDAY AND SATURDAY NIGHT BEFORE
DISSIPATING SOUTH OF THE BIG ISLAND ON SUNDAY. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...THEREBY FOCUSING
MOST OF ITS ASSOCIATED MOISTURE ALONG WINDWARD SLOPES AND COASTS.
AFTER THE FRONT PASSES...LIGHT TO MODERATE NORTHEAST TO NORTH WINDS
WILL PREVAIL INTO NEXT WEEK...DELIVERING BRIEF WINDWARD SHOWERS...
MAINLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
A 100 TO 150 MILE WIDE ENE-WSW ORIENTED BAND OF BROKEN TO OVERCAST
SHOWERY LOW CLOUDS MARKS A COLD FRONT THAT IS EASING SOUTHWARD
TOWARD THE ISLANDS THIS MORNING. THE LEADING EDGE OF THE FRAGMENTED
CLOUD BAND IS NEAR KAUAI AT 10 AM...WITH THE BOUNDARY MOVING SOUTH
AT SPEEDS BETWEEN 10 AND 15 MPH. THE FRONT IS FORECAST TO MOVE OVER
KAUAI TODAY...OAHU/MAUI COUNTY TONIGHT...AND THE BIG ISLAND ON
SATURDAY BEFORE FINALLY BREAKING APART SE OF THE BIG ISLAND ON
SUNDAY. WINDS ARE LIGHT AND VARIABLE AT THE SURFACE AHEAD OF THE
FRONT...AND WILL SWITCH TO THE NNE AFTER THE FRONT PASSES...AND THUS
MOST OF THE SHOWERS ASSOCIATED WITH THE BOUNDARY WILL FOCUS ALONG N
AND E FACING SLOPES AND COASTS. WITH MINIMAL SUPPORT FROM ALOFT...
EXCESSIVE RAINFALL IS NOT EXPECTED WITH THE FRONTAL PASSAGE.

AFTER THE FRONT PASSES...NE WINDS WILL EASE AND GENERALLY REMAIN
LIGHT TO MODERATE INTO THE MIDDLE OF NEXT WEEK. THE FRONT...AND
FOLLOWING NE WINDS...WILL USHER IN A SLIGHTLY DRIER AIR MASS...WITH
DEW POINTS DROPPING ABOUT 5 DEGREES F.

THE LOW WITH WITH WHICH THE FRONT IS ASSOCIATED IS CURRENTLY ABOUT
700 MILES NNE OF THE ISLANDS...AND MOVING NE...BUT THIS MOTION IS
EXPECTED TO HALT LATER TODAY. THE LOW IS THEN EXPECTED TO MOVE S AND
WEAKEN THROUGH THE WEEKEND...AS HIGH PRESSURE BUILDS FAR NW OF THE
AREA. THIS WILL KEEP A RELATIVELY COOL NE WIND FLOW OVER THE AREA...
BUT THE FLOW WILL BECOME QUITE LIGHT AT TIMES...ESPECIALLY AS WE
APPROACH THE MIDDLE PART OF NEXT WEEK. SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LOW WILL FAVOR THE N AND E FACING SLOPES...BUT
THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH THE PERIOD. GFS
CONTINUES TO INDICATE THAT ONE SUCH WEAK BAND WILL MOVE OVER THE
ISLANDS SUNDAY AND SUNDAY EVENING. OTHERWISE...LAND AND SEA BREEZES
MAY DOMINATE THE ISLAND WIND/WEATHER PATTERN EARLY NEXT WEEK WHEN
THE SYNOPTIC SCALE FLOW BECOMES QUITE WEAK. THE LOW WILL EXIT TO THE
NE BY THE SECOND HALF OF NEXT THE WEEK ALLOWING THE RETURN OF LIGHT
TO MODERATE TRADE WINDS BY THE END OF THE WEEK.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL MOVE THROUGH KAUAI THIS AFTERNOON AND
MAUI COUNTY TONIGHT. WINDS AHEAD OF THE FRONT REMAIN LIGHT AND SEA
BREEZES WILL TAKE HOLD BY THIS AFTERNOON. MODERATE NORTH TO
NORTHEAST WINDS WILL FILL IN BEHIND THE FRONT.

SEA BREEZES WILL INTRODUCE THE CHANCE FOR INTERIOR CLOUDS AND
SHOWERS THIS AFTERNOON...ESPECIALLY OVER LEEWARD BIG ISLAND.
TOWERING CUMULUS WITH TOPS REACHING 20 KFT CAN NOT BE RULED OUT. AS
THE FRONT PASSES INDIVIDUAL ISLANDS...CLOUDS AND SHOWERS WILL BEGIN
TO FOCUS ALONG WINDWARD AND MOUNTAIN AREAS. MOUNTAIN OBSCURATION
COULD BECOME A PROBLEM THIS AFTERNOON AS THE FRONT MOVES DOWN THE
ISLAND CHAIN.

GUIDANCE IS SUGGESTING UPPER LEVEL LIGHT TO MODERATE TURBULENCE
PASSING WEST TO EAST OVER THE ISLANDS AS THE FRONT MOVED DOWN THE
ISLAND CHAIN. A FEW PILOT REPORTS FROM THIS MORNING PLACE THE
TURBULENCE BETWEEN FL300 AND FL390. AIRMET TANGO FOR UPPER LEVEL
TURB IS POSTED.

&&

.MARINE...
THE EXPECTATION HAS BEEN THAT WINDS AND SEAS WILL REMAIN BELOW SMALL
CRAFT ADVISORY /SCA/ CRITERIA FOR ALL WATERS INTO NEXT WEEK...BUT
NOW THERE IS A SLIGHT CAVEAT. LATEST HI-RES GUIDANCE HOWEVER
INDICATES THAT A BRIEF SURGE IN NE WINDS IN THE WAKE OF THE FRONTAL
PASSAGE COULD BRING A PERIOD OF NEAR 25 KT WINDS TO KAUAI LEEWARD
WATERS TONIGHT AND SATURDAY...AND A SHORT-LIVED SCA MAY BE POSTED
LATER TODAY FOR THAT AREA.

AN EXTENDED RUN OF S SWELL...GENERATED BY SEVERAL LOWS IN THE DEEP S
PACIFIC OVER THE LAST WEEK...WILL BRING SOMEWHAT ELEVATED SURF TO S
FACING SHORES INTO THE END OF NEXT WEEK. SURF HEIGHTS ARE EXPECTED
TO REMAIN BELOW ADVISORY LEVELS FOR THE BULK OF THE TIME...BUT
OVERLAPPING SWELLS FROM SUNDAY INTO TUESDAY COULD BRING SURF TO NEAR
ADVISORY-LEVELS ALONG EXPOSED S FACING SHORES. A COUPLE OF SMALL
SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY
NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 221415
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST FRI MAY 22 2015

.SYNOPSIS...
A DISSIPATING FRONT WILL BE MOVING DOWN THE ISLAND CHAIN BETWEEN
TODAY AND SATURDAY...BRINGING WITH IT SOME SCATTERED SHOWERS. IN THE
WAKE OF THE FRONT...LIGHT TO MODERATE NORTHEAST WINDS WILL SETTLE
IN...LINGERING INTO NEXT WEEK.

&&

.DISCUSSION...
A LIGHT BUT CONVERGENT CYCLONIC WESTERLY WIND FLOW JUST ABOVE THE
SURFACE HAS TAKEN OVER THE MAIN HAWAIIAN ISLANDS WITH NW WINDS OVER
KAUAI...WESTERLY OVER THE CENTRAL ISLANDS AND S TO SW OVER THE BIG
ISLAND. RADAR IS PAINTING ISOLATED SHOWERS AHEAD OF THE FRONT
COVERING A WIDE AREA OF OUR SURROUNDING WATERS. BUT THE MOST
THREATENING OF THESE SHOWERS ARE CLOSE TO REACHING THE NORTH SHORE
OF OAHU AND THE LEEWARD KOHALA COAST OF THE BIG ISLAND. TO SOME
DEGREE AN OFFSHORE FLOW FROM THESE TWO PLACES IS SLOWING DOWN THESE
SHOWERS FROM COMING ASHORE BUT EVENTUALLY THEY WILL MAKE IT.
THUS...THIS HAS TROMPED ME TO INCLUDE ISOLATED TO SCATTERED SHOWERS
FOR THE SURROUNDING WATER WITH EMPHASIS TO THESE TWO AREAS FOR
THE NEXT COUPLE OF HOURS.

A WEAKENING/DISSIPATING FRONT IS LOCATED 90 MILES NW OF KAUAI THIS
EARLY FRIDAY MORNING...MOVING SE AT 15 MPH WITH A POSSIBLE SLOWING
DOWN AFTER REACHING KAUAI. THE VERY LATEST ECMWF AND GFS HAVE
SLOWED DOWN THE FRONT UP TO 6 HOURS. SO...FOR KAUAI...INSTEAD OF 11
AM OR NOON...IT WILL BE MID AFTERNOON. FOR OAHU...IT IS EARLY THIS
EVENING. THE NAM SOLUTION ON THE OTHER HAND...IS TAD FASTER WITH THE
ORIGINAL TIME LINE OF ABOUT NOON FOR KAUAI. THE NAM HAS THE FRONT
SLOWING DOWN SLIGHTLY UPON REACHING OAHU LATE THIS AFTERNOON...MAUI
COUNTY OVERNIGHT...AND THE BIG ISLAND EARLY SATURDAY MORNING. NAM IS
THE ACCEPTED SOLUTION.

REMNANTS OF THE FRONT ARE EXPECTED TO REACH THE BIG ISLAND SATURDAY
WHERE IT WILL LINGER THROUGH SUNDAY MORNING. THE FRONT WILL USHER IN
NOT ONLY A MODERATE NORTHEASTERLY WIND FLOW BUT A SLIGHTLY DRIER AIR
MASS AS WELL.

NO UPPER LEVEL SUPPORT FOR THE FRONT AS THE UPPER TROUGH WILL BE
RUNNING OUT AHEAD OF IT. SO NO EXCESSIVE RAINFALL EXPECTED. THE
DEPTH OF THE MOISTURE ASSOCIATED WITH THE FRONT WILL BE CONFINED TO
WITHIN 12K FEET OF THE SURFACE.

THE LOW THAT HELPED TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER 900 MILES NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK WHILE HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS
JUXTAPOSITION OF FEATURES WILL LEAD TO UNSEASONABLE N/NE WINDS FOR
THE MOST OF THE FORECAST PERIOD WITH LIGHT TO MODERATE SPEEDS.
AS THE LOW TAKES A DIP TO THE S EARLY NEXT WEEK...WINDS MAY BECOME
LIGHT ENOUGH TO ALLOW LOCAL LAND/SEA BREEZES TO DOMINATE THE ISLAND
WEATHER PATTERN. OTHERWISE...SHALLOW BANDS OF MOISTURE ROTATING
AROUND THE LOW MAY FAVOR THE N AND E FACING SLOPES...BUT THE
ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH THE PERIOD. THE LOW
WILL EXIT TO THE NE BY THE SECOND HALF OF NEXT THE WEEK ALLOWING THE
RETURN OF LIGHT TO MODERATE TRADE WINDS.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL MOVE THROUGH KAUAI AROUND
22/2200Z...THROUGH OAHU BY 23/0400Z AND INTO MAUI COUNTY TONIGHT.
EXPECT SCATTERED SHOWERS TO DEVELOP ALONG AND IN ADVANCE OF THE COLD
FRONT AS IT SHIFTS SOUTHEASTWARD...BUT PREDOMINANTLY VFR CONDITIONS
ARE EXPECTED AT ALL TAF SITES THROUGH 23/12Z.

NO AIRMETS ARE IN EFFECT AND NONE ARE ANTICIPATED THROUGH THE
MORNING HOURS. MOUNTAIN OBSCURATION COULD BECOME A PROBLEM THIS
AFTERNOON ACROSS KAUAI BEHIND THE COLD FRONT.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
A SLIGHT RISE IN THE SURF FOR THE S FACING SHORES INTO THE MIDDLE OF
NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS
FOR THE BULK OF THE TIME...BUT OVERLAPPING SWELLS SUNDAY/MONDAY
COULD BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE
OF SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...LAU
AVIATION...JELSEMA









000
FXHW60 PHFO 221415
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST FRI MAY 22 2015

.SYNOPSIS...
A DISSIPATING FRONT WILL BE MOVING DOWN THE ISLAND CHAIN BETWEEN
TODAY AND SATURDAY...BRINGING WITH IT SOME SCATTERED SHOWERS. IN THE
WAKE OF THE FRONT...LIGHT TO MODERATE NORTHEAST WINDS WILL SETTLE
IN...LINGERING INTO NEXT WEEK.

&&

.DISCUSSION...
A LIGHT BUT CONVERGENT CYCLONIC WESTERLY WIND FLOW JUST ABOVE THE
SURFACE HAS TAKEN OVER THE MAIN HAWAIIAN ISLANDS WITH NW WINDS OVER
KAUAI...WESTERLY OVER THE CENTRAL ISLANDS AND S TO SW OVER THE BIG
ISLAND. RADAR IS PAINTING ISOLATED SHOWERS AHEAD OF THE FRONT
COVERING A WIDE AREA OF OUR SURROUNDING WATERS. BUT THE MOST
THREATENING OF THESE SHOWERS ARE CLOSE TO REACHING THE NORTH SHORE
OF OAHU AND THE LEEWARD KOHALA COAST OF THE BIG ISLAND. TO SOME
DEGREE AN OFFSHORE FLOW FROM THESE TWO PLACES IS SLOWING DOWN THESE
SHOWERS FROM COMING ASHORE BUT EVENTUALLY THEY WILL MAKE IT.
THUS...THIS HAS TROMPED ME TO INCLUDE ISOLATED TO SCATTERED SHOWERS
FOR THE SURROUNDING WATER WITH EMPHASIS TO THESE TWO AREAS FOR
THE NEXT COUPLE OF HOURS.

A WEAKENING/DISSIPATING FRONT IS LOCATED 90 MILES NW OF KAUAI THIS
EARLY FRIDAY MORNING...MOVING SE AT 15 MPH WITH A POSSIBLE SLOWING
DOWN AFTER REACHING KAUAI. THE VERY LATEST ECMWF AND GFS HAVE
SLOWED DOWN THE FRONT UP TO 6 HOURS. SO...FOR KAUAI...INSTEAD OF 11
AM OR NOON...IT WILL BE MID AFTERNOON. FOR OAHU...IT IS EARLY THIS
EVENING. THE NAM SOLUTION ON THE OTHER HAND...IS TAD FASTER WITH THE
ORIGINAL TIME LINE OF ABOUT NOON FOR KAUAI. THE NAM HAS THE FRONT
SLOWING DOWN SLIGHTLY UPON REACHING OAHU LATE THIS AFTERNOON...MAUI
COUNTY OVERNIGHT...AND THE BIG ISLAND EARLY SATURDAY MORNING. NAM IS
THE ACCEPTED SOLUTION.

REMNANTS OF THE FRONT ARE EXPECTED TO REACH THE BIG ISLAND SATURDAY
WHERE IT WILL LINGER THROUGH SUNDAY MORNING. THE FRONT WILL USHER IN
NOT ONLY A MODERATE NORTHEASTERLY WIND FLOW BUT A SLIGHTLY DRIER AIR
MASS AS WELL.

NO UPPER LEVEL SUPPORT FOR THE FRONT AS THE UPPER TROUGH WILL BE
RUNNING OUT AHEAD OF IT. SO NO EXCESSIVE RAINFALL EXPECTED. THE
DEPTH OF THE MOISTURE ASSOCIATED WITH THE FRONT WILL BE CONFINED TO
WITHIN 12K FEET OF THE SURFACE.

THE LOW THAT HELPED TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER 900 MILES NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK WHILE HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS
JUXTAPOSITION OF FEATURES WILL LEAD TO UNSEASONABLE N/NE WINDS FOR
THE MOST OF THE FORECAST PERIOD WITH LIGHT TO MODERATE SPEEDS.
AS THE LOW TAKES A DIP TO THE S EARLY NEXT WEEK...WINDS MAY BECOME
LIGHT ENOUGH TO ALLOW LOCAL LAND/SEA BREEZES TO DOMINATE THE ISLAND
WEATHER PATTERN. OTHERWISE...SHALLOW BANDS OF MOISTURE ROTATING
AROUND THE LOW MAY FAVOR THE N AND E FACING SLOPES...BUT THE
ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH THE PERIOD. THE LOW
WILL EXIT TO THE NE BY THE SECOND HALF OF NEXT THE WEEK ALLOWING THE
RETURN OF LIGHT TO MODERATE TRADE WINDS.

&&

.AVIATION...
A WEAKENING COLD FRONT WILL MOVE THROUGH KAUAI AROUND
22/2200Z...THROUGH OAHU BY 23/0400Z AND INTO MAUI COUNTY TONIGHT.
EXPECT SCATTERED SHOWERS TO DEVELOP ALONG AND IN ADVANCE OF THE COLD
FRONT AS IT SHIFTS SOUTHEASTWARD...BUT PREDOMINANTLY VFR CONDITIONS
ARE EXPECTED AT ALL TAF SITES THROUGH 23/12Z.

NO AIRMETS ARE IN EFFECT AND NONE ARE ANTICIPATED THROUGH THE
MORNING HOURS. MOUNTAIN OBSCURATION COULD BECOME A PROBLEM THIS
AFTERNOON ACROSS KAUAI BEHIND THE COLD FRONT.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
A SLIGHT RISE IN THE SURF FOR THE S FACING SHORES INTO THE MIDDLE OF
NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS
FOR THE BULK OF THE TIME...BUT OVERLAPPING SWELLS SUNDAY/MONDAY
COULD BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE
OF SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...LAU
AVIATION...JELSEMA








000
FXHW60 PHFO 220631
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
820 PM HST THU MAY 21 2015

.SYNOPSIS...
THE AFTERNOON CLOUDS WILL GIVE WAY TO FAIR SKIES OVERNIGHT.
THEN A DISSIPATING FRONT WILL MOVE DOWN THE ISLAND CHAIN BETWEEN
FRIDAY THROUGH SATURDAY...BRINGING WITH IT SOME SCATTERED SHOWERS.
IN THE WAKE OF THE FRONT...LIGHT TO MODERATE NORTHEAST WINDS WILL
SETTLE IN LINGERING INTO NEXT WEEK...AND RESUME A TRADE WIND REGIME
WITH SHOWERS FAVORING THE WINDWARD AND MOUNTAIN AREAS.



&&

.DISCUSSION...
A LIGHT NW WIND FLOW HAS SPREAD DOWN TO MOLOKAI FROM THE W THIS
EVENING AHEAD OF A DISSIPATING FRONT. THIS FLOW HAS EITHER THINNED
OR CHASED AWAY ANY AFTERNOON CLOUDS AND SHOWERS THAT FORMED ON KAUAI
OAHU AND MOLOKAI. THE FLOW PATTERN HAS ALSO PREVENTED ANY VOG FROM
REACHING ANY OF THE SMALLER ISLANDS. THIS NW FLOW WILL BECOME MORE
NORTHERLY AS THE NIGHT PROGRESSES WHERE IT MAY CARRY IN A STRAY
LIGHT SHOWER OR TWO ONTO THE WINDWARD AND MAUKA AREAS OF THESE
ISLANDS. LIGHT AND VARIABLE WINDS WILL CONTINUE OVERNIGHT OVER MAUI
AND LANAI AS THEY ARE NEAR A LOW LEVEL TROUGH. LIGHT WEST TO
NORTHWEST WINDS WILL EASE IN AHEAD OF THE FRONT FRIDAY. AS FOR THE
BIG ISLAND...LIGHT SOUTHERLY WINDS WILL PERSIST INTO FRIDAY.

AT 7 PM HST...THE FRONT IS 100 MILES NORTH NORTHWEST OF KAUAI. IT IS
FORECAST TO REACH KAUAI BY NOON FRIDAY FOLLOWED BY OAHU AT MID
AFTERNOON...THEN DRAG ACROSS MAUI COUNTY FRIDAY NIGHT...DISSIPATING
ALONG THE WAY. THE REMNANTS OF THE FRONT ARE EXPECTED TO REACH THE
BIG ISLAND SATURDAY WHERE IT WILL LINGER THROUGH THE WEEKEND WITH
THE WINDWARD SIDE GETTING THE BRUNT OF IT. THE FRONT WILL USHER IN
NOT ONLY A MODERATE NORTHEASTERLY WIND FLOW BUT A SLIGHTLY DRIER AIR
MASS MOSTLY FELT ON KAUAI AND OAHU.

NO UPPER LEVEL SUPPORT FOR THE FRONT AS THE UPPER TROUGH WILL BE
RUNNING OUT AHEAD OF IT. SO NO EXCESSIVE RAINFALL EXPECTED. THE
DEPTH OF THE MOISTURE ASSOCIATED WITH THE FRONT WILL BE CONFINED TO
NO HIGHER THAN 12K FEET.

THE LOW THAT HELPED TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER 900 MILES NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK WHILE HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS
JUXTAPOSITION OF FEATURES WILL LEAD TO UNSEASONABLE N/NE WINDS FOR
THE BULK OF THE FORECAST PERIOD...ALTHOUGH SPEEDS WILL BE LIGHT TO
LOCALLY MODERATE.  AS THE LOW MAKES A JOG TO THE S EARLY NEXT
WEEK...WINDS MAY BECOME LIGHT ENOUGH TO ALLOW LOCAL LAND/SEA BREEZES
TO DOMINATE THE ISLAND WEATHER PATTERN. OTHERWISE...SHALLOW BANDS OF
MOISTURE ROTATING AROUND THE LOW MAY FAVOR THE N AND E FACING
SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH
THE PERIOD. THE LOW WILL EXIT TO THE NE BY THE SECOND HALF OF NEXT
THE WEEK ALLOWING THE RETURN OF LIGHT TO MODERATE TRADE WINDS.

&&

.AVIATION...
A WEAKENING COLD FRONT NW OF KAUAI WILL MOVE THROUGH KAUAI LATE
FRIDAY MORNING AND PUSH SOUTHWARD THROUGH OAHU FRIDAY AFTERNOON AND
INTO MAUI COUNTY FRIDAY NIGHT. CAN/T RULE OUT A FEW ISOLATED SHOWERS
ALONG AND IN ADVANCE OF THE COLD FRONT...BUT PREDOMINANTLY VFR
CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH 23/06Z.

NO AIRMETS ARE IN EFFECT AND NONE ARE ANTICIPATED THROUGH THE NIGHT.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
A SLIGHT RISE IN THE SURF FOR THE S FACING SHORES INTO THE MIDDLE OF
NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS
FOR THE BULK OF THE TIME...BUT OVERLAPPING SWELLS SUNDAY/MONDAY
COULD BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE
OF SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...LAU
AVIATION...JELSEMA







000
FXHW60 PHFO 220631
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
820 PM HST THU MAY 21 2015

.SYNOPSIS...
THE AFTERNOON CLOUDS WILL GIVE WAY TO FAIR SKIES OVERNIGHT.
THEN A DISSIPATING FRONT WILL MOVE DOWN THE ISLAND CHAIN BETWEEN
FRIDAY THROUGH SATURDAY...BRINGING WITH IT SOME SCATTERED SHOWERS.
IN THE WAKE OF THE FRONT...LIGHT TO MODERATE NORTHEAST WINDS WILL
SETTLE IN LINGERING INTO NEXT WEEK...AND RESUME A TRADE WIND REGIME
WITH SHOWERS FAVORING THE WINDWARD AND MOUNTAIN AREAS.



&&

.DISCUSSION...
A LIGHT NW WIND FLOW HAS SPREAD DOWN TO MOLOKAI FROM THE W THIS
EVENING AHEAD OF A DISSIPATING FRONT. THIS FLOW HAS EITHER THINNED
OR CHASED AWAY ANY AFTERNOON CLOUDS AND SHOWERS THAT FORMED ON KAUAI
OAHU AND MOLOKAI. THE FLOW PATTERN HAS ALSO PREVENTED ANY VOG FROM
REACHING ANY OF THE SMALLER ISLANDS. THIS NW FLOW WILL BECOME MORE
NORTHERLY AS THE NIGHT PROGRESSES WHERE IT MAY CARRY IN A STRAY
LIGHT SHOWER OR TWO ONTO THE WINDWARD AND MAUKA AREAS OF THESE
ISLANDS. LIGHT AND VARIABLE WINDS WILL CONTINUE OVERNIGHT OVER MAUI
AND LANAI AS THEY ARE NEAR A LOW LEVEL TROUGH. LIGHT WEST TO
NORTHWEST WINDS WILL EASE IN AHEAD OF THE FRONT FRIDAY. AS FOR THE
BIG ISLAND...LIGHT SOUTHERLY WINDS WILL PERSIST INTO FRIDAY.

AT 7 PM HST...THE FRONT IS 100 MILES NORTH NORTHWEST OF KAUAI. IT IS
FORECAST TO REACH KAUAI BY NOON FRIDAY FOLLOWED BY OAHU AT MID
AFTERNOON...THEN DRAG ACROSS MAUI COUNTY FRIDAY NIGHT...DISSIPATING
ALONG THE WAY. THE REMNANTS OF THE FRONT ARE EXPECTED TO REACH THE
BIG ISLAND SATURDAY WHERE IT WILL LINGER THROUGH THE WEEKEND WITH
THE WINDWARD SIDE GETTING THE BRUNT OF IT. THE FRONT WILL USHER IN
NOT ONLY A MODERATE NORTHEASTERLY WIND FLOW BUT A SLIGHTLY DRIER AIR
MASS MOSTLY FELT ON KAUAI AND OAHU.

NO UPPER LEVEL SUPPORT FOR THE FRONT AS THE UPPER TROUGH WILL BE
RUNNING OUT AHEAD OF IT. SO NO EXCESSIVE RAINFALL EXPECTED. THE
DEPTH OF THE MOISTURE ASSOCIATED WITH THE FRONT WILL BE CONFINED TO
NO HIGHER THAN 12K FEET.

THE LOW THAT HELPED TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER 900 MILES NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK WHILE HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS
JUXTAPOSITION OF FEATURES WILL LEAD TO UNSEASONABLE N/NE WINDS FOR
THE BULK OF THE FORECAST PERIOD...ALTHOUGH SPEEDS WILL BE LIGHT TO
LOCALLY MODERATE.  AS THE LOW MAKES A JOG TO THE S EARLY NEXT
WEEK...WINDS MAY BECOME LIGHT ENOUGH TO ALLOW LOCAL LAND/SEA BREEZES
TO DOMINATE THE ISLAND WEATHER PATTERN. OTHERWISE...SHALLOW BANDS OF
MOISTURE ROTATING AROUND THE LOW MAY FAVOR THE N AND E FACING
SLOPES...BUT THE ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH
THE PERIOD. THE LOW WILL EXIT TO THE NE BY THE SECOND HALF OF NEXT
THE WEEK ALLOWING THE RETURN OF LIGHT TO MODERATE TRADE WINDS.

&&

.AVIATION...
A WEAKENING COLD FRONT NW OF KAUAI WILL MOVE THROUGH KAUAI LATE
FRIDAY MORNING AND PUSH SOUTHWARD THROUGH OAHU FRIDAY AFTERNOON AND
INTO MAUI COUNTY FRIDAY NIGHT. CAN/T RULE OUT A FEW ISOLATED SHOWERS
ALONG AND IN ADVANCE OF THE COLD FRONT...BUT PREDOMINANTLY VFR
CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH 23/06Z.

NO AIRMETS ARE IN EFFECT AND NONE ARE ANTICIPATED THROUGH THE NIGHT.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
A SLIGHT RISE IN THE SURF FOR THE S FACING SHORES INTO THE MIDDLE OF
NEXT WEEK. SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS
FOR THE BULK OF THE TIME...BUT OVERLAPPING SWELLS SUNDAY/MONDAY
COULD BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE
OF SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND
AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...LAU
AVIATION...JELSEMA








000
FXHW60 PHFO 220131
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
330 PM HST THU MAY 21 2015

.SYNOPSIS...
LIGHT AND VARIABLE WINDS WILL ALLOW CLOUDS AND A FEW SHOWERS TO
LINGER INTO THIS EVENING...AND THEN GRADUALLY DISSIPATE OVERNIGHT. A
WEAK FRONT...CURRENTLY NORTH OF THE ISLANDS...WILL MOVE OVER KAUAI
FRIDAY MORNING...AND THEN MOVE DOWN THE ISLAND CHAIN TO OAHU AND
MAUI COUNTY FROM LATE FRIDAY INTO SATURDAY. THE FRONT WILL
DISSIPATE NEAR THE BIG ISLAND SATURDAY NIGHT. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...THEREBY FOCUSING
MOST OF ITS ASSOCIATED MOISTURE ALONG NORTH AND EAST FACING SLOPES
AND COASTS. AFTER THE FRONT DISSIPATES...LIGHT TO MODERATE NORTHEAST
TO NORTH WINDS WILL PREVAIL INTO NEXT WEEK...DELIVERING BRIEF
WINDWARD SHOWERS...MAINLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LIGHT SYNOPTIC SCALE WINDS ALLOWED SEA BREEZES TO DRIVE CLOUD...AND
TO A LESSER DEGREE...SHOWER FORMATION OVER MOST ISLAND AREAS TODAY.
W/SW STEERING WINDS KEPT SOME LEEWARD LOCALES UNDER FAIRLY SUNNY
SKIES...AND ALSO PUSHED THE CLOUDINESS OVER NEAR SHORE WINDWARD
WATERS. RELATIVELY LOW PWAT VALUES NEAR ONE INCH AND A SUBSIDENCE
INVERSION NEAR 7 KFT HELPED TO LIMIT THE COVERAGE AND INTENSITY OF
THE AFTERNOON SHOWERS. THE EXPECTATION IS THAT LOW CLOUDS AND
ISOLATED SHOWERS...WHERE THEY EXIST...WILL GRADUALLY DIMINISH
THROUGH THE EVENING AS THE LIGHT WINDS ALLOW LAND BREEZES TO CLEAR
ISLAND SKIES. THE LIGHT WINDS ARE A RESULT OF A BREAK IN THE SURFACE
RIDGE TO THE N OF THE ISLANDS...WITH THE BREAK BEING CAUSED BY AN
APPROACHING FRONT...NOW ABOUT 275 MILES NW OF KAUAI. IN RESPONSE...
SURFACE PRESSURES IN THE ISLANDS HAVE DROPPED A HEARTY 4 TO 5 MB
OVER THE PAST 24 HOURS.

WHILE A GENERAL CLEARING TREND IS EXPECTED OVERNIGHT...WEAK
CONVERGENCE IN ADVANCE OF THE FRONT...AND GRAVITY WAVES PROPAGATING
THROUGH THE AREA...COULD SUPPORT CLOUD AND SHOWER DEVELOPMENT OVER
NEAR SHORE WATERS THAT COULD POTENTIALLY SNEAK ASHORE. WINDS ARE
SUFFICIENTLY VARIABLE TO LIMIT THE ADVECTION OF VOG FROM THE BIG
ISLAND OVER THE SMALLER ISLANDS...AND THE FORECAST HAS BEEN MODIFIED
TO REMOVE ITS MENTION...EXCEPT ON THE BIG ISLAND AND SURROUNDING
WATERS.

THE COLD FRONT IS MOVING SE TOWARD THE ISLANDS...AND THE DEVELOPMENT
OF A WEAK LOW ALONG THE FRONT ABOUT 550 MILES N OF THE ISLANDS WILL
HELP PROVIDE AN ADDITIONAL SOUTHWARD PUSH TO THE BOUNDARY...ALLOWING
IT TO MAKE A SOMEWHAT UNSEASONABLE TREK DOWN THE ENTIRE CHAIN.
LATEST GUIDANCE INDICATES THE FRONT WILL MOVE OVER KAUAI MID-MORNING
FRIDAY...REACHING OAHU IN THE LATE AFTERNOON FRIDAY...THEN SLOWING
AS IT SPREADS TO MAUI COUNTY THROUGH EARLY SATURDAY...AND THE BIG
ISLAND SATURDAY NIGHT...WHERE IT IS EXPECTED TO DISSIPATE. WITH WEAK
W/NW WINDS NEAR THE FRONT QUICKLY VEERING TO THE N/NE...MOST OF THE
MOISTURE ASSOCIATED WITH THE FRONT WILL FOCUS ALONG N AND E FACING
SLOPES AND COASTS. MAIN DYNAMICS ASSOCIATED WITH THIS SYSTEM WILL
STAY N OF THE STATE...THUS WIDESPREAD...OR HEAVY...RAINFALL IS NOT
EXPECTED.

THE LOW THAT HELPS TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER TO THE NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...AS HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS JUXTAPOSITION
OF FEATURES WILL LEAD TO UNSEASONABLE N/NE WINDS FOR THE BULK OF THE
FORECAST PERIOD...ALTHOUGH SPEEDS WILL BE LIGHT TO LOCALLY MODERATE.
AS THE LOW MAKES A JOG TO THE S EARLY NEXT WEEK...WINDS MAY BECOME
LIGHT ENOUGH TO ALLOW ISLAND-SCALE LAND/SEA BREEZES TO DOMINATE THE
ISLAND WEATHER PATTERN. OTHERWISE...SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LINGERING LOW WILL FUEL A FEW SHOWERS THAT WILL
CONTINUE TO FAVOR N AND E FACING SLOPES...BUT THE ATMOSPHERE WILL
REMAIN RELATIVELY STABLE THROUGH THE PERIOD. THE LOW WILL EXIT TO
THE NE BY THE SECOND HALF OF THE WEEK...AND LIGHT TO MODERATE TRADE
WINDS ARE EXPECTED THEN.

&&

.AVIATION...
CLOUDS AND SHOWERS ARE GREATEST ACROSS INTERIOR AND NORTHEAST TO
EAST SECTIONS OF THE ISLANDS...HAVING FLARED UP DURING THE AFTERNOON
ALONG WIDESPREAD SEA BREEZES. CONDITIONS WILL BE PRIMARILY VFR...
WITH OCCASIONAL MVFR CEILINGS AND VISIBILITIES IN SHOWERS. THESE
SHOWERS HAVE REMAINED TRANSIENT RATHER THAN ANCHORED OVER THE
TERRAIN...AND SO FAR A MOUNTAIN OBSCURATION AIRMET IS NOT
ANTICIPATED. WHILE THE SHOWERS OVER THE INTERIOR OF THE ISLANDS
WILL WEAKEN WITH SUNSET...ADDITIONAL ACTIVE SHOWERS ARE LOCATED FROM
SOUTHWEST OF KAUAI TO WEST OF THE BIG ISLAND. THESE CLOUDS AND
SHOWERS MAY STICK AROUND MORE TONIGHT THAN LAST NIGHT DUE TO
CONVERGENCE AHEAD OF THE APPROACHING FRONT...BUT PREDOMINANT VFR
CONDITIONS ARE STILL EXPECTED.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
ELEVATED SURF ALONG S FACING SHORES INTO THE MIDDLE OF NEXT WEEK.
SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS FOR THE
BULK OF THE TIME...BUT OVERLAPPING SWELLS SUNDAY/MONDAY COULD BRING
ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE OF SMALL
SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY
NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 220131
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
330 PM HST THU MAY 21 2015

.SYNOPSIS...
LIGHT AND VARIABLE WINDS WILL ALLOW CLOUDS AND A FEW SHOWERS TO
LINGER INTO THIS EVENING...AND THEN GRADUALLY DISSIPATE OVERNIGHT. A
WEAK FRONT...CURRENTLY NORTH OF THE ISLANDS...WILL MOVE OVER KAUAI
FRIDAY MORNING...AND THEN MOVE DOWN THE ISLAND CHAIN TO OAHU AND
MAUI COUNTY FROM LATE FRIDAY INTO SATURDAY. THE FRONT WILL
DISSIPATE NEAR THE BIG ISLAND SATURDAY NIGHT. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...THEREBY FOCUSING
MOST OF ITS ASSOCIATED MOISTURE ALONG NORTH AND EAST FACING SLOPES
AND COASTS. AFTER THE FRONT DISSIPATES...LIGHT TO MODERATE NORTHEAST
TO NORTH WINDS WILL PREVAIL INTO NEXT WEEK...DELIVERING BRIEF
WINDWARD SHOWERS...MAINLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LIGHT SYNOPTIC SCALE WINDS ALLOWED SEA BREEZES TO DRIVE CLOUD...AND
TO A LESSER DEGREE...SHOWER FORMATION OVER MOST ISLAND AREAS TODAY.
W/SW STEERING WINDS KEPT SOME LEEWARD LOCALES UNDER FAIRLY SUNNY
SKIES...AND ALSO PUSHED THE CLOUDINESS OVER NEAR SHORE WINDWARD
WATERS. RELATIVELY LOW PWAT VALUES NEAR ONE INCH AND A SUBSIDENCE
INVERSION NEAR 7 KFT HELPED TO LIMIT THE COVERAGE AND INTENSITY OF
THE AFTERNOON SHOWERS. THE EXPECTATION IS THAT LOW CLOUDS AND
ISOLATED SHOWERS...WHERE THEY EXIST...WILL GRADUALLY DIMINISH
THROUGH THE EVENING AS THE LIGHT WINDS ALLOW LAND BREEZES TO CLEAR
ISLAND SKIES. THE LIGHT WINDS ARE A RESULT OF A BREAK IN THE SURFACE
RIDGE TO THE N OF THE ISLANDS...WITH THE BREAK BEING CAUSED BY AN
APPROACHING FRONT...NOW ABOUT 275 MILES NW OF KAUAI. IN RESPONSE...
SURFACE PRESSURES IN THE ISLANDS HAVE DROPPED A HEARTY 4 TO 5 MB
OVER THE PAST 24 HOURS.

WHILE A GENERAL CLEARING TREND IS EXPECTED OVERNIGHT...WEAK
CONVERGENCE IN ADVANCE OF THE FRONT...AND GRAVITY WAVES PROPAGATING
THROUGH THE AREA...COULD SUPPORT CLOUD AND SHOWER DEVELOPMENT OVER
NEAR SHORE WATERS THAT COULD POTENTIALLY SNEAK ASHORE. WINDS ARE
SUFFICIENTLY VARIABLE TO LIMIT THE ADVECTION OF VOG FROM THE BIG
ISLAND OVER THE SMALLER ISLANDS...AND THE FORECAST HAS BEEN MODIFIED
TO REMOVE ITS MENTION...EXCEPT ON THE BIG ISLAND AND SURROUNDING
WATERS.

THE COLD FRONT IS MOVING SE TOWARD THE ISLANDS...AND THE DEVELOPMENT
OF A WEAK LOW ALONG THE FRONT ABOUT 550 MILES N OF THE ISLANDS WILL
HELP PROVIDE AN ADDITIONAL SOUTHWARD PUSH TO THE BOUNDARY...ALLOWING
IT TO MAKE A SOMEWHAT UNSEASONABLE TREK DOWN THE ENTIRE CHAIN.
LATEST GUIDANCE INDICATES THE FRONT WILL MOVE OVER KAUAI MID-MORNING
FRIDAY...REACHING OAHU IN THE LATE AFTERNOON FRIDAY...THEN SLOWING
AS IT SPREADS TO MAUI COUNTY THROUGH EARLY SATURDAY...AND THE BIG
ISLAND SATURDAY NIGHT...WHERE IT IS EXPECTED TO DISSIPATE. WITH WEAK
W/NW WINDS NEAR THE FRONT QUICKLY VEERING TO THE N/NE...MOST OF THE
MOISTURE ASSOCIATED WITH THE FRONT WILL FOCUS ALONG N AND E FACING
SLOPES AND COASTS. MAIN DYNAMICS ASSOCIATED WITH THIS SYSTEM WILL
STAY N OF THE STATE...THUS WIDESPREAD...OR HEAVY...RAINFALL IS NOT
EXPECTED.

THE LOW THAT HELPS TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER TO THE NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...AS HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS JUXTAPOSITION
OF FEATURES WILL LEAD TO UNSEASONABLE N/NE WINDS FOR THE BULK OF THE
FORECAST PERIOD...ALTHOUGH SPEEDS WILL BE LIGHT TO LOCALLY MODERATE.
AS THE LOW MAKES A JOG TO THE S EARLY NEXT WEEK...WINDS MAY BECOME
LIGHT ENOUGH TO ALLOW ISLAND-SCALE LAND/SEA BREEZES TO DOMINATE THE
ISLAND WEATHER PATTERN. OTHERWISE...SHALLOW BANDS OF MOISTURE
ROTATING AROUND THE LINGERING LOW WILL FUEL A FEW SHOWERS THAT WILL
CONTINUE TO FAVOR N AND E FACING SLOPES...BUT THE ATMOSPHERE WILL
REMAIN RELATIVELY STABLE THROUGH THE PERIOD. THE LOW WILL EXIT TO
THE NE BY THE SECOND HALF OF THE WEEK...AND LIGHT TO MODERATE TRADE
WINDS ARE EXPECTED THEN.

&&

.AVIATION...
CLOUDS AND SHOWERS ARE GREATEST ACROSS INTERIOR AND NORTHEAST TO
EAST SECTIONS OF THE ISLANDS...HAVING FLARED UP DURING THE AFTERNOON
ALONG WIDESPREAD SEA BREEZES. CONDITIONS WILL BE PRIMARILY VFR...
WITH OCCASIONAL MVFR CEILINGS AND VISIBILITIES IN SHOWERS. THESE
SHOWERS HAVE REMAINED TRANSIENT RATHER THAN ANCHORED OVER THE
TERRAIN...AND SO FAR A MOUNTAIN OBSCURATION AIRMET IS NOT
ANTICIPATED. WHILE THE SHOWERS OVER THE INTERIOR OF THE ISLANDS
WILL WEAKEN WITH SUNSET...ADDITIONAL ACTIVE SHOWERS ARE LOCATED FROM
SOUTHWEST OF KAUAI TO WEST OF THE BIG ISLAND. THESE CLOUDS AND
SHOWERS MAY STICK AROUND MORE TONIGHT THAN LAST NIGHT DUE TO
CONVERGENCE AHEAD OF THE APPROACHING FRONT...BUT PREDOMINANT VFR
CONDITIONS ARE STILL EXPECTED.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
ELEVATED SURF ALONG S FACING SHORES INTO THE MIDDLE OF NEXT WEEK.
SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS FOR THE
BULK OF THE TIME...BUT OVERLAPPING SWELLS SUNDAY/MONDAY COULD BRING
ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE OF SMALL
SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY
NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 212014
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1015 AM HST THU MAY 21 2015

.SYNOPSIS...
LIGHT AND VARIABLE WINDS WILL ALLOW CLOUDS AND A FEW SHOWERS TO
DEVELOP OVER THE ISLANDS THIS AFTERNOON...LINGER INTO THIS EVENING...
AND THEN GRADUALLY DISSIPATE OVERNIGHT. A WEAK FRONT WILL MOVE OVER
KAUAI FRIDAY MORNING...AND THEN MOVE DOWN THE ISLAND CHAIN TO OAHU
AND MAUI COUNTY FROM LATE FRIDAY INTO SATURDAY. THE FRONT WILL
DISSIPATE NEAR THE BIG ISLAND SATURDAY NIGHT. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...THEREBY FOCUSING
MOST OF ITS ASSOCIATED MOISTURE ALONG WINDWARD AND NORTH FACING
SLOPES AND COASTS. AFTER THE FRONT DISSIPATES...LIGHT TO MODERATE
NORTHEAST TO NORTH WINDS WILL PREVAIL INTO NEXT WEEK...DELIVERING
BRIEF WINDWARD SHOWERS...MAINLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LIGHT SYNOPTIC SCALE WINDS ALLOWED LAND BREEZES TO CLEAR SKIES OVER
THE ISLANDS OVERNIGHT AND THIS MORNING...WITH ABUNDANT SUNSHINE
OBSERVED STATEWIDE. HOWEVER...LOW CLOUDS ARE ALREADY INCREASING IN
COVERAGE ALONG THE LOWER SLOPES OF THE BIG ISLAND...AS SEA BREEZES
BEGIN TO CONVERGE. THE EXPECTATION IS THAT LOW CLOUDS WILL INCREASE
OVER ALL ISLANDS THROUGH MID-AFTERNOON...WITH A FEW SHOWERS
DEVELOPING...BUT A SUBSIDENCE INVERSION BASED BETWEEN 6 AND 8 KFT
SHOULD LIMIT THEIR VIGOR. WINDS SHOULD REMAIN SUFFICIENTLY LIGHT
OVERNIGHT TO ALLOW LAND BREEZES TO CLEAR SKIES OVER THE ISLANDS.
HAZE FROM THE BIG ISLAND MAY SPREAD ACROSS THE SMALLER ISLANDS UNDER
THE LIGHT S SYNOPTIC WINDS TONIGHT INTO FRIDAY.

THE LIGHT WINDS ARE DUE TO A BREAK IN THE RIDGE N OF THE ISLANDS...
WITH THE BREAK ASSOCIATED WITH AN APPROACHING COLD FRONT THAT IS
CURRENTLY ABOUT 400 MILES NW OF KAUAI. THE COLD FRONT IS MOVING SE
TOWARD THE ISLANDS...AND THE DEVELOPMENT OF A WEAK LOW ABOUT 550
MILES N OF THE ISLANDS IS EXPECTED TO HELP PROVIDE ADDITIONAL
SOUTHWARD PUSH TO THE FRONT...ALLOWING IT TO MOVE DOWN THE ENTIRE
ISLAND CHAIN...WHICH IS A LITTLE UNSEASONABLE. LATEST GUIDANCE
INDICATES THE FRONT WILL MOVE OVER KAUAI MID-MORNING FRIDAY...
REACHING OAHU IN THE AFTERNOON...SPREADING TO MAUI COUNTY IN THE
EVENING...AND THEN DISSIPATING NEAR THE BIG ISLAND SATURDAY NIGHT
AND EARLY SUNDAY. WITH WEAK W/NW WINDS NEAR THE FRONT QUICKLY
VEERING TO THE N/NE...MOST OF THE MOISTURE ASSOCIATED WITH THE FRONT
WILL FOCUS ALONG N AND E FACING SLOPES AND COASTS. MAIN DYNAMICS
ASSOCIATED WITH THIS SYSTEM WILL STAY N OF THE STATE...THUS
WIDESPREAD...OR HEAVY...RAINFALL IS NOT EXPECTED.

THE LOW THAT HELPS TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER TO THE NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...AS HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS JUXTAPOSITION
WILL LEAD TO UNSEASONABLE N/NE WINDS FOR THE BULK OF THE FORECAST
PERIOD...ALTHOUGH SPEEDS WILL BE LIGHT TO LOCALLY MODERATE. WINDS
MAY BE LIGHT ENOUGH MONDAY/TUESDAY TO ALLOW ISLAND-SCALE LAND/SEA
BREEZES TO DOMINATE THE ISLAND WEATHER PATTERN. OTHERWISE...WEAK
BANDS OF MOISTURE ROTATING AROUND THE LINGERING LOW WILL FUEL A FEW
SHOWERS THAT WILL CONTINUE TO FAVOR N AND E FACING SLOPES...BUT THE
ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH THE PERIOD. THE LOW
WILL EXIT TO THE NE BY THE SECOND HALF OF THE WEEK...AND LIGHT TO
MODERATE TRADE WINDS ARE EXPECTED THEN.

&&

.AVIATION...
CONDITIONS WILL BE PRIMARILY VFR. WIDESPREAD ONSHORE SEA BREEZES
WILL LEAD TO AFTERNOON BUILDUPS OF CLOUDS AND SHOWERS. OCCASIONAL
MVFR CONDITIONS ARE EXPECTED IN SHOWERS...MAINLY ACROSS INTERIOR AND
NORTHWESTERN SECTIONS OF THE ISLANDS. SHOWERS WILL WEAKEN WITH
SUNSET THIS EVENING...BUT CLOUDS MAY STICK AROUND MORE TONIGHT THAN
LAST NIGHT DUE TO CONVERGENCE AHEAD OF THE APPROACHING FRONT.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
ELEVATED SURF ALONG S FACING SHORES INTO THE MIDDLE OF NEXT WEEK.
SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS FOR THE
BULK OF THE TIME...BUT A PEAK ON SUNDAY/MONDAY COULD BRING ADVISORY
LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE OF SMALL SWELLS FROM
THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT WEEK...
WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 212014
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1015 AM HST THU MAY 21 2015

.SYNOPSIS...
LIGHT AND VARIABLE WINDS WILL ALLOW CLOUDS AND A FEW SHOWERS TO
DEVELOP OVER THE ISLANDS THIS AFTERNOON...LINGER INTO THIS EVENING...
AND THEN GRADUALLY DISSIPATE OVERNIGHT. A WEAK FRONT WILL MOVE OVER
KAUAI FRIDAY MORNING...AND THEN MOVE DOWN THE ISLAND CHAIN TO OAHU
AND MAUI COUNTY FROM LATE FRIDAY INTO SATURDAY. THE FRONT WILL
DISSIPATE NEAR THE BIG ISLAND SATURDAY NIGHT. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...THEREBY FOCUSING
MOST OF ITS ASSOCIATED MOISTURE ALONG WINDWARD AND NORTH FACING
SLOPES AND COASTS. AFTER THE FRONT DISSIPATES...LIGHT TO MODERATE
NORTHEAST TO NORTH WINDS WILL PREVAIL INTO NEXT WEEK...DELIVERING
BRIEF WINDWARD SHOWERS...MAINLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LIGHT SYNOPTIC SCALE WINDS ALLOWED LAND BREEZES TO CLEAR SKIES OVER
THE ISLANDS OVERNIGHT AND THIS MORNING...WITH ABUNDANT SUNSHINE
OBSERVED STATEWIDE. HOWEVER...LOW CLOUDS ARE ALREADY INCREASING IN
COVERAGE ALONG THE LOWER SLOPES OF THE BIG ISLAND...AS SEA BREEZES
BEGIN TO CONVERGE. THE EXPECTATION IS THAT LOW CLOUDS WILL INCREASE
OVER ALL ISLANDS THROUGH MID-AFTERNOON...WITH A FEW SHOWERS
DEVELOPING...BUT A SUBSIDENCE INVERSION BASED BETWEEN 6 AND 8 KFT
SHOULD LIMIT THEIR VIGOR. WINDS SHOULD REMAIN SUFFICIENTLY LIGHT
OVERNIGHT TO ALLOW LAND BREEZES TO CLEAR SKIES OVER THE ISLANDS.
HAZE FROM THE BIG ISLAND MAY SPREAD ACROSS THE SMALLER ISLANDS UNDER
THE LIGHT S SYNOPTIC WINDS TONIGHT INTO FRIDAY.

THE LIGHT WINDS ARE DUE TO A BREAK IN THE RIDGE N OF THE ISLANDS...
WITH THE BREAK ASSOCIATED WITH AN APPROACHING COLD FRONT THAT IS
CURRENTLY ABOUT 400 MILES NW OF KAUAI. THE COLD FRONT IS MOVING SE
TOWARD THE ISLANDS...AND THE DEVELOPMENT OF A WEAK LOW ABOUT 550
MILES N OF THE ISLANDS IS EXPECTED TO HELP PROVIDE ADDITIONAL
SOUTHWARD PUSH TO THE FRONT...ALLOWING IT TO MOVE DOWN THE ENTIRE
ISLAND CHAIN...WHICH IS A LITTLE UNSEASONABLE. LATEST GUIDANCE
INDICATES THE FRONT WILL MOVE OVER KAUAI MID-MORNING FRIDAY...
REACHING OAHU IN THE AFTERNOON...SPREADING TO MAUI COUNTY IN THE
EVENING...AND THEN DISSIPATING NEAR THE BIG ISLAND SATURDAY NIGHT
AND EARLY SUNDAY. WITH WEAK W/NW WINDS NEAR THE FRONT QUICKLY
VEERING TO THE N/NE...MOST OF THE MOISTURE ASSOCIATED WITH THE FRONT
WILL FOCUS ALONG N AND E FACING SLOPES AND COASTS. MAIN DYNAMICS
ASSOCIATED WITH THIS SYSTEM WILL STAY N OF THE STATE...THUS
WIDESPREAD...OR HEAVY...RAINFALL IS NOT EXPECTED.

THE LOW THAT HELPS TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER TO THE NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...AS HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS JUXTAPOSITION
WILL LEAD TO UNSEASONABLE N/NE WINDS FOR THE BULK OF THE FORECAST
PERIOD...ALTHOUGH SPEEDS WILL BE LIGHT TO LOCALLY MODERATE. WINDS
MAY BE LIGHT ENOUGH MONDAY/TUESDAY TO ALLOW ISLAND-SCALE LAND/SEA
BREEZES TO DOMINATE THE ISLAND WEATHER PATTERN. OTHERWISE...WEAK
BANDS OF MOISTURE ROTATING AROUND THE LINGERING LOW WILL FUEL A FEW
SHOWERS THAT WILL CONTINUE TO FAVOR N AND E FACING SLOPES...BUT THE
ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH THE PERIOD. THE LOW
WILL EXIT TO THE NE BY THE SECOND HALF OF THE WEEK...AND LIGHT TO
MODERATE TRADE WINDS ARE EXPECTED THEN.

&&

.AVIATION...
CONDITIONS WILL BE PRIMARILY VFR. WIDESPREAD ONSHORE SEA BREEZES
WILL LEAD TO AFTERNOON BUILDUPS OF CLOUDS AND SHOWERS. OCCASIONAL
MVFR CONDITIONS ARE EXPECTED IN SHOWERS...MAINLY ACROSS INTERIOR AND
NORTHWESTERN SECTIONS OF THE ISLANDS. SHOWERS WILL WEAKEN WITH
SUNSET THIS EVENING...BUT CLOUDS MAY STICK AROUND MORE TONIGHT THAN
LAST NIGHT DUE TO CONVERGENCE AHEAD OF THE APPROACHING FRONT.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
ELEVATED SURF ALONG S FACING SHORES INTO THE MIDDLE OF NEXT WEEK.
SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS FOR THE
BULK OF THE TIME...BUT A PEAK ON SUNDAY/MONDAY COULD BRING ADVISORY
LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE OF SMALL SWELLS FROM
THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT WEEK...
WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 212014
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1015 AM HST THU MAY 21 2015

.SYNOPSIS...
LIGHT AND VARIABLE WINDS WILL ALLOW CLOUDS AND A FEW SHOWERS TO
DEVELOP OVER THE ISLANDS THIS AFTERNOON...LINGER INTO THIS EVENING...
AND THEN GRADUALLY DISSIPATE OVERNIGHT. A WEAK FRONT WILL MOVE OVER
KAUAI FRIDAY MORNING...AND THEN MOVE DOWN THE ISLAND CHAIN TO OAHU
AND MAUI COUNTY FROM LATE FRIDAY INTO SATURDAY. THE FRONT WILL
DISSIPATE NEAR THE BIG ISLAND SATURDAY NIGHT. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...THEREBY FOCUSING
MOST OF ITS ASSOCIATED MOISTURE ALONG WINDWARD AND NORTH FACING
SLOPES AND COASTS. AFTER THE FRONT DISSIPATES...LIGHT TO MODERATE
NORTHEAST TO NORTH WINDS WILL PREVAIL INTO NEXT WEEK...DELIVERING
BRIEF WINDWARD SHOWERS...MAINLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LIGHT SYNOPTIC SCALE WINDS ALLOWED LAND BREEZES TO CLEAR SKIES OVER
THE ISLANDS OVERNIGHT AND THIS MORNING...WITH ABUNDANT SUNSHINE
OBSERVED STATEWIDE. HOWEVER...LOW CLOUDS ARE ALREADY INCREASING IN
COVERAGE ALONG THE LOWER SLOPES OF THE BIG ISLAND...AS SEA BREEZES
BEGIN TO CONVERGE. THE EXPECTATION IS THAT LOW CLOUDS WILL INCREASE
OVER ALL ISLANDS THROUGH MID-AFTERNOON...WITH A FEW SHOWERS
DEVELOPING...BUT A SUBSIDENCE INVERSION BASED BETWEEN 6 AND 8 KFT
SHOULD LIMIT THEIR VIGOR. WINDS SHOULD REMAIN SUFFICIENTLY LIGHT
OVERNIGHT TO ALLOW LAND BREEZES TO CLEAR SKIES OVER THE ISLANDS.
HAZE FROM THE BIG ISLAND MAY SPREAD ACROSS THE SMALLER ISLANDS UNDER
THE LIGHT S SYNOPTIC WINDS TONIGHT INTO FRIDAY.

THE LIGHT WINDS ARE DUE TO A BREAK IN THE RIDGE N OF THE ISLANDS...
WITH THE BREAK ASSOCIATED WITH AN APPROACHING COLD FRONT THAT IS
CURRENTLY ABOUT 400 MILES NW OF KAUAI. THE COLD FRONT IS MOVING SE
TOWARD THE ISLANDS...AND THE DEVELOPMENT OF A WEAK LOW ABOUT 550
MILES N OF THE ISLANDS IS EXPECTED TO HELP PROVIDE ADDITIONAL
SOUTHWARD PUSH TO THE FRONT...ALLOWING IT TO MOVE DOWN THE ENTIRE
ISLAND CHAIN...WHICH IS A LITTLE UNSEASONABLE. LATEST GUIDANCE
INDICATES THE FRONT WILL MOVE OVER KAUAI MID-MORNING FRIDAY...
REACHING OAHU IN THE AFTERNOON...SPREADING TO MAUI COUNTY IN THE
EVENING...AND THEN DISSIPATING NEAR THE BIG ISLAND SATURDAY NIGHT
AND EARLY SUNDAY. WITH WEAK W/NW WINDS NEAR THE FRONT QUICKLY
VEERING TO THE N/NE...MOST OF THE MOISTURE ASSOCIATED WITH THE FRONT
WILL FOCUS ALONG N AND E FACING SLOPES AND COASTS. MAIN DYNAMICS
ASSOCIATED WITH THIS SYSTEM WILL STAY N OF THE STATE...THUS
WIDESPREAD...OR HEAVY...RAINFALL IS NOT EXPECTED.

THE LOW THAT HELPS TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER TO THE NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...AS HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS JUXTAPOSITION
WILL LEAD TO UNSEASONABLE N/NE WINDS FOR THE BULK OF THE FORECAST
PERIOD...ALTHOUGH SPEEDS WILL BE LIGHT TO LOCALLY MODERATE. WINDS
MAY BE LIGHT ENOUGH MONDAY/TUESDAY TO ALLOW ISLAND-SCALE LAND/SEA
BREEZES TO DOMINATE THE ISLAND WEATHER PATTERN. OTHERWISE...WEAK
BANDS OF MOISTURE ROTATING AROUND THE LINGERING LOW WILL FUEL A FEW
SHOWERS THAT WILL CONTINUE TO FAVOR N AND E FACING SLOPES...BUT THE
ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH THE PERIOD. THE LOW
WILL EXIT TO THE NE BY THE SECOND HALF OF THE WEEK...AND LIGHT TO
MODERATE TRADE WINDS ARE EXPECTED THEN.

&&

.AVIATION...
CONDITIONS WILL BE PRIMARILY VFR. WIDESPREAD ONSHORE SEA BREEZES
WILL LEAD TO AFTERNOON BUILDUPS OF CLOUDS AND SHOWERS. OCCASIONAL
MVFR CONDITIONS ARE EXPECTED IN SHOWERS...MAINLY ACROSS INTERIOR AND
NORTHWESTERN SECTIONS OF THE ISLANDS. SHOWERS WILL WEAKEN WITH
SUNSET THIS EVENING...BUT CLOUDS MAY STICK AROUND MORE TONIGHT THAN
LAST NIGHT DUE TO CONVERGENCE AHEAD OF THE APPROACHING FRONT.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
ELEVATED SURF ALONG S FACING SHORES INTO THE MIDDLE OF NEXT WEEK.
SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS FOR THE
BULK OF THE TIME...BUT A PEAK ON SUNDAY/MONDAY COULD BRING ADVISORY
LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE OF SMALL SWELLS FROM
THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT WEEK...
WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 212014
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1015 AM HST THU MAY 21 2015

.SYNOPSIS...
LIGHT AND VARIABLE WINDS WILL ALLOW CLOUDS AND A FEW SHOWERS TO
DEVELOP OVER THE ISLANDS THIS AFTERNOON...LINGER INTO THIS EVENING...
AND THEN GRADUALLY DISSIPATE OVERNIGHT. A WEAK FRONT WILL MOVE OVER
KAUAI FRIDAY MORNING...AND THEN MOVE DOWN THE ISLAND CHAIN TO OAHU
AND MAUI COUNTY FROM LATE FRIDAY INTO SATURDAY. THE FRONT WILL
DISSIPATE NEAR THE BIG ISLAND SATURDAY NIGHT. A BRIEF PERIOD OF
BREEZY NORTHEAST WINDS WILL ACCOMPANY THE FRONT...THEREBY FOCUSING
MOST OF ITS ASSOCIATED MOISTURE ALONG WINDWARD AND NORTH FACING
SLOPES AND COASTS. AFTER THE FRONT DISSIPATES...LIGHT TO MODERATE
NORTHEAST TO NORTH WINDS WILL PREVAIL INTO NEXT WEEK...DELIVERING
BRIEF WINDWARD SHOWERS...MAINLY DURING NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LIGHT SYNOPTIC SCALE WINDS ALLOWED LAND BREEZES TO CLEAR SKIES OVER
THE ISLANDS OVERNIGHT AND THIS MORNING...WITH ABUNDANT SUNSHINE
OBSERVED STATEWIDE. HOWEVER...LOW CLOUDS ARE ALREADY INCREASING IN
COVERAGE ALONG THE LOWER SLOPES OF THE BIG ISLAND...AS SEA BREEZES
BEGIN TO CONVERGE. THE EXPECTATION IS THAT LOW CLOUDS WILL INCREASE
OVER ALL ISLANDS THROUGH MID-AFTERNOON...WITH A FEW SHOWERS
DEVELOPING...BUT A SUBSIDENCE INVERSION BASED BETWEEN 6 AND 8 KFT
SHOULD LIMIT THEIR VIGOR. WINDS SHOULD REMAIN SUFFICIENTLY LIGHT
OVERNIGHT TO ALLOW LAND BREEZES TO CLEAR SKIES OVER THE ISLANDS.
HAZE FROM THE BIG ISLAND MAY SPREAD ACROSS THE SMALLER ISLANDS UNDER
THE LIGHT S SYNOPTIC WINDS TONIGHT INTO FRIDAY.

THE LIGHT WINDS ARE DUE TO A BREAK IN THE RIDGE N OF THE ISLANDS...
WITH THE BREAK ASSOCIATED WITH AN APPROACHING COLD FRONT THAT IS
CURRENTLY ABOUT 400 MILES NW OF KAUAI. THE COLD FRONT IS MOVING SE
TOWARD THE ISLANDS...AND THE DEVELOPMENT OF A WEAK LOW ABOUT 550
MILES N OF THE ISLANDS IS EXPECTED TO HELP PROVIDE ADDITIONAL
SOUTHWARD PUSH TO THE FRONT...ALLOWING IT TO MOVE DOWN THE ENTIRE
ISLAND CHAIN...WHICH IS A LITTLE UNSEASONABLE. LATEST GUIDANCE
INDICATES THE FRONT WILL MOVE OVER KAUAI MID-MORNING FRIDAY...
REACHING OAHU IN THE AFTERNOON...SPREADING TO MAUI COUNTY IN THE
EVENING...AND THEN DISSIPATING NEAR THE BIG ISLAND SATURDAY NIGHT
AND EARLY SUNDAY. WITH WEAK W/NW WINDS NEAR THE FRONT QUICKLY
VEERING TO THE N/NE...MOST OF THE MOISTURE ASSOCIATED WITH THE FRONT
WILL FOCUS ALONG N AND E FACING SLOPES AND COASTS. MAIN DYNAMICS
ASSOCIATED WITH THIS SYSTEM WILL STAY N OF THE STATE...THUS
WIDESPREAD...OR HEAVY...RAINFALL IS NOT EXPECTED.

THE LOW THAT HELPS TO PUSH THE FRONT DOWN THE CHAIN IS FORECAST TO
LINGER TO THE NE OF THE ISLANDS THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...AS HIGH PRESSURE BUILDS NW OF THE ISLANDS. THIS JUXTAPOSITION
WILL LEAD TO UNSEASONABLE N/NE WINDS FOR THE BULK OF THE FORECAST
PERIOD...ALTHOUGH SPEEDS WILL BE LIGHT TO LOCALLY MODERATE. WINDS
MAY BE LIGHT ENOUGH MONDAY/TUESDAY TO ALLOW ISLAND-SCALE LAND/SEA
BREEZES TO DOMINATE THE ISLAND WEATHER PATTERN. OTHERWISE...WEAK
BANDS OF MOISTURE ROTATING AROUND THE LINGERING LOW WILL FUEL A FEW
SHOWERS THAT WILL CONTINUE TO FAVOR N AND E FACING SLOPES...BUT THE
ATMOSPHERE WILL REMAIN RELATIVELY STABLE THROUGH THE PERIOD. THE LOW
WILL EXIT TO THE NE BY THE SECOND HALF OF THE WEEK...AND LIGHT TO
MODERATE TRADE WINDS ARE EXPECTED THEN.

&&

.AVIATION...
CONDITIONS WILL BE PRIMARILY VFR. WIDESPREAD ONSHORE SEA BREEZES
WILL LEAD TO AFTERNOON BUILDUPS OF CLOUDS AND SHOWERS. OCCASIONAL
MVFR CONDITIONS ARE EXPECTED IN SHOWERS...MAINLY ACROSS INTERIOR AND
NORTHWESTERN SECTIONS OF THE ISLANDS. SHOWERS WILL WEAKEN WITH
SUNSET THIS EVENING...BUT CLOUDS MAY STICK AROUND MORE TONIGHT THAN
LAST NIGHT DUE TO CONVERGENCE AHEAD OF THE APPROACHING FRONT.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR
ALL WATERS INTO NEXT WEEK. AN EXTENDED RUN OF S SWELL...GENERATED BY
SEVERAL LOWS IN THE DEEP S PACIFIC OVER THE LAST WEEK...WILL BRING
ELEVATED SURF ALONG S FACING SHORES INTO THE MIDDLE OF NEXT WEEK.
SURF HEIGHTS ARE EXPECTED TO REMAIN BELOW ADVISORY LEVELS FOR THE
BULK OF THE TIME...BUT A PEAK ON SUNDAY/MONDAY COULD BRING ADVISORY
LEVEL SURF TO EXPOSED S FACING SHORES. A COUPLE OF SMALL SWELLS FROM
THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT WEEK...
WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 211401
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST THU MAY 21 2015

.SYNOPSIS...
WINDS WILL BE LIGHT AND VARIABLE WITH SEA BREEZES TODAY...AS A WEAK
FRONT APPROACHES THE ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI
EARLY FRIDAY...THEN DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN
THROUGH SATURDAY. THE FRONT WILL BRING A FEW SHOWERS...MAINLY TO
WINDWARD AND NORTH FACING SLOPES AND COASTS...AND A BRIEF SURGE OF
NORTHERLY TRADE WINDS. LIGHT TO MODERATE NORTHEAST TRADE WINDS WILL
PREVAIL EARLY PART OF NEXT WEEK...DELIVERING BRIEF WINDWARD SHOWERS
MAINLY NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LAND BREEZES HAVE DEVELOPED OVER THE ISLANDS EARLY THIS MORNING...AS
BACKGROUND SYNOPTIC WINDS HAVE BECOME LIGHT ACROSS THE STATE. AN
APPROACHING COLD FRONT ABOUT 450 MILES NORTHWEST OF KAUAI CONTINUES
TO ADVANCE SOUTHEAST...DISPLACING THE TRADE-WIND GENERATING SURFACE
HIGH FAR NORTHEAST OF THE STATE FURTHER AWAY FROM THE AREA. SOME
CLEARING DID OCCUR OVERNIGHT OVER THE ISLANDS...WITH LINGERING
CLOUDS REMAIN OVER PORTIONS OF COASTAL WATERS BRINGING SOME SHOWERS.
EARLY MORNING LIHUE AND HILO SOUNDINGS CONTINUE TO DEPICT A STABLE
AND RELATIVELY DRY AIR MASS IN THE ISLAND VICINITY. EXPECT RATHER
FAIR WEATHER TO PREVAIL ACROSS THE STATE THROUGH REST OF THE
MORNING.

A WEAK SURFACE RIDGE EXTENDING SOUTHWEST FROM THE AFOREMENTIONED
SURFACE HIGH WILL MOVE OVER THE ISLANDS LATER TODAY...AHEAD OF THE
APPROACHING COLD FRONT. SYNOPTIC WINDS WILL TURN MORE SOUTHEASTERLY
IN THE AREA BUT REMAIN LIGHT...ALLOWING ISLAND-SCALE LAND-SEA
BREEZES TO DEVELOP. MORNING LAND BREEZES WILL GIVE WAY TO SEA
BREEZES IN THE AFTERNOON. LOW CLOUDS WILL FORM OVER THE ISLANDS
LATER TODAY UNDER DAYTIME HEATING. SOME OF THESE CONVECTIVE CLOUDS
WILL PRODUCE SHOWERS BY THE AFTERNOON AND EVENING...THOUGH AIR MASS
WILL REMAIN STABLE. THUS LIMITED AMOUNTS OF RAINFALL ARE EXPECTED.
HAZE FROM THE BIG ISLAND MAY SPREAD ACROSS THE SMALLER ISLANDS UNDER
THE LIGHT SOUTHEASTERLY SYNOPTIC WINDS.

WINDS WILL REMAIN LIGHT SOUTHERLY OVER MOST OF THE STATE TONIGHT AS
THE SURFACE RIDGE CONTINUES TO SHIFT SOUTHEAST. WINDS MAY ACTUALLY
TURN NORTHWESTERLY AROUND KAUAI JUST AHEAD OF THE ARRIVAL OF THE
FRONT. LAND BREEZES WILL RETURN TO THE ISLANDS...WITH CLEARING
EXPECTED OVER MAUI COUNTY AS WELL AS BIG ISLAND. THERE MAY BE MORE
LINGERING LOW CLOUDS AFFECTING KAUAI AND OAHU TONIGHT.

LATEST MODEL SOLUTIONS NOW HAVE THE FRONT REACHING KAUAI EARLY
FRIDAY...THEN OAHU LATER ON FRIDAY...AND MAUI COUNTY AND THE BIG
ISLAND BY FRIDAY NIGHT INTO SATURDAY. MAIN DYNAMICS ASSOCIATED WITH
THIS SYSTEM WILL STAY NORTH OF THE STATE...THOUGH LOW CLOUDS
ASSOCIATED WITH THIS FRONT WILL SPREAD ACROSS THE ISLANDS...BRINGING
SOME SHOWERS. WINDS WILL SURGE BRIEFLY NORTHERLY AS THE FRONT
PASSES...THUS BRINGING MUCH OF THE MOISTURE TO THE WINDWARD SLOPES
AND COASTS.

A SURFACE HIGH PRESSURE FROM THE FAR NORTHWEST WILL ADVANCE
SOUTHEAST OVER THE WEEKEND INTO EARLY NEXT WEEK...BRINGING
NORTHEASTERLY TRADE WINDS TO THE AREA. LATEST MODEL SOLUTIONS HINT
ANOTHER WEAK SURFACE TROUGH MAY PASS JUST NORTHEAST OF THE ISLANDS
DURING THE EARLY PART OF NEXT WEEK. THIS WILL LEAD TO AN EASING OF
WINDS OVER THE ISLANDS ONCE AGAIN...ESPECIALLY FOR MAUI COUNTY AND
THE BIG ISLAND. LINGERING MOISTURE FROM THE DISSIPATED FRONT MAY
PERSIST IN THE ISLAND VICINITY AS WELL...PROVIDING SOME SHOWERS. A
RIDGE MAY EVENTUALLY ESTABLISH NORTH OF THE STATE LATER PART OF NEXT
WEEK...WITH MORE TYPICAL TRADE WIND WEATHER AND LIGHT TO MODERATE
TRADE WINDS RETURNING TO THE STATE.

&&

.AVIATION...
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT THE TERMINALS THIS
MORNING...BUT BRIEF MVFR CONDITIONS ARE POSSIBLE DUE TO LOW CEILINGS
AT PHLI AND PHJR DURING THIS AFTERNOON. NO AIRMET CONDITIONS ARE
ANTICIPATED TODAY...BUT THERE IS A POSSIBILITY OF MTN OBSCURATION ON
PARTS OF KAUAI OR OAHU THIS AFTERNOON.

LOW-LEVEL WINDS HAVE EASED OVERNIGHT DUE TO A WEAK SURFACE RIDGE
MOVING SOUTH TO A POSITION JUST NORTH OF KAUAI THIS MORNING. DUE TO
THESE RELATIVELY LIGHT BACKGROUND WINDS...LOCAL LAND BREEZE
CIRCULATIONS DOMINATE THE WEATHER OVER MOST ISLANDS EARLY THIS
MORNING.

BY THIS LATE THIS MORNING AND THIS AFTERNOON...THE LIGHT LOW-LEVEL
FLOW IS EXPECTED TO ALLOW LOCAL SEA BREEZE CIRCULATIONS TO DEVELOP
OVER EACH OF THE INDIVIDUAL ISLANDS. THESE SEA BREEZES WILL LIKELY
RESULT IN AFTERNOON CLOUDS AND ISOLATED SHOWERS...ESPECIALLY OVER
LEEWARD AND INTERIOR SECTIONS OF MOST ISLANDS.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT CRITERIA FOR ALL
WATERS INTO NEXT WEEK. THEREFORE NO MARINE ADVISORY IS EXPECTED.
AN EXTENDED RUN OF SOUTH SWELL WILL BRING ELEVATED SURF ALONG SOUTH
FACING SHORES BEGINNING LATER TODAY...WITH SURF HEIGHTS LIKELY
BELOW ADVISORY LEVELS THROUGH THE REST OF THE WEEK INTO NEXT.
HOWEVER...A PEAK OF SOUTH SWELL ON SUNDAY AND MONDAY COULD BRING
ADVISORY LEVEL SURF TO EXPOSED SOUTH FACING SHORES. A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND
EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...HUI
AVIATION...HOUSTON






000
FXHW60 PHFO 211401
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST THU MAY 21 2015

.SYNOPSIS...
WINDS WILL BE LIGHT AND VARIABLE WITH SEA BREEZES TODAY...AS A WEAK
FRONT APPROACHES THE ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI
EARLY FRIDAY...THEN DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN
THROUGH SATURDAY. THE FRONT WILL BRING A FEW SHOWERS...MAINLY TO
WINDWARD AND NORTH FACING SLOPES AND COASTS...AND A BRIEF SURGE OF
NORTHERLY TRADE WINDS. LIGHT TO MODERATE NORTHEAST TRADE WINDS WILL
PREVAIL EARLY PART OF NEXT WEEK...DELIVERING BRIEF WINDWARD SHOWERS
MAINLY NIGHTS AND MORNINGS.

&&

.DISCUSSION...
LAND BREEZES HAVE DEVELOPED OVER THE ISLANDS EARLY THIS MORNING...AS
BACKGROUND SYNOPTIC WINDS HAVE BECOME LIGHT ACROSS THE STATE. AN
APPROACHING COLD FRONT ABOUT 450 MILES NORTHWEST OF KAUAI CONTINUES
TO ADVANCE SOUTHEAST...DISPLACING THE TRADE-WIND GENERATING SURFACE
HIGH FAR NORTHEAST OF THE STATE FURTHER AWAY FROM THE AREA. SOME
CLEARING DID OCCUR OVERNIGHT OVER THE ISLANDS...WITH LINGERING
CLOUDS REMAIN OVER PORTIONS OF COASTAL WATERS BRINGING SOME SHOWERS.
EARLY MORNING LIHUE AND HILO SOUNDINGS CONTINUE TO DEPICT A STABLE
AND RELATIVELY DRY AIR MASS IN THE ISLAND VICINITY. EXPECT RATHER
FAIR WEATHER TO PREVAIL ACROSS THE STATE THROUGH REST OF THE
MORNING.

A WEAK SURFACE RIDGE EXTENDING SOUTHWEST FROM THE AFOREMENTIONED
SURFACE HIGH WILL MOVE OVER THE ISLANDS LATER TODAY...AHEAD OF THE
APPROACHING COLD FRONT. SYNOPTIC WINDS WILL TURN MORE SOUTHEASTERLY
IN THE AREA BUT REMAIN LIGHT...ALLOWING ISLAND-SCALE LAND-SEA
BREEZES TO DEVELOP. MORNING LAND BREEZES WILL GIVE WAY TO SEA
BREEZES IN THE AFTERNOON. LOW CLOUDS WILL FORM OVER THE ISLANDS
LATER TODAY UNDER DAYTIME HEATING. SOME OF THESE CONVECTIVE CLOUDS
WILL PRODUCE SHOWERS BY THE AFTERNOON AND EVENING...THOUGH AIR MASS
WILL REMAIN STABLE. THUS LIMITED AMOUNTS OF RAINFALL ARE EXPECTED.
HAZE FROM THE BIG ISLAND MAY SPREAD ACROSS THE SMALLER ISLANDS UNDER
THE LIGHT SOUTHEASTERLY SYNOPTIC WINDS.

WINDS WILL REMAIN LIGHT SOUTHERLY OVER MOST OF THE STATE TONIGHT AS
THE SURFACE RIDGE CONTINUES TO SHIFT SOUTHEAST. WINDS MAY ACTUALLY
TURN NORTHWESTERLY AROUND KAUAI JUST AHEAD OF THE ARRIVAL OF THE
FRONT. LAND BREEZES WILL RETURN TO THE ISLANDS...WITH CLEARING
EXPECTED OVER MAUI COUNTY AS WELL AS BIG ISLAND. THERE MAY BE MORE
LINGERING LOW CLOUDS AFFECTING KAUAI AND OAHU TONIGHT.

LATEST MODEL SOLUTIONS NOW HAVE THE FRONT REACHING KAUAI EARLY
FRIDAY...THEN OAHU LATER ON FRIDAY...AND MAUI COUNTY AND THE BIG
ISLAND BY FRIDAY NIGHT INTO SATURDAY. MAIN DYNAMICS ASSOCIATED WITH
THIS SYSTEM WILL STAY NORTH OF THE STATE...THOUGH LOW CLOUDS
ASSOCIATED WITH THIS FRONT WILL SPREAD ACROSS THE ISLANDS...BRINGING
SOME SHOWERS. WINDS WILL SURGE BRIEFLY NORTHERLY AS THE FRONT
PASSES...THUS BRINGING MUCH OF THE MOISTURE TO THE WINDWARD SLOPES
AND COASTS.

A SURFACE HIGH PRESSURE FROM THE FAR NORTHWEST WILL ADVANCE
SOUTHEAST OVER THE WEEKEND INTO EARLY NEXT WEEK...BRINGING
NORTHEASTERLY TRADE WINDS TO THE AREA. LATEST MODEL SOLUTIONS HINT
ANOTHER WEAK SURFACE TROUGH MAY PASS JUST NORTHEAST OF THE ISLANDS
DURING THE EARLY PART OF NEXT WEEK. THIS WILL LEAD TO AN EASING OF
WINDS OVER THE ISLANDS ONCE AGAIN...ESPECIALLY FOR MAUI COUNTY AND
THE BIG ISLAND. LINGERING MOISTURE FROM THE DISSIPATED FRONT MAY
PERSIST IN THE ISLAND VICINITY AS WELL...PROVIDING SOME SHOWERS. A
RIDGE MAY EVENTUALLY ESTABLISH NORTH OF THE STATE LATER PART OF NEXT
WEEK...WITH MORE TYPICAL TRADE WIND WEATHER AND LIGHT TO MODERATE
TRADE WINDS RETURNING TO THE STATE.

&&

.AVIATION...
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT THE TERMINALS THIS
MORNING...BUT BRIEF MVFR CONDITIONS ARE POSSIBLE DUE TO LOW CEILINGS
AT PHLI AND PHJR DURING THIS AFTERNOON. NO AIRMET CONDITIONS ARE
ANTICIPATED TODAY...BUT THERE IS A POSSIBILITY OF MTN OBSCURATION ON
PARTS OF KAUAI OR OAHU THIS AFTERNOON.

LOW-LEVEL WINDS HAVE EASED OVERNIGHT DUE TO A WEAK SURFACE RIDGE
MOVING SOUTH TO A POSITION JUST NORTH OF KAUAI THIS MORNING. DUE TO
THESE RELATIVELY LIGHT BACKGROUND WINDS...LOCAL LAND BREEZE
CIRCULATIONS DOMINATE THE WEATHER OVER MOST ISLANDS EARLY THIS
MORNING.

BY THIS LATE THIS MORNING AND THIS AFTERNOON...THE LIGHT LOW-LEVEL
FLOW IS EXPECTED TO ALLOW LOCAL SEA BREEZE CIRCULATIONS TO DEVELOP
OVER EACH OF THE INDIVIDUAL ISLANDS. THESE SEA BREEZES WILL LIKELY
RESULT IN AFTERNOON CLOUDS AND ISOLATED SHOWERS...ESPECIALLY OVER
LEEWARD AND INTERIOR SECTIONS OF MOST ISLANDS.

&&

.MARINE...
WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT CRITERIA FOR ALL
WATERS INTO NEXT WEEK. THEREFORE NO MARINE ADVISORY IS EXPECTED.
AN EXTENDED RUN OF SOUTH SWELL WILL BRING ELEVATED SURF ALONG SOUTH
FACING SHORES BEGINNING LATER TODAY...WITH SURF HEIGHTS LIKELY
BELOW ADVISORY LEVELS THROUGH THE REST OF THE WEEK INTO NEXT.
HOWEVER...A PEAK OF SOUTH SWELL ON SUNDAY AND MONDAY COULD BRING
ADVISORY LEVEL SURF TO EXPOSED SOUTH FACING SHORES. A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND
EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...HUI
AVIATION...HOUSTON







000
FXHW60 PHFO 210646
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST WED MAY 20 2015

.SYNOPSIS...
WINDS WILL BECOME LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT
APPROACHES THE ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON
FRIDAY...THEN DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH
SUNDAY. THE FRONT WILL BRING A FEW SHOWERS...MAINLY TO WINDWARD AND
NORTH FACING SLOPES AND COASTS...AND A BRIEF SURGE OF NORTHEASTERLY
TRADE WINDS. LIGHT TO MODERATE NORTHEAST TRADE WINDS WILL THEN
PREVAIL INTO THE MIDDLE OF NEXT WEEK...DELIVERING BRIEF WINDWARD
SHOWERS MAINLY NIGHTS AND MORNINGS.

&&

.DISCUSSION...
TRADE WINDS CONTINUE TO DIMINISH THIS EVENING...AS A COLD FRONT FAR
NORTHWEST OF THE ISLANDS ADVANCES SOUTHEAST. THE FRONT IS DISPLACING
THE TRADE-WIND GENERATING SURFACE HIGH FAR NORTHEAST OF THE STATE
FURTHER AWAY FROM THE AREA. AS THE WINDS WEAKEN...LOW CLOUDS IN THE
ISLAND VICINITY WILL LINGER. LAND BREEZES WILL SLOWLY DEVELOP UNDER
NIGHT TIME COOLING...AND SHOULD LEAD TO CLEARING SKIES OVER THE
ISLANDS OVERNIGHT.

A WEAK SURFACE RIDGE EXTENDING SOUTHWEST FROM THE AFOREMENTIONED
SURFACE HIGH WILL BE PUSHED OVER THE ISLANDS ON THURSDAY...AHEAD OF
THE APPROACHING COLD FRONT. WINDS WILL REMAIN LIGHT AND
VARIABLE...ALLOWING ISLAND-SCALE LAND AND SEA BREEZES TO DOMINATE
THE ISLAND WEATHER. HENCE MOSTLY CLEAR SKIES ARE EXPECTED OVER THE
ISLANDS THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING
OVER INTERIOR AND MAUKA AREAS IN THE AFTERNOON. FORECAST SOLUTIONS
INDICATE A STABLE AIR MASS WILL PERSIST IN THE ISLAND
VICINITY...THEREFORE SHOWERS WILL BE LIMITED.

THE RIDGE WILL SHIFT FURTHER SOUTHEAST OF THE ISLANDS BY THURSDAY
NIGHT...WHILE WINDS WILL REMAIN LIGHT SOUTHERLY OVER THE STATE...
JUST AHEAD OF THE FRONT. HAZE FROM THE BIG ISLAND COULD SPREAD TO
THE SMALLER ISLANDS LATE THURSDAY NIGHT INTO FRIDAY UNDER THE LIGHT
SOUTHERLY WIND FLOW. LAND BREEZES WILL RETURN TO THE ISLANDS AND MAY
ONCE AGAIN BRING CLEARING SKIES.

LATEST MODEL SOLUTIONS STILL HAVE THE FRONT ADVANCING TO NEAR KAUAI
BY FRIDAY NIGHT...OAHU EARLY SATURDAY...MAUI COUNTY AND THE BIG
ISLAND SATURDAY AND SATURDAY NIGHT. MAIN DYNAMICS ASSOCIATED WITH
THIS SYSTEM WILL STAY NORTH OF THE STATE...THOUGH LOW CLOUDS
ASSOCIATED WITH THIS FRONT WILL REACH THE ISLANDS...BRINGING SOME
SHOWERS. WINDS WILL TURN NORTHERLY BRIEFLY AS THE FRONT
PASSES...THUS CARRYING MUCH OF THE MOISTURE TO THE WINDWARD SLOPES
AND COASTS.

A SURFACE HIGH PRESSURE FROM THE FAR NORTHWEST WILL ADVANCE
SOUTHEAST OVER THE WEEKEND INTO NEXT WEEK. THIS HIGH WILL EVENTUALLY
SETTLE NORTHWEST OF THE STATE NEXT WEEK...BRINGING LIGHT TO MODERATE
NORTHEAST TRADE WINDS TO THE ISLANDS. MORE TYPICAL TRADE WIND
WEATHER WILL RETURN TO THE STATE.

&&

.AVIATION...
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT THE TERMINALS...WITH THE
EXCEPTION OF PHTO WHERE BRIEF PERIODS OF MVFR MAY OCCUR DUE TO LOWER
CEILINGS. NO AIRMET CONDITIONS ARE ANTICIPATED THROUGH EARLY
THURSDAY.

LOW-LEVEL WINDS WILL CONTINUE TO GRADUALLY EASE AS THE WEAK SURFACE
RIDGE NORTH OF THE ISLANDS SHIFTS SLOWLY SOUTHWARD TO A POSITION
JUST NORTH OF KAUAI THURSDAY MORNING. DUE TO THESE LIGHTER
BACKGROUND WINDS...EXPECT LOCAL LAND BREEZE CIRCULATIONS TO DEVELOP
OVER MOST ISLANDS BY EARLY THURSDAY MORNING. THESE DOWNSLOPING WINDS
WILL ALSO LIKELY CLEAR SKIES OVER MOST OF THE SMALLER ISLANDS...AND
THE LEEWARD BIG ISLAND.

LOCAL SEA BREEZE CIRCULATION ARE FORECAST TO DEVELOP ACROSS MOST
AREAS BY LATE THURSDAY MORNING. THESE SEA BREEZES WILL LIKELY RESULT
IN AFTERNOON CLOUDS AND ISOLATED SHOWERS...ESPECIALLY OVER LEEWARD
AND INTERIOR SECTIONS OF MOST ISLANDS.

&&

.MARINE...
WINDS AND SEAS ARE CURRENTLY BELOW SMALL CRAFT ADVISORY /SCA/
THRESHOLDS...AND ARE EXPECTED TO REMAIN BELOW CRITERIA FOR ALL
WATERS INTO NEXT WEEK. THEREFORE NO MARINE ADVISORY IS EXPECTED.
AN EXTENDED RUN OF SOUTH SWELL WILL BRING ELEVATED SURF ALONG SOUTH
FACING SHORES STARTING IN A DAY OR SO...WITH SURF HEIGHTS LIKELY
BELOW ADVISORY LEVELS THROUGH THE REST OF THE WEEK INTO NEXT.
HOWEVER...A PEAK OF SOUTH SWELL ON SUNDAY AND MONDAY COULD BRING
ADVISORY LEVEL SURF TO EXPOSED SOUTH FACING SHORES. A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND
EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...HUI
AVIATION...HOUSTON






000
FXHW60 PHFO 210646
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST WED MAY 20 2015

.SYNOPSIS...
WINDS WILL BECOME LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT
APPROACHES THE ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON
FRIDAY...THEN DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH
SUNDAY. THE FRONT WILL BRING A FEW SHOWERS...MAINLY TO WINDWARD AND
NORTH FACING SLOPES AND COASTS...AND A BRIEF SURGE OF NORTHEASTERLY
TRADE WINDS. LIGHT TO MODERATE NORTHEAST TRADE WINDS WILL THEN
PREVAIL INTO THE MIDDLE OF NEXT WEEK...DELIVERING BRIEF WINDWARD
SHOWERS MAINLY NIGHTS AND MORNINGS.

&&

.DISCUSSION...
TRADE WINDS CONTINUE TO DIMINISH THIS EVENING...AS A COLD FRONT FAR
NORTHWEST OF THE ISLANDS ADVANCES SOUTHEAST. THE FRONT IS DISPLACING
THE TRADE-WIND GENERATING SURFACE HIGH FAR NORTHEAST OF THE STATE
FURTHER AWAY FROM THE AREA. AS THE WINDS WEAKEN...LOW CLOUDS IN THE
ISLAND VICINITY WILL LINGER. LAND BREEZES WILL SLOWLY DEVELOP UNDER
NIGHT TIME COOLING...AND SHOULD LEAD TO CLEARING SKIES OVER THE
ISLANDS OVERNIGHT.

A WEAK SURFACE RIDGE EXTENDING SOUTHWEST FROM THE AFOREMENTIONED
SURFACE HIGH WILL BE PUSHED OVER THE ISLANDS ON THURSDAY...AHEAD OF
THE APPROACHING COLD FRONT. WINDS WILL REMAIN LIGHT AND
VARIABLE...ALLOWING ISLAND-SCALE LAND AND SEA BREEZES TO DOMINATE
THE ISLAND WEATHER. HENCE MOSTLY CLEAR SKIES ARE EXPECTED OVER THE
ISLANDS THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING
OVER INTERIOR AND MAUKA AREAS IN THE AFTERNOON. FORECAST SOLUTIONS
INDICATE A STABLE AIR MASS WILL PERSIST IN THE ISLAND
VICINITY...THEREFORE SHOWERS WILL BE LIMITED.

THE RIDGE WILL SHIFT FURTHER SOUTHEAST OF THE ISLANDS BY THURSDAY
NIGHT...WHILE WINDS WILL REMAIN LIGHT SOUTHERLY OVER THE STATE...
JUST AHEAD OF THE FRONT. HAZE FROM THE BIG ISLAND COULD SPREAD TO
THE SMALLER ISLANDS LATE THURSDAY NIGHT INTO FRIDAY UNDER THE LIGHT
SOUTHERLY WIND FLOW. LAND BREEZES WILL RETURN TO THE ISLANDS AND MAY
ONCE AGAIN BRING CLEARING SKIES.

LATEST MODEL SOLUTIONS STILL HAVE THE FRONT ADVANCING TO NEAR KAUAI
BY FRIDAY NIGHT...OAHU EARLY SATURDAY...MAUI COUNTY AND THE BIG
ISLAND SATURDAY AND SATURDAY NIGHT. MAIN DYNAMICS ASSOCIATED WITH
THIS SYSTEM WILL STAY NORTH OF THE STATE...THOUGH LOW CLOUDS
ASSOCIATED WITH THIS FRONT WILL REACH THE ISLANDS...BRINGING SOME
SHOWERS. WINDS WILL TURN NORTHERLY BRIEFLY AS THE FRONT
PASSES...THUS CARRYING MUCH OF THE MOISTURE TO THE WINDWARD SLOPES
AND COASTS.

A SURFACE HIGH PRESSURE FROM THE FAR NORTHWEST WILL ADVANCE
SOUTHEAST OVER THE WEEKEND INTO NEXT WEEK. THIS HIGH WILL EVENTUALLY
SETTLE NORTHWEST OF THE STATE NEXT WEEK...BRINGING LIGHT TO MODERATE
NORTHEAST TRADE WINDS TO THE ISLANDS. MORE TYPICAL TRADE WIND
WEATHER WILL RETURN TO THE STATE.

&&

.AVIATION...
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT THE TERMINALS...WITH THE
EXCEPTION OF PHTO WHERE BRIEF PERIODS OF MVFR MAY OCCUR DUE TO LOWER
CEILINGS. NO AIRMET CONDITIONS ARE ANTICIPATED THROUGH EARLY
THURSDAY.

LOW-LEVEL WINDS WILL CONTINUE TO GRADUALLY EASE AS THE WEAK SURFACE
RIDGE NORTH OF THE ISLANDS SHIFTS SLOWLY SOUTHWARD TO A POSITION
JUST NORTH OF KAUAI THURSDAY MORNING. DUE TO THESE LIGHTER
BACKGROUND WINDS...EXPECT LOCAL LAND BREEZE CIRCULATIONS TO DEVELOP
OVER MOST ISLANDS BY EARLY THURSDAY MORNING. THESE DOWNSLOPING WINDS
WILL ALSO LIKELY CLEAR SKIES OVER MOST OF THE SMALLER ISLANDS...AND
THE LEEWARD BIG ISLAND.

LOCAL SEA BREEZE CIRCULATION ARE FORECAST TO DEVELOP ACROSS MOST
AREAS BY LATE THURSDAY MORNING. THESE SEA BREEZES WILL LIKELY RESULT
IN AFTERNOON CLOUDS AND ISOLATED SHOWERS...ESPECIALLY OVER LEEWARD
AND INTERIOR SECTIONS OF MOST ISLANDS.

&&

.MARINE...
WINDS AND SEAS ARE CURRENTLY BELOW SMALL CRAFT ADVISORY /SCA/
THRESHOLDS...AND ARE EXPECTED TO REMAIN BELOW CRITERIA FOR ALL
WATERS INTO NEXT WEEK. THEREFORE NO MARINE ADVISORY IS EXPECTED.
AN EXTENDED RUN OF SOUTH SWELL WILL BRING ELEVATED SURF ALONG SOUTH
FACING SHORES STARTING IN A DAY OR SO...WITH SURF HEIGHTS LIKELY
BELOW ADVISORY LEVELS THROUGH THE REST OF THE WEEK INTO NEXT.
HOWEVER...A PEAK OF SOUTH SWELL ON SUNDAY AND MONDAY COULD BRING
ADVISORY LEVEL SURF TO EXPOSED SOUTH FACING SHORES. A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND
EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...HUI
AVIATION...HOUSTON







000
FXHW60 PHFO 210646
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST WED MAY 20 2015

.SYNOPSIS...
WINDS WILL BECOME LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT
APPROACHES THE ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON
FRIDAY...THEN DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH
SUNDAY. THE FRONT WILL BRING A FEW SHOWERS...MAINLY TO WINDWARD AND
NORTH FACING SLOPES AND COASTS...AND A BRIEF SURGE OF NORTHEASTERLY
TRADE WINDS. LIGHT TO MODERATE NORTHEAST TRADE WINDS WILL THEN
PREVAIL INTO THE MIDDLE OF NEXT WEEK...DELIVERING BRIEF WINDWARD
SHOWERS MAINLY NIGHTS AND MORNINGS.

&&

.DISCUSSION...
TRADE WINDS CONTINUE TO DIMINISH THIS EVENING...AS A COLD FRONT FAR
NORTHWEST OF THE ISLANDS ADVANCES SOUTHEAST. THE FRONT IS DISPLACING
THE TRADE-WIND GENERATING SURFACE HIGH FAR NORTHEAST OF THE STATE
FURTHER AWAY FROM THE AREA. AS THE WINDS WEAKEN...LOW CLOUDS IN THE
ISLAND VICINITY WILL LINGER. LAND BREEZES WILL SLOWLY DEVELOP UNDER
NIGHT TIME COOLING...AND SHOULD LEAD TO CLEARING SKIES OVER THE
ISLANDS OVERNIGHT.

A WEAK SURFACE RIDGE EXTENDING SOUTHWEST FROM THE AFOREMENTIONED
SURFACE HIGH WILL BE PUSHED OVER THE ISLANDS ON THURSDAY...AHEAD OF
THE APPROACHING COLD FRONT. WINDS WILL REMAIN LIGHT AND
VARIABLE...ALLOWING ISLAND-SCALE LAND AND SEA BREEZES TO DOMINATE
THE ISLAND WEATHER. HENCE MOSTLY CLEAR SKIES ARE EXPECTED OVER THE
ISLANDS THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING
OVER INTERIOR AND MAUKA AREAS IN THE AFTERNOON. FORECAST SOLUTIONS
INDICATE A STABLE AIR MASS WILL PERSIST IN THE ISLAND
VICINITY...THEREFORE SHOWERS WILL BE LIMITED.

THE RIDGE WILL SHIFT FURTHER SOUTHEAST OF THE ISLANDS BY THURSDAY
NIGHT...WHILE WINDS WILL REMAIN LIGHT SOUTHERLY OVER THE STATE...
JUST AHEAD OF THE FRONT. HAZE FROM THE BIG ISLAND COULD SPREAD TO
THE SMALLER ISLANDS LATE THURSDAY NIGHT INTO FRIDAY UNDER THE LIGHT
SOUTHERLY WIND FLOW. LAND BREEZES WILL RETURN TO THE ISLANDS AND MAY
ONCE AGAIN BRING CLEARING SKIES.

LATEST MODEL SOLUTIONS STILL HAVE THE FRONT ADVANCING TO NEAR KAUAI
BY FRIDAY NIGHT...OAHU EARLY SATURDAY...MAUI COUNTY AND THE BIG
ISLAND SATURDAY AND SATURDAY NIGHT. MAIN DYNAMICS ASSOCIATED WITH
THIS SYSTEM WILL STAY NORTH OF THE STATE...THOUGH LOW CLOUDS
ASSOCIATED WITH THIS FRONT WILL REACH THE ISLANDS...BRINGING SOME
SHOWERS. WINDS WILL TURN NORTHERLY BRIEFLY AS THE FRONT
PASSES...THUS CARRYING MUCH OF THE MOISTURE TO THE WINDWARD SLOPES
AND COASTS.

A SURFACE HIGH PRESSURE FROM THE FAR NORTHWEST WILL ADVANCE
SOUTHEAST OVER THE WEEKEND INTO NEXT WEEK. THIS HIGH WILL EVENTUALLY
SETTLE NORTHWEST OF THE STATE NEXT WEEK...BRINGING LIGHT TO MODERATE
NORTHEAST TRADE WINDS TO THE ISLANDS. MORE TYPICAL TRADE WIND
WEATHER WILL RETURN TO THE STATE.

&&

.AVIATION...
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT THE TERMINALS...WITH THE
EXCEPTION OF PHTO WHERE BRIEF PERIODS OF MVFR MAY OCCUR DUE TO LOWER
CEILINGS. NO AIRMET CONDITIONS ARE ANTICIPATED THROUGH EARLY
THURSDAY.

LOW-LEVEL WINDS WILL CONTINUE TO GRADUALLY EASE AS THE WEAK SURFACE
RIDGE NORTH OF THE ISLANDS SHIFTS SLOWLY SOUTHWARD TO A POSITION
JUST NORTH OF KAUAI THURSDAY MORNING. DUE TO THESE LIGHTER
BACKGROUND WINDS...EXPECT LOCAL LAND BREEZE CIRCULATIONS TO DEVELOP
OVER MOST ISLANDS BY EARLY THURSDAY MORNING. THESE DOWNSLOPING WINDS
WILL ALSO LIKELY CLEAR SKIES OVER MOST OF THE SMALLER ISLANDS...AND
THE LEEWARD BIG ISLAND.

LOCAL SEA BREEZE CIRCULATION ARE FORECAST TO DEVELOP ACROSS MOST
AREAS BY LATE THURSDAY MORNING. THESE SEA BREEZES WILL LIKELY RESULT
IN AFTERNOON CLOUDS AND ISOLATED SHOWERS...ESPECIALLY OVER LEEWARD
AND INTERIOR SECTIONS OF MOST ISLANDS.

&&

.MARINE...
WINDS AND SEAS ARE CURRENTLY BELOW SMALL CRAFT ADVISORY /SCA/
THRESHOLDS...AND ARE EXPECTED TO REMAIN BELOW CRITERIA FOR ALL
WATERS INTO NEXT WEEK. THEREFORE NO MARINE ADVISORY IS EXPECTED.
AN EXTENDED RUN OF SOUTH SWELL WILL BRING ELEVATED SURF ALONG SOUTH
FACING SHORES STARTING IN A DAY OR SO...WITH SURF HEIGHTS LIKELY
BELOW ADVISORY LEVELS THROUGH THE REST OF THE WEEK INTO NEXT.
HOWEVER...A PEAK OF SOUTH SWELL ON SUNDAY AND MONDAY COULD BRING
ADVISORY LEVEL SURF TO EXPOSED SOUTH FACING SHORES. A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND
EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...HUI
AVIATION...HOUSTON







000
FXHW60 PHFO 210646
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST WED MAY 20 2015

.SYNOPSIS...
WINDS WILL BECOME LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT
APPROACHES THE ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON
FRIDAY...THEN DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH
SUNDAY. THE FRONT WILL BRING A FEW SHOWERS...MAINLY TO WINDWARD AND
NORTH FACING SLOPES AND COASTS...AND A BRIEF SURGE OF NORTHEASTERLY
TRADE WINDS. LIGHT TO MODERATE NORTHEAST TRADE WINDS WILL THEN
PREVAIL INTO THE MIDDLE OF NEXT WEEK...DELIVERING BRIEF WINDWARD
SHOWERS MAINLY NIGHTS AND MORNINGS.

&&

.DISCUSSION...
TRADE WINDS CONTINUE TO DIMINISH THIS EVENING...AS A COLD FRONT FAR
NORTHWEST OF THE ISLANDS ADVANCES SOUTHEAST. THE FRONT IS DISPLACING
THE TRADE-WIND GENERATING SURFACE HIGH FAR NORTHEAST OF THE STATE
FURTHER AWAY FROM THE AREA. AS THE WINDS WEAKEN...LOW CLOUDS IN THE
ISLAND VICINITY WILL LINGER. LAND BREEZES WILL SLOWLY DEVELOP UNDER
NIGHT TIME COOLING...AND SHOULD LEAD TO CLEARING SKIES OVER THE
ISLANDS OVERNIGHT.

A WEAK SURFACE RIDGE EXTENDING SOUTHWEST FROM THE AFOREMENTIONED
SURFACE HIGH WILL BE PUSHED OVER THE ISLANDS ON THURSDAY...AHEAD OF
THE APPROACHING COLD FRONT. WINDS WILL REMAIN LIGHT AND
VARIABLE...ALLOWING ISLAND-SCALE LAND AND SEA BREEZES TO DOMINATE
THE ISLAND WEATHER. HENCE MOSTLY CLEAR SKIES ARE EXPECTED OVER THE
ISLANDS THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING
OVER INTERIOR AND MAUKA AREAS IN THE AFTERNOON. FORECAST SOLUTIONS
INDICATE A STABLE AIR MASS WILL PERSIST IN THE ISLAND
VICINITY...THEREFORE SHOWERS WILL BE LIMITED.

THE RIDGE WILL SHIFT FURTHER SOUTHEAST OF THE ISLANDS BY THURSDAY
NIGHT...WHILE WINDS WILL REMAIN LIGHT SOUTHERLY OVER THE STATE...
JUST AHEAD OF THE FRONT. HAZE FROM THE BIG ISLAND COULD SPREAD TO
THE SMALLER ISLANDS LATE THURSDAY NIGHT INTO FRIDAY UNDER THE LIGHT
SOUTHERLY WIND FLOW. LAND BREEZES WILL RETURN TO THE ISLANDS AND MAY
ONCE AGAIN BRING CLEARING SKIES.

LATEST MODEL SOLUTIONS STILL HAVE THE FRONT ADVANCING TO NEAR KAUAI
BY FRIDAY NIGHT...OAHU EARLY SATURDAY...MAUI COUNTY AND THE BIG
ISLAND SATURDAY AND SATURDAY NIGHT. MAIN DYNAMICS ASSOCIATED WITH
THIS SYSTEM WILL STAY NORTH OF THE STATE...THOUGH LOW CLOUDS
ASSOCIATED WITH THIS FRONT WILL REACH THE ISLANDS...BRINGING SOME
SHOWERS. WINDS WILL TURN NORTHERLY BRIEFLY AS THE FRONT
PASSES...THUS CARRYING MUCH OF THE MOISTURE TO THE WINDWARD SLOPES
AND COASTS.

A SURFACE HIGH PRESSURE FROM THE FAR NORTHWEST WILL ADVANCE
SOUTHEAST OVER THE WEEKEND INTO NEXT WEEK. THIS HIGH WILL EVENTUALLY
SETTLE NORTHWEST OF THE STATE NEXT WEEK...BRINGING LIGHT TO MODERATE
NORTHEAST TRADE WINDS TO THE ISLANDS. MORE TYPICAL TRADE WIND
WEATHER WILL RETURN TO THE STATE.

&&

.AVIATION...
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT THE TERMINALS...WITH THE
EXCEPTION OF PHTO WHERE BRIEF PERIODS OF MVFR MAY OCCUR DUE TO LOWER
CEILINGS. NO AIRMET CONDITIONS ARE ANTICIPATED THROUGH EARLY
THURSDAY.

LOW-LEVEL WINDS WILL CONTINUE TO GRADUALLY EASE AS THE WEAK SURFACE
RIDGE NORTH OF THE ISLANDS SHIFTS SLOWLY SOUTHWARD TO A POSITION
JUST NORTH OF KAUAI THURSDAY MORNING. DUE TO THESE LIGHTER
BACKGROUND WINDS...EXPECT LOCAL LAND BREEZE CIRCULATIONS TO DEVELOP
OVER MOST ISLANDS BY EARLY THURSDAY MORNING. THESE DOWNSLOPING WINDS
WILL ALSO LIKELY CLEAR SKIES OVER MOST OF THE SMALLER ISLANDS...AND
THE LEEWARD BIG ISLAND.

LOCAL SEA BREEZE CIRCULATION ARE FORECAST TO DEVELOP ACROSS MOST
AREAS BY LATE THURSDAY MORNING. THESE SEA BREEZES WILL LIKELY RESULT
IN AFTERNOON CLOUDS AND ISOLATED SHOWERS...ESPECIALLY OVER LEEWARD
AND INTERIOR SECTIONS OF MOST ISLANDS.

&&

.MARINE...
WINDS AND SEAS ARE CURRENTLY BELOW SMALL CRAFT ADVISORY /SCA/
THRESHOLDS...AND ARE EXPECTED TO REMAIN BELOW CRITERIA FOR ALL
WATERS INTO NEXT WEEK. THEREFORE NO MARINE ADVISORY IS EXPECTED.
AN EXTENDED RUN OF SOUTH SWELL WILL BRING ELEVATED SURF ALONG SOUTH
FACING SHORES STARTING IN A DAY OR SO...WITH SURF HEIGHTS LIKELY
BELOW ADVISORY LEVELS THROUGH THE REST OF THE WEEK INTO NEXT.
HOWEVER...A PEAK OF SOUTH SWELL ON SUNDAY AND MONDAY COULD BRING
ADVISORY LEVEL SURF TO EXPOSED SOUTH FACING SHORES. A COUPLE OF
SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND
EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW ADVISORY LEVELS.

&&

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

&&

$$

DISCUSSION/MARINE...HUI
AVIATION...HOUSTON






000
FXHW60 PHFO 210206 CCA
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST WED MAY 20 2015

.SYNOPSIS...
TRADE WINDS WILL DIMINISH OVERNIGHT AND BECOME LIGHT AND VARIABLE ON
THURSDAY...AS A WEAK FRONT APPROACHES THE ISLANDS. THE FRONT IS
EXPECTED TO REACH KAUAI ON FRIDAY...THEN DISSIPATE AS IT MOVES DOWN
THE ISLAND CHAIN THROUGH SUNDAY. THE FRONT WILL BRING A FEW
SHOWERS...MAINLY TO WINDWARD AND NORTH FACING SLOPES AND COASTS...
AND A BRIEF SURGE OF NORTHEASTERLY TRADE WINDS. LIGHT TO MODERATE
NORTHEAST TRADE WINDS WILL THEN PREVAIL INTO THE MIDDLE OF NEXT
WEEK...DELIVERING BRIEF WINDWARD SHOWERS THAT WILL FAVOR NIGHTS AND
MORNINGS.

&&

.DISCUSSION...
CURRENTLY...DIMINISHING...YET LOCALLY MODERATE...TRADE WINDS ARE
BEING SUPPORTED BY A GRADUALLY WEAKENING 1025 MB HIGH CENTERED ABOUT
800 MILES NE OF THE ISLANDS. THE ISLAND ATMOSPHERE REMAINS STABLE
WITH A SUBSIDENCE INVERSION BASED AROUND 8 KFT...BUT A PESKY AREA OF
STABLE AND SHOWERY LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW
CONTINUES TO PEPPER ISLAND SKIES...MAINLY OVER KAUAI AND OAHU. THE
TRADE WINDS ARE DIMINISHING DUE TO A SE-WARD MOVING FRONT THAT IS
CURRENTLY ABOUT 700 MILES NW OF KAUAI. THE FRONT IS FORCING THE HIGH
E-WARD WHILE ALSO ERODING THE WESTERN PORTION OF IT/S ASSOCIATED
RIDGE. ISLAND SURFACE PRESSURES ARE DOWN ABOUT 2 MB OVER THE PAST 24
HOURS IN RESPONSE. OVERNIGHT...THE EXPECTATION IS THAT CLOUDS WILL
GRADUALLY DIMINISH THROUGH THE EVENING HOURS...ESPECIALLY OVER
LEEWARD AREAS...AS THE TRADE WINDS GIVE WAY TO LAND BREEZES BY
MORNING. THE LINGERING TRADE WINDS MAY DELIVER A SHOWER OR TWO TO
WINDWARD AREAS THROUGH THE NIGHT HOWEVER.

A WEAK RIDGE EXTENDING SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER
THE ISLANDS ON THURSDAY...AHEAD OF THE APPROACHING COLD FRONT. THIS
WILL LEAD TO LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-
SCALE LAND AND SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY
CLEAR SKIES ARE EXPECTED OVER THE ISLANDS THURSDAY MORNING...WITH
CLOUDS AND A FEW SHOWERS DEVELOPING OVER INTERIOR AND MAUKA AREAS IN
THE AFTERNOON. ATMOSPHERIC STABILITY WILL REMAIN HIGH AND THUS HEAVY
SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
THE LIGHT WINDS FAVORING A SOUTHERLY DIRECTION COULD BRING SOME HAZE
FROM THE BIG ISLAND OVER THE SMALLER ISLANDS THURSDAY NIGHT AND
FRIDAY. WITH RESPECT TO THE FRONT...LATEST GUIDANCE SHOWS A WEAK LOW
DEVELOPING BETWEEN 28N AND 30N THURSDAY AND FRIDAY...WHICH IS NOW
EXPECTED TO PROVIDE SUFFICIENT PUSH TO SHUNT THE FRONT DOWN THE
ISLAND CHAIN...ALTHOUGH THE WEAKENING BOUNDARY IS NOT EXPECTED TO
PRODUCE WIDESPREAD RAINFALL. THE FRONT IS EXPECTED OVER KAUAI BY
FRIDAY NIGHT...OAHU EARLY SATURDAY...MAUI COUNTY AND THE BIG ISLAND
SATURDAY AND SATURDAY NIGHT...AND THEN CLEARING THE BIG ISLAND ON
SUNDAY. WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE
FRONT PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD
SLOPES AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM LATE THIS WEEKEND INTO NEXT WEEK...AND THUS
LIGHT TO MODERATE NE TRADE WINDS ARE EXPECTED TO BRING BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
VFR WILL PREVAIL AT ALL TERMINALS OVERNIGHT. WINDS WILL BEGIN TO
EASE AS THE RIDGE PUSHES SOUTH TO JUST NORTH OF KAUAI THURSDAY
MORNING. LOCALIZED LAND BREEZES ARE EXPECTED TO TAKE HOLD BY EARLY
THURSDAY MORNING. INTERIOR CLOUDS...ESPECIALLY OVER OAHU AND
LEEWARD BIG ISLAND WILL BEGIN TO CLEAR WITH SUNSET. TOMORROW...
EXPECT WIDESPREAD SEA BREEZES AND AFTERNOON INTERIOR CLOUDS AND
SHOWERS. NO AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
NO MARINE ADVISORIES OR WARNINGS ARE CURRENTLY POSTED. WINDS AND
SEAS ARE CURRENTLY BELOW SMALL CRAFT ADVISORY /SCA/ THRESHOLDS...AND
ARE EXPECTED TO REMAIN BELOW CRITERIA FOR ALL WATERS INTO NEXT WEEK.
A COUPLE OF SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE
WEEKEND AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW
ADVISORY LEVELS. AN EXTENDED RUN OF SURF ALONG S FACING SHORES IS
POISED TO BEGIN OVER THE NEXT 24 HOURS OR SO...WITH SEVERAL MODERATE
S TO SSW SWELLS EXPECTED TO PRODUCE SURF NEAR BUT LIKELY BELOW
ADVISORY LEVELS FOR MOST OF THE NEXT WEEK. HOWEVER...A PEAK ON
SUNDAY AND MONDAY COULD BRING ADVISORY LEVEL SURF TO EXPOSED S
FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON








000
FXHW60 PHFO 210206 CCA
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST WED MAY 20 2015

.SYNOPSIS...
TRADE WINDS WILL DIMINISH OVERNIGHT AND BECOME LIGHT AND VARIABLE ON
THURSDAY...AS A WEAK FRONT APPROACHES THE ISLANDS. THE FRONT IS
EXPECTED TO REACH KAUAI ON FRIDAY...THEN DISSIPATE AS IT MOVES DOWN
THE ISLAND CHAIN THROUGH SUNDAY. THE FRONT WILL BRING A FEW
SHOWERS...MAINLY TO WINDWARD AND NORTH FACING SLOPES AND COASTS...
AND A BRIEF SURGE OF NORTHEASTERLY TRADE WINDS. LIGHT TO MODERATE
NORTHEAST TRADE WINDS WILL THEN PREVAIL INTO THE MIDDLE OF NEXT
WEEK...DELIVERING BRIEF WINDWARD SHOWERS THAT WILL FAVOR NIGHTS AND
MORNINGS.

&&

.DISCUSSION...
CURRENTLY...DIMINISHING...YET LOCALLY MODERATE...TRADE WINDS ARE
BEING SUPPORTED BY A GRADUALLY WEAKENING 1025 MB HIGH CENTERED ABOUT
800 MILES NE OF THE ISLANDS. THE ISLAND ATMOSPHERE REMAINS STABLE
WITH A SUBSIDENCE INVERSION BASED AROUND 8 KFT...BUT A PESKY AREA OF
STABLE AND SHOWERY LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW
CONTINUES TO PEPPER ISLAND SKIES...MAINLY OVER KAUAI AND OAHU. THE
TRADE WINDS ARE DIMINISHING DUE TO A SE-WARD MOVING FRONT THAT IS
CURRENTLY ABOUT 700 MILES NW OF KAUAI. THE FRONT IS FORCING THE HIGH
E-WARD WHILE ALSO ERODING THE WESTERN PORTION OF IT/S ASSOCIATED
RIDGE. ISLAND SURFACE PRESSURES ARE DOWN ABOUT 2 MB OVER THE PAST 24
HOURS IN RESPONSE. OVERNIGHT...THE EXPECTATION IS THAT CLOUDS WILL
GRADUALLY DIMINISH THROUGH THE EVENING HOURS...ESPECIALLY OVER
LEEWARD AREAS...AS THE TRADE WINDS GIVE WAY TO LAND BREEZES BY
MORNING. THE LINGERING TRADE WINDS MAY DELIVER A SHOWER OR TWO TO
WINDWARD AREAS THROUGH THE NIGHT HOWEVER.

A WEAK RIDGE EXTENDING SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER
THE ISLANDS ON THURSDAY...AHEAD OF THE APPROACHING COLD FRONT. THIS
WILL LEAD TO LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-
SCALE LAND AND SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY
CLEAR SKIES ARE EXPECTED OVER THE ISLANDS THURSDAY MORNING...WITH
CLOUDS AND A FEW SHOWERS DEVELOPING OVER INTERIOR AND MAUKA AREAS IN
THE AFTERNOON. ATMOSPHERIC STABILITY WILL REMAIN HIGH AND THUS HEAVY
SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
THE LIGHT WINDS FAVORING A SOUTHERLY DIRECTION COULD BRING SOME HAZE
FROM THE BIG ISLAND OVER THE SMALLER ISLANDS THURSDAY NIGHT AND
FRIDAY. WITH RESPECT TO THE FRONT...LATEST GUIDANCE SHOWS A WEAK LOW
DEVELOPING BETWEEN 28N AND 30N THURSDAY AND FRIDAY...WHICH IS NOW
EXPECTED TO PROVIDE SUFFICIENT PUSH TO SHUNT THE FRONT DOWN THE
ISLAND CHAIN...ALTHOUGH THE WEAKENING BOUNDARY IS NOT EXPECTED TO
PRODUCE WIDESPREAD RAINFALL. THE FRONT IS EXPECTED OVER KAUAI BY
FRIDAY NIGHT...OAHU EARLY SATURDAY...MAUI COUNTY AND THE BIG ISLAND
SATURDAY AND SATURDAY NIGHT...AND THEN CLEARING THE BIG ISLAND ON
SUNDAY. WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE
FRONT PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD
SLOPES AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM LATE THIS WEEKEND INTO NEXT WEEK...AND THUS
LIGHT TO MODERATE NE TRADE WINDS ARE EXPECTED TO BRING BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
VFR WILL PREVAIL AT ALL TERMINALS OVERNIGHT. WINDS WILL BEGIN TO
EASE AS THE RIDGE PUSHES SOUTH TO JUST NORTH OF KAUAI THURSDAY
MORNING. LOCALIZED LAND BREEZES ARE EXPECTED TO TAKE HOLD BY EARLY
THURSDAY MORNING. INTERIOR CLOUDS...ESPECIALLY OVER OAHU AND
LEEWARD BIG ISLAND WILL BEGIN TO CLEAR WITH SUNSET. TOMORROW...
EXPECT WIDESPREAD SEA BREEZES AND AFTERNOON INTERIOR CLOUDS AND
SHOWERS. NO AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
NO MARINE ADVISORIES OR WARNINGS ARE CURRENTLY POSTED. WINDS AND
SEAS ARE CURRENTLY BELOW SMALL CRAFT ADVISORY /SCA/ THRESHOLDS...AND
ARE EXPECTED TO REMAIN BELOW CRITERIA FOR ALL WATERS INTO NEXT WEEK.
A COUPLE OF SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE
WEEKEND AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW
ADVISORY LEVELS. AN EXTENDED RUN OF SURF ALONG S FACING SHORES IS
POISED TO BEGIN OVER THE NEXT 24 HOURS OR SO...WITH SEVERAL MODERATE
S TO SSW SWELLS EXPECTED TO PRODUCE SURF NEAR BUT LIKELY BELOW
ADVISORY LEVELS FOR MOST OF THE NEXT WEEK. HOWEVER...A PEAK ON
SUNDAY AND MONDAY COULD BRING ADVISORY LEVEL SURF TO EXPOSED S
FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 210204
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST WED MAY 20 2015

.SYNOPSIS...
TRADE WINDS WILL DIMINISH OVERNIGHT AND BECOME LIGHT AND VARIABLE ON
THURSDAY...AS A WEAK FRONT APPROACHES THE ISLANDS. THE FRONT IS
EXPECTED TO REACH KAUAI ON FRIDAY...THEN DISSIPATE AS IT MOVES DOWN
THE ISLAND CHAIN THROUGH SATURDAY. THE FRONT WILL BRING A FEW
SHOWERS...MAINLY TO WINDWARD AND NORTH FACING SLOPES AND
COASTS...AND A BRIEF SURGE OF NORTHEASTERLY TRADE WINDS. LIGHT TO
MODERATE NORTHEAST TRADE WINDS WILL THEN PREVAIL INTO THE MIDDLE OF
NEXT WEEK...DELIVERING BRIEF WINDWARD SHOWERS THAT WILL FAVOR
NIGHTS AND MORNINGS.

&&

.DISCUSSION...
CURRENTLY...DIMINISHING...YET LOCALLY MODERATE...TRADE WINDS ARE
BEING SUPPORTED BY A GRADUALLY WEAKENING 1025 MB HIGH CENTERED ABOUT
800 MILES NE OF THE ISLANDS. THE ISLAND ATMOSPHERE REMAINS STABLE
WITH A SUBSIDENCE INVERSION BASED AROUND 8 KFT...BUT A PESKY AREA OF
STABLE AND SHOWERY LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW
CONTINUES TO PEPPER ISLAND SKIES...MAINLY OVER KAUAI AND OAHU. THE
TRADE WINDS ARE DIMINISHING DUE TO A SE-WARD MOVING FRONT THAT IS
CURRENTLY ABOUT 700 MILES NW OF KAUAI. THE FRONT IS FORCING THE HIGH
E-WARD WHILE ALSO ERODING THE WESTERN PORTION OF IT/S ASSOCIATED
RIDGE. ISLAND SURFACE PRESSURES ARE DOWN ABOUT 2 MB OVER THE PAST 24
HOURS IN RESPONSE. OVERNIGHT...THE EXPECTATION IS THAT CLOUDS WILL
GRADUALLY DIMINISH THROUGH THE EVENING HOURS...ESPECIALLY OVER
LEEWARD AREAS...AS THE TRADE WINDS GIVE WAY TO LAND BREEZES BY
MORNING. THE LINGERING TRADE WINDS MAY DELIVER A SHOWER OR TWO TO
WINDWARD AREAS THROUGH THE NIGHT HOWEVER.

A WEAK RIDGE EXTENDING SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER
THE ISLANDS ON THURSDAY...AHEAD OF THE APPROACHING COLD FRONT. THIS
WILL LEAD TO LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-
SCALE LAND AND SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY
CLEAR SKIES ARE EXPECTED OVER THE ISLANDS THURSDAY MORNING...WITH
CLOUDS AND A FEW SHOWERS DEVELOPING OVER INTERIOR AND MAUKA AREAS IN
THE AFTERNOON. ATMOSPHERIC STABILITY WILL REMAIN HIGH AND THUS HEAVY
SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
THE LIGHT WINDS FAVORING A SOUTHERLY DIRECTION COULD BRING SOME HAZE
FROM THE BIG ISLAND OVER THE SMALLER ISLANDS THURSDAY NIGHT AND
FRIDAY. WITH RESPECT TO THE FRONT...LATEST GUIDANCE SHOWS A WEAK LOW
DEVELOPING BETWEEN 28N AND 30N THURSDAY AND FRIDAY...WHICH IS NOW
EXPECTED TO PROVIDE SUFFICIENT PUSH TO SHUNT THE FRONT DOWN THE
ISLAND CHAIN...ALTHOUGH THE WEAKENING BOUNDARY IS NOT EXPECTED TO
PRODUCE WIDESPREAD RAINFALL. THE FRONT IS EXPECTED OVER KAUAI BY
FRIDAY NIGHT...OAHU EARLY SATURDAY...MAUI COUNTY AND THE BIG ISLAND
SATURDAY AND SATURDAY NIGHT...AND THEN CLEARING THE BIG ISLAND ON
SUNDAY. WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE
FRONT PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD
SLOPES AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM LATE THIS WEEKEND INTO NEXT WEEK...AND THUS
LIGHT TO MODERATE NE TRADE WINDS ARE EXPECTED TO BRING BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
VFR WILL PREVAIL AT ALL TERMINALS OVERNIGHT. WINDS WILL BEGIN TO
EASE AS THE RIDGE PUSHES SOUTH TO JUST NORTH OF KAUAI THURSDAY
MORNING. LOCALIZED LAND BREEZES ARE EXPECTED TO TAKE HOLD BY EARLY
THURSDAY MORNING. INTERIOR CLOUDS...ESPECIALLY OVER OAHU AND
LEEWARD BIG ISLAND WILL BEGIN TO CLEAR WITH SUNSET. TOMORROW...
EXPECT WIDESPREAD SEA BREEZES AND AFTERNOON INTERIOR CLOUDS AND
SHOWERS. NO AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
NO MARINE ADVISORIES OR WARNINGS ARE CURRENTLY POSTED. WINDS AND
SEAS ARE CURRENTLY BELOW SMALL CRAFT ADVISORY /SCA/ THRESHOLDS...AND
ARE EXPECTED TO REMAIN BELOW CRITERIA FOR ALL WATERS INTO NEXT WEEK.
A COUPLE OF SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE
WEEKEND AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW
ADVISORY LEVELS. AN EXTENDED RUN OF SURF ALONG S FACING SHORES IS
POISED TO BEGIN OVER THE NEXT 24 HOURS OR SO...WITH SEVERAL MODERATE
S TO SSW SWELLS EXPECTED TO PRODUCE SURF NEAR BUT LIKELY BELOW
ADVISORY LEVELS FOR MOST OF THE NEXT WEEK. HOWEVER...A PEAK ON
SUNDAY AND MONDAY COULD BRING ADVISORY LEVEL SURF TO EXPOSED S
FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 210204
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST WED MAY 20 2015

.SYNOPSIS...
TRADE WINDS WILL DIMINISH OVERNIGHT AND BECOME LIGHT AND VARIABLE ON
THURSDAY...AS A WEAK FRONT APPROACHES THE ISLANDS. THE FRONT IS
EXPECTED TO REACH KAUAI ON FRIDAY...THEN DISSIPATE AS IT MOVES DOWN
THE ISLAND CHAIN THROUGH SATURDAY. THE FRONT WILL BRING A FEW
SHOWERS...MAINLY TO WINDWARD AND NORTH FACING SLOPES AND
COASTS...AND A BRIEF SURGE OF NORTHEASTERLY TRADE WINDS. LIGHT TO
MODERATE NORTHEAST TRADE WINDS WILL THEN PREVAIL INTO THE MIDDLE OF
NEXT WEEK...DELIVERING BRIEF WINDWARD SHOWERS THAT WILL FAVOR
NIGHTS AND MORNINGS.

&&

.DISCUSSION...
CURRENTLY...DIMINISHING...YET LOCALLY MODERATE...TRADE WINDS ARE
BEING SUPPORTED BY A GRADUALLY WEAKENING 1025 MB HIGH CENTERED ABOUT
800 MILES NE OF THE ISLANDS. THE ISLAND ATMOSPHERE REMAINS STABLE
WITH A SUBSIDENCE INVERSION BASED AROUND 8 KFT...BUT A PESKY AREA OF
STABLE AND SHOWERY LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW
CONTINUES TO PEPPER ISLAND SKIES...MAINLY OVER KAUAI AND OAHU. THE
TRADE WINDS ARE DIMINISHING DUE TO A SE-WARD MOVING FRONT THAT IS
CURRENTLY ABOUT 700 MILES NW OF KAUAI. THE FRONT IS FORCING THE HIGH
E-WARD WHILE ALSO ERODING THE WESTERN PORTION OF IT/S ASSOCIATED
RIDGE. ISLAND SURFACE PRESSURES ARE DOWN ABOUT 2 MB OVER THE PAST 24
HOURS IN RESPONSE. OVERNIGHT...THE EXPECTATION IS THAT CLOUDS WILL
GRADUALLY DIMINISH THROUGH THE EVENING HOURS...ESPECIALLY OVER
LEEWARD AREAS...AS THE TRADE WINDS GIVE WAY TO LAND BREEZES BY
MORNING. THE LINGERING TRADE WINDS MAY DELIVER A SHOWER OR TWO TO
WINDWARD AREAS THROUGH THE NIGHT HOWEVER.

A WEAK RIDGE EXTENDING SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER
THE ISLANDS ON THURSDAY...AHEAD OF THE APPROACHING COLD FRONT. THIS
WILL LEAD TO LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-
SCALE LAND AND SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY
CLEAR SKIES ARE EXPECTED OVER THE ISLANDS THURSDAY MORNING...WITH
CLOUDS AND A FEW SHOWERS DEVELOPING OVER INTERIOR AND MAUKA AREAS IN
THE AFTERNOON. ATMOSPHERIC STABILITY WILL REMAIN HIGH AND THUS HEAVY
SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
THE LIGHT WINDS FAVORING A SOUTHERLY DIRECTION COULD BRING SOME HAZE
FROM THE BIG ISLAND OVER THE SMALLER ISLANDS THURSDAY NIGHT AND
FRIDAY. WITH RESPECT TO THE FRONT...LATEST GUIDANCE SHOWS A WEAK LOW
DEVELOPING BETWEEN 28N AND 30N THURSDAY AND FRIDAY...WHICH IS NOW
EXPECTED TO PROVIDE SUFFICIENT PUSH TO SHUNT THE FRONT DOWN THE
ISLAND CHAIN...ALTHOUGH THE WEAKENING BOUNDARY IS NOT EXPECTED TO
PRODUCE WIDESPREAD RAINFALL. THE FRONT IS EXPECTED OVER KAUAI BY
FRIDAY NIGHT...OAHU EARLY SATURDAY...MAUI COUNTY AND THE BIG ISLAND
SATURDAY AND SATURDAY NIGHT...AND THEN CLEARING THE BIG ISLAND ON
SUNDAY. WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE
FRONT PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD
SLOPES AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM LATE THIS WEEKEND INTO NEXT WEEK...AND THUS
LIGHT TO MODERATE NE TRADE WINDS ARE EXPECTED TO BRING BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
VFR WILL PREVAIL AT ALL TERMINALS OVERNIGHT. WINDS WILL BEGIN TO
EASE AS THE RIDGE PUSHES SOUTH TO JUST NORTH OF KAUAI THURSDAY
MORNING. LOCALIZED LAND BREEZES ARE EXPECTED TO TAKE HOLD BY EARLY
THURSDAY MORNING. INTERIOR CLOUDS...ESPECIALLY OVER OAHU AND
LEEWARD BIG ISLAND WILL BEGIN TO CLEAR WITH SUNSET. TOMORROW...
EXPECT WIDESPREAD SEA BREEZES AND AFTERNOON INTERIOR CLOUDS AND
SHOWERS. NO AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
NO MARINE ADVISORIES OR WARNINGS ARE CURRENTLY POSTED. WINDS AND
SEAS ARE CURRENTLY BELOW SMALL CRAFT ADVISORY /SCA/ THRESHOLDS...AND
ARE EXPECTED TO REMAIN BELOW CRITERIA FOR ALL WATERS INTO NEXT WEEK.
A COUPLE OF SMALL SWELLS FROM THE NNW AND WNW ARE EXPECTED OVER THE
WEEKEND AND EARLY NEXT WEEK...WITH RESULTANT SURF WELL BELOW
ADVISORY LEVELS. AN EXTENDED RUN OF SURF ALONG S FACING SHORES IS
POISED TO BEGIN OVER THE NEXT 24 HOURS OR SO...WITH SEVERAL MODERATE
S TO SSW SWELLS EXPECTED TO PRODUCE SURF NEAR BUT LIKELY BELOW
ADVISORY LEVELS FOR MOST OF THE NEXT WEEK. HOWEVER...A PEAK ON
SUNDAY AND MONDAY COULD BRING ADVISORY LEVEL SURF TO EXPOSED S
FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 202029 CCA
AFDHFO

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE HONOLULU HI
930 AM HST WED MAY 20 2015

CORRECTED MARINE SECTION

.SYNOPSIS...
TRADE WINDS WILL DIMINISH THROUGH TONIGHT...WITH WINDS BECOMING
LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT APPROACHES THE
ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON FRIDAY...THEN
DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH SATURDAY.
NORTHEAST TRADE WINDS WILL BRIEFLY SURGE AS THE FRONT PASSES...WITH
LIGHT TO MODERATE NORTHEAST TRADE WINDS THEN PREVAILING INTO THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
CURRENTLY...MODERATE TRADE WINDS ARE BEING SUPPORTED BY A GRADUALLY
WEAKENING 1025 MB HIGH CENTERED ABOUT 800 MILES NNE OF THE ISLANDS.
ALTHOUGH THE ISLAND ATMOSPHERE REMAINS STABLE WITH A SUBSIDENCE
INVERSION BASED BETWEEN 7 AND 8 KFT...AN AREA OF SHOWERY AND STABLE
LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW HAS MADE FOR DAMP AND
SOMEWHAT CLOUDY CONDITIONS...ESPECIALLY WINDWARD. THE TRADE WINDS
ARE IN THE PROCESS OF DIMINISHING...AS A SE-WARD MOVING FRONT ABOUT
700 MILES NW OF THE ISLANDS IS FORCING THE HIGH E-WARD AND ERODING
THE WESTERN PORTION OF THE ASSOCIATED RIDGE. ISLAND SURFACE
PRESSURES ARE DOWN A MODEST 1-2 MB OVER THE PAST 24 HOURS IN
RESPONSE. THE EXPECTATION IS THAT WINDS WILL BE LIGHT ENOUGH THIS
AFTERNOON TO ALLOW CLOUDS AND ISOLATED SHOWERS TO DEVELOP OVER
LEEWARD AREAS...WHILE WINDWARD AREAS OF MOST ISLANDS WILL CONTINUE
TO SEE SOME CLOUDS...AND GRADUALLY DIMINISHING SHOWERS.

LATEST FORECAST MODELS INDICATE THAT THE WEATHER PATTERN OVER THE
ISLANDS WILL BE CHANGING IN THE SHORT TERM. A WEAK RIDGE EXTENDING
SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER THE ISLANDS ON
THURSDAY...AHEAD OF AN APPROACHING COLD FRONT. THIS WILL LEAD TO
LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-SCALE LAND AND
SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY CLEAR SKIES ARE
EXPECTED OVER THE ISLANDS BY LATE TONIGHT AND CONTINUING THROUGH
THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING OVER
INTERIOR AND MAUKA AREAS IN THE AFTERNOON. ATMOSPHERIC STABILITY
WILL REMAIN HIGH AND THUS HEAVY SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
LATEST GUIDANCE SHOWS A WEAK LOW DEVELOPING BETWEEN 28N AND 30N
THURSDAY AND FRIDAY...WHICH IS NOW EXPECTED TO PROVIDE SUFFICIENT
PUSH TO SHUNT THE FRONT DOWN THE ISLAND CHAIN...ALTHOUGH THE
WEAKENING BOUNDARY IS NOT EXPECTED TO PRODUCE WIDESPREAD RAINFALL.
WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE FRONT
PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD SLOPES
AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM THE WEEKEND INTO NEXT WEEK...AND THUS LIGHT TO
MODERATE NE TRADE WINDS ARE EXPECTED TO BRING JUST A FEW BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
TRADE WINDS WILL DECREASE FURTHER INTO THURSDAY AS A FRONT
APPROACHES FROM THE NORTHWEST AND PUSHES A RIDGE CLOSER TO THE
ISLANDS. AS FOR TODAY...NORTHEAST WINDS WILL PREVAIL AT MOST
TERMINALS WITH SELECT AREAS OF LOCALIZED SEA BREEZES. THE MORNING
SHOWER ACTIVITY ALONG WINDWARD AREAS WILL SEE IMPROVEMENT INTO THE
AFTERNOON AND THE AIRMET SIERRA FOR MOUNTAIN OBSCURATION WILL LIKELY
BE CANCELLED BY THE NEXT ROUTINE ISSUANCE AT 2200Z. OTHERWISE...NO
AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
TRADE WINDS HAVE EASED SUFFICIENTLY TO ALLOW THE FAIRLY LONG-RUNNING
SMALL CRAFT ADVISORY /SCA/ TO BE CANCELLED EARLY THIS MORNING. WINDS
AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA FOR ALL WATERS
THROUGH THE WEEKEND...AND INTO NEXT WEEK. A COUPLE OF SMALL SWELLS
FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT
WEEK...WITH RESULTANT SURF BELOW ADVISORY LEVELS. AN EXTENDED RUN OF
SURF ALONG S FACING SHORES IS POISED TO BEGIN TODAY AND TOMORROW...
WITH SEVERAL MODERATE S SWELLS EXPECTED TO PRODUCE SURF NEAR BUT
LIKELY BELOW ADVISORY LEVELS. HOWEVER...A PEAK ON SUNDAY AND MONDAY
COULD BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 202029 CCA
AFDHFO

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE HONOLULU HI
930 AM HST WED MAY 20 2015

CORRECTED MARINE SECTION

.SYNOPSIS...
TRADE WINDS WILL DIMINISH THROUGH TONIGHT...WITH WINDS BECOMING
LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT APPROACHES THE
ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON FRIDAY...THEN
DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH SATURDAY.
NORTHEAST TRADE WINDS WILL BRIEFLY SURGE AS THE FRONT PASSES...WITH
LIGHT TO MODERATE NORTHEAST TRADE WINDS THEN PREVAILING INTO THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
CURRENTLY...MODERATE TRADE WINDS ARE BEING SUPPORTED BY A GRADUALLY
WEAKENING 1025 MB HIGH CENTERED ABOUT 800 MILES NNE OF THE ISLANDS.
ALTHOUGH THE ISLAND ATMOSPHERE REMAINS STABLE WITH A SUBSIDENCE
INVERSION BASED BETWEEN 7 AND 8 KFT...AN AREA OF SHOWERY AND STABLE
LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW HAS MADE FOR DAMP AND
SOMEWHAT CLOUDY CONDITIONS...ESPECIALLY WINDWARD. THE TRADE WINDS
ARE IN THE PROCESS OF DIMINISHING...AS A SE-WARD MOVING FRONT ABOUT
700 MILES NW OF THE ISLANDS IS FORCING THE HIGH E-WARD AND ERODING
THE WESTERN PORTION OF THE ASSOCIATED RIDGE. ISLAND SURFACE
PRESSURES ARE DOWN A MODEST 1-2 MB OVER THE PAST 24 HOURS IN
RESPONSE. THE EXPECTATION IS THAT WINDS WILL BE LIGHT ENOUGH THIS
AFTERNOON TO ALLOW CLOUDS AND ISOLATED SHOWERS TO DEVELOP OVER
LEEWARD AREAS...WHILE WINDWARD AREAS OF MOST ISLANDS WILL CONTINUE
TO SEE SOME CLOUDS...AND GRADUALLY DIMINISHING SHOWERS.

LATEST FORECAST MODELS INDICATE THAT THE WEATHER PATTERN OVER THE
ISLANDS WILL BE CHANGING IN THE SHORT TERM. A WEAK RIDGE EXTENDING
SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER THE ISLANDS ON
THURSDAY...AHEAD OF AN APPROACHING COLD FRONT. THIS WILL LEAD TO
LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-SCALE LAND AND
SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY CLEAR SKIES ARE
EXPECTED OVER THE ISLANDS BY LATE TONIGHT AND CONTINUING THROUGH
THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING OVER
INTERIOR AND MAUKA AREAS IN THE AFTERNOON. ATMOSPHERIC STABILITY
WILL REMAIN HIGH AND THUS HEAVY SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
LATEST GUIDANCE SHOWS A WEAK LOW DEVELOPING BETWEEN 28N AND 30N
THURSDAY AND FRIDAY...WHICH IS NOW EXPECTED TO PROVIDE SUFFICIENT
PUSH TO SHUNT THE FRONT DOWN THE ISLAND CHAIN...ALTHOUGH THE
WEAKENING BOUNDARY IS NOT EXPECTED TO PRODUCE WIDESPREAD RAINFALL.
WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE FRONT
PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD SLOPES
AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM THE WEEKEND INTO NEXT WEEK...AND THUS LIGHT TO
MODERATE NE TRADE WINDS ARE EXPECTED TO BRING JUST A FEW BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
TRADE WINDS WILL DECREASE FURTHER INTO THURSDAY AS A FRONT
APPROACHES FROM THE NORTHWEST AND PUSHES A RIDGE CLOSER TO THE
ISLANDS. AS FOR TODAY...NORTHEAST WINDS WILL PREVAIL AT MOST
TERMINALS WITH SELECT AREAS OF LOCALIZED SEA BREEZES. THE MORNING
SHOWER ACTIVITY ALONG WINDWARD AREAS WILL SEE IMPROVEMENT INTO THE
AFTERNOON AND THE AIRMET SIERRA FOR MOUNTAIN OBSCURATION WILL LIKELY
BE CANCELLED BY THE NEXT ROUTINE ISSUANCE AT 2200Z. OTHERWISE...NO
AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
TRADE WINDS HAVE EASED SUFFICIENTLY TO ALLOW THE FAIRLY LONG-RUNNING
SMALL CRAFT ADVISORY /SCA/ TO BE CANCELLED EARLY THIS MORNING. WINDS
AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA FOR ALL WATERS
THROUGH THE WEEKEND...AND INTO NEXT WEEK. A COUPLE OF SMALL SWELLS
FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT
WEEK...WITH RESULTANT SURF BELOW ADVISORY LEVELS. AN EXTENDED RUN OF
SURF ALONG S FACING SHORES IS POISED TO BEGIN TODAY AND TOMORROW...
WITH SEVERAL MODERATE S SWELLS EXPECTED TO PRODUCE SURF NEAR BUT
LIKELY BELOW ADVISORY LEVELS. HOWEVER...A PEAK ON SUNDAY AND MONDAY
COULD BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 202029 CCA
AFDHFO

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE HONOLULU HI
930 AM HST WED MAY 20 2015

CORRECTED MARINE SECTION

.SYNOPSIS...
TRADE WINDS WILL DIMINISH THROUGH TONIGHT...WITH WINDS BECOMING
LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT APPROACHES THE
ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON FRIDAY...THEN
DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH SATURDAY.
NORTHEAST TRADE WINDS WILL BRIEFLY SURGE AS THE FRONT PASSES...WITH
LIGHT TO MODERATE NORTHEAST TRADE WINDS THEN PREVAILING INTO THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
CURRENTLY...MODERATE TRADE WINDS ARE BEING SUPPORTED BY A GRADUALLY
WEAKENING 1025 MB HIGH CENTERED ABOUT 800 MILES NNE OF THE ISLANDS.
ALTHOUGH THE ISLAND ATMOSPHERE REMAINS STABLE WITH A SUBSIDENCE
INVERSION BASED BETWEEN 7 AND 8 KFT...AN AREA OF SHOWERY AND STABLE
LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW HAS MADE FOR DAMP AND
SOMEWHAT CLOUDY CONDITIONS...ESPECIALLY WINDWARD. THE TRADE WINDS
ARE IN THE PROCESS OF DIMINISHING...AS A SE-WARD MOVING FRONT ABOUT
700 MILES NW OF THE ISLANDS IS FORCING THE HIGH E-WARD AND ERODING
THE WESTERN PORTION OF THE ASSOCIATED RIDGE. ISLAND SURFACE
PRESSURES ARE DOWN A MODEST 1-2 MB OVER THE PAST 24 HOURS IN
RESPONSE. THE EXPECTATION IS THAT WINDS WILL BE LIGHT ENOUGH THIS
AFTERNOON TO ALLOW CLOUDS AND ISOLATED SHOWERS TO DEVELOP OVER
LEEWARD AREAS...WHILE WINDWARD AREAS OF MOST ISLANDS WILL CONTINUE
TO SEE SOME CLOUDS...AND GRADUALLY DIMINISHING SHOWERS.

LATEST FORECAST MODELS INDICATE THAT THE WEATHER PATTERN OVER THE
ISLANDS WILL BE CHANGING IN THE SHORT TERM. A WEAK RIDGE EXTENDING
SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER THE ISLANDS ON
THURSDAY...AHEAD OF AN APPROACHING COLD FRONT. THIS WILL LEAD TO
LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-SCALE LAND AND
SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY CLEAR SKIES ARE
EXPECTED OVER THE ISLANDS BY LATE TONIGHT AND CONTINUING THROUGH
THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING OVER
INTERIOR AND MAUKA AREAS IN THE AFTERNOON. ATMOSPHERIC STABILITY
WILL REMAIN HIGH AND THUS HEAVY SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
LATEST GUIDANCE SHOWS A WEAK LOW DEVELOPING BETWEEN 28N AND 30N
THURSDAY AND FRIDAY...WHICH IS NOW EXPECTED TO PROVIDE SUFFICIENT
PUSH TO SHUNT THE FRONT DOWN THE ISLAND CHAIN...ALTHOUGH THE
WEAKENING BOUNDARY IS NOT EXPECTED TO PRODUCE WIDESPREAD RAINFALL.
WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE FRONT
PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD SLOPES
AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM THE WEEKEND INTO NEXT WEEK...AND THUS LIGHT TO
MODERATE NE TRADE WINDS ARE EXPECTED TO BRING JUST A FEW BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
TRADE WINDS WILL DECREASE FURTHER INTO THURSDAY AS A FRONT
APPROACHES FROM THE NORTHWEST AND PUSHES A RIDGE CLOSER TO THE
ISLANDS. AS FOR TODAY...NORTHEAST WINDS WILL PREVAIL AT MOST
TERMINALS WITH SELECT AREAS OF LOCALIZED SEA BREEZES. THE MORNING
SHOWER ACTIVITY ALONG WINDWARD AREAS WILL SEE IMPROVEMENT INTO THE
AFTERNOON AND THE AIRMET SIERRA FOR MOUNTAIN OBSCURATION WILL LIKELY
BE CANCELLED BY THE NEXT ROUTINE ISSUANCE AT 2200Z. OTHERWISE...NO
AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
TRADE WINDS HAVE EASED SUFFICIENTLY TO ALLOW THE FAIRLY LONG-RUNNING
SMALL CRAFT ADVISORY /SCA/ TO BE CANCELLED EARLY THIS MORNING. WINDS
AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA FOR ALL WATERS
THROUGH THE WEEKEND...AND INTO NEXT WEEK. A COUPLE OF SMALL SWELLS
FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT
WEEK...WITH RESULTANT SURF BELOW ADVISORY LEVELS. AN EXTENDED RUN OF
SURF ALONG S FACING SHORES IS POISED TO BEGIN TODAY AND TOMORROW...
WITH SEVERAL MODERATE S SWELLS EXPECTED TO PRODUCE SURF NEAR BUT
LIKELY BELOW ADVISORY LEVELS. HOWEVER...A PEAK ON SUNDAY AND MONDAY
COULD BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 202029 CCA
AFDHFO

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE HONOLULU HI
930 AM HST WED MAY 20 2015

CORRECTED MARINE SECTION

.SYNOPSIS...
TRADE WINDS WILL DIMINISH THROUGH TONIGHT...WITH WINDS BECOMING
LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT APPROACHES THE
ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON FRIDAY...THEN
DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH SATURDAY.
NORTHEAST TRADE WINDS WILL BRIEFLY SURGE AS THE FRONT PASSES...WITH
LIGHT TO MODERATE NORTHEAST TRADE WINDS THEN PREVAILING INTO THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
CURRENTLY...MODERATE TRADE WINDS ARE BEING SUPPORTED BY A GRADUALLY
WEAKENING 1025 MB HIGH CENTERED ABOUT 800 MILES NNE OF THE ISLANDS.
ALTHOUGH THE ISLAND ATMOSPHERE REMAINS STABLE WITH A SUBSIDENCE
INVERSION BASED BETWEEN 7 AND 8 KFT...AN AREA OF SHOWERY AND STABLE
LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW HAS MADE FOR DAMP AND
SOMEWHAT CLOUDY CONDITIONS...ESPECIALLY WINDWARD. THE TRADE WINDS
ARE IN THE PROCESS OF DIMINISHING...AS A SE-WARD MOVING FRONT ABOUT
700 MILES NW OF THE ISLANDS IS FORCING THE HIGH E-WARD AND ERODING
THE WESTERN PORTION OF THE ASSOCIATED RIDGE. ISLAND SURFACE
PRESSURES ARE DOWN A MODEST 1-2 MB OVER THE PAST 24 HOURS IN
RESPONSE. THE EXPECTATION IS THAT WINDS WILL BE LIGHT ENOUGH THIS
AFTERNOON TO ALLOW CLOUDS AND ISOLATED SHOWERS TO DEVELOP OVER
LEEWARD AREAS...WHILE WINDWARD AREAS OF MOST ISLANDS WILL CONTINUE
TO SEE SOME CLOUDS...AND GRADUALLY DIMINISHING SHOWERS.

LATEST FORECAST MODELS INDICATE THAT THE WEATHER PATTERN OVER THE
ISLANDS WILL BE CHANGING IN THE SHORT TERM. A WEAK RIDGE EXTENDING
SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER THE ISLANDS ON
THURSDAY...AHEAD OF AN APPROACHING COLD FRONT. THIS WILL LEAD TO
LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-SCALE LAND AND
SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY CLEAR SKIES ARE
EXPECTED OVER THE ISLANDS BY LATE TONIGHT AND CONTINUING THROUGH
THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING OVER
INTERIOR AND MAUKA AREAS IN THE AFTERNOON. ATMOSPHERIC STABILITY
WILL REMAIN HIGH AND THUS HEAVY SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
LATEST GUIDANCE SHOWS A WEAK LOW DEVELOPING BETWEEN 28N AND 30N
THURSDAY AND FRIDAY...WHICH IS NOW EXPECTED TO PROVIDE SUFFICIENT
PUSH TO SHUNT THE FRONT DOWN THE ISLAND CHAIN...ALTHOUGH THE
WEAKENING BOUNDARY IS NOT EXPECTED TO PRODUCE WIDESPREAD RAINFALL.
WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE FRONT
PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD SLOPES
AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM THE WEEKEND INTO NEXT WEEK...AND THUS LIGHT TO
MODERATE NE TRADE WINDS ARE EXPECTED TO BRING JUST A FEW BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
TRADE WINDS WILL DECREASE FURTHER INTO THURSDAY AS A FRONT
APPROACHES FROM THE NORTHWEST AND PUSHES A RIDGE CLOSER TO THE
ISLANDS. AS FOR TODAY...NORTHEAST WINDS WILL PREVAIL AT MOST
TERMINALS WITH SELECT AREAS OF LOCALIZED SEA BREEZES. THE MORNING
SHOWER ACTIVITY ALONG WINDWARD AREAS WILL SEE IMPROVEMENT INTO THE
AFTERNOON AND THE AIRMET SIERRA FOR MOUNTAIN OBSCURATION WILL LIKELY
BE CANCELLED BY THE NEXT ROUTINE ISSUANCE AT 2200Z. OTHERWISE...NO
AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
TRADE WINDS HAVE EASED SUFFICIENTLY TO ALLOW THE FAIRLY LONG-RUNNING
SMALL CRAFT ADVISORY /SCA/ TO BE CANCELLED EARLY THIS MORNING. WINDS
AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA FOR ALL WATERS
THROUGH THE WEEKEND...AND INTO NEXT WEEK. A COUPLE OF SMALL SWELLS
FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT
WEEK...WITH RESULTANT SURF BELOW ADVISORY LEVELS. AN EXTENDED RUN OF
SURF ALONG S FACING SHORES IS POISED TO BEGIN TODAY AND TOMORROW...
WITH SEVERAL MODERATE S SWELLS EXPECTED TO PRODUCE SURF NEAR BUT
LIKELY BELOW ADVISORY LEVELS. HOWEVER...A PEAK ON SUNDAY AND MONDAY
COULD BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 201928
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
930 AM HST WED MAY 20 2015

.SYNOPSIS...
TRADE WINDS WILL DIMINISH THROUGH TONIGHT...WITH WINDS BECOMING
LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT APPROACHES THE
ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON FRIDAY...THEN
DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH SATURDAY.
NORTHEAST TRADE WINDS WILL BRIEFLY SURGE AS THE FRONT PASSES...WITH
LIGHT TO MODERATE NORTHEAST TRADE WINDS THEN PREVAILING INTO THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
CURRENTLY...MODERATE TRADE WINDS ARE BEING SUPPORTED BY A GRADUALLY
WEAKENING 1025 MB HIGH CENTERED ABOUT 800 MILES NNE OF THE ISLANDS.
ALTHOUGH THE ISLAND ATMOSPHERE REMAINS STABLE WITH A SUBSIDENCE
INVERSION BASED BETWEEN 7 AND 8 KFT...AN AREA OF SHOWERY AND STABLE
LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW HAS MADE FOR DAMP AND
SOMEWHAT CLOUDY CONDITIONS...ESPECIALLY WINDWARD. THE TRADE WINDS
ARE IN THE PROCESS OF DIMINISHING...AS A SE-WARD MOVING FRONT ABOUT
700 MILES NW OF THE ISLANDS IS FORCING THE HIGH E-WARD AND ERODING
THE WESTERN PORTION OF THE ASSOCIATED RIDGE. ISLAND SURFACE
PRESSURES ARE DOWN A MODEST 1-2 MB OVER THE PAST 24 HOURS IN
RESPONSE. THE EXPECTATION IS THAT WINDS WILL BE LIGHT ENOUGH THIS
AFTERNOON TO ALLOW CLOUDS AND ISOLATED SHOWERS TO DEVELOP OVER
LEEWARD AREAS...WHILE WINDWARD AREAS OF MOST ISLANDS WILL CONTINUE
TO SEE SOME CLOUDS...AND GRADUALLY DIMINISHING SHOWERS.

LATEST FORECAST MODELS INDICATE THAT THE WEATHER PATTERN OVER THE
ISLANDS WILL BE CHANGING IN THE SHORT TERM. A WEAK RIDGE EXTENDING
SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER THE ISLANDS ON
THURSDAY...AHEAD OF AN APPROACHING COLD FRONT. THIS WILL LEAD TO
LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-SCALE LAND AND
SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY CLEAR SKIES ARE
EXPECTED OVER THE ISLANDS BY LATE TONIGHT AND CONTINUING THROUGH
THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING OVER
INTERIOR AND MAUKA AREAS IN THE AFTERNOON. ATMOSPHERIC STABILITY
WILL REMAIN HIGH AND THUS HEAVY SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
LATEST GUIDANCE SHOWS A WEAK LOW DEVELOPING BETWEEN 28N AND 30N
THURSDAY AND FRIDAY...WHICH IS NOW EXPECTED TO PROVIDE SUFFICIENT
PUSH TO SHUNT THE FRONT DOWN THE ISLAND CHAIN...ALTHOUGH THE
WEAKENING BOUNDARY IS NOT EXPECTED TO PRODUCE WIDESPREAD RAINFALL.
WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE FRONT
PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD SLOPES
AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM THE WEEKEND INTO NEXT WEEK...AND THUS LIGHT TO
MODERATE NE TRADE WINDS ARE EXPECTED TO BRING JUST A FEW BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
TRADE WINDS WILL DECREASE FURTHER INTO THURSDAY AS A FRONT
APPROACHES FROM THE NORTHWEST AND PUSHES A RIDGE CLOSER TO THE
ISLANDS. AS FOR TODAY...NORTHEAST WINDS WILL PREVAIL AT MOST
TERMINALS WITH SELECT AREAS OF LOCALIZED SEA BREEZES. THE MORNING
SHOWER ACTIVITY ALONG WINDWARD AREAS WILL SEE IMPROVEMENT INTO THE
AFTERNOON AND THE AIRMET SIERRA FOR MOUNTAIN OBSCURATION WILL LIKELY
BE CANCELLED BY THE NEXT ROUTINE ISSUANCE AT 2200Z. OTHERWISE...NO
AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
TRADE WINDS HAVE EASED SUFFICIENTLY TO ALLOW THE FAIRLY LONG-RUNNING
SMALL CRAFT ADVISORY /SCA/ TO BE CANCELLED EARLY THIS MORNING. WINDS
AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA FOR ALL WATERS
THROUGH THE WEEKEND...AND INTO NEXT WEEK. A COUPLE OF SMALL SWELLS
FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT
WEEK...WITH RESULTANT SURF BELOW ADVISORY LEVELS. AN EXTENDED RUN OF
SURF ALONG S FACING SHORES IS POISED TO BEGIN TODAY AND TOMORROW...
WITH SEVERAL MODERATE S SWELLS EXPECTED TO PRODUCE SURF NEAR BUT
LIKELY ADVISORY LEVELS. HOWEVER...A PEAK ON SUNDAY AND MONDAY COULD
BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







000
FXHW60 PHFO 201928
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
930 AM HST WED MAY 20 2015

.SYNOPSIS...
TRADE WINDS WILL DIMINISH THROUGH TONIGHT...WITH WINDS BECOMING
LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT APPROACHES THE
ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON FRIDAY...THEN
DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH SATURDAY.
NORTHEAST TRADE WINDS WILL BRIEFLY SURGE AS THE FRONT PASSES...WITH
LIGHT TO MODERATE NORTHEAST TRADE WINDS THEN PREVAILING INTO THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
CURRENTLY...MODERATE TRADE WINDS ARE BEING SUPPORTED BY A GRADUALLY
WEAKENING 1025 MB HIGH CENTERED ABOUT 800 MILES NNE OF THE ISLANDS.
ALTHOUGH THE ISLAND ATMOSPHERE REMAINS STABLE WITH A SUBSIDENCE
INVERSION BASED BETWEEN 7 AND 8 KFT...AN AREA OF SHOWERY AND STABLE
LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW HAS MADE FOR DAMP AND
SOMEWHAT CLOUDY CONDITIONS...ESPECIALLY WINDWARD. THE TRADE WINDS
ARE IN THE PROCESS OF DIMINISHING...AS A SE-WARD MOVING FRONT ABOUT
700 MILES NW OF THE ISLANDS IS FORCING THE HIGH E-WARD AND ERODING
THE WESTERN PORTION OF THE ASSOCIATED RIDGE. ISLAND SURFACE
PRESSURES ARE DOWN A MODEST 1-2 MB OVER THE PAST 24 HOURS IN
RESPONSE. THE EXPECTATION IS THAT WINDS WILL BE LIGHT ENOUGH THIS
AFTERNOON TO ALLOW CLOUDS AND ISOLATED SHOWERS TO DEVELOP OVER
LEEWARD AREAS...WHILE WINDWARD AREAS OF MOST ISLANDS WILL CONTINUE
TO SEE SOME CLOUDS...AND GRADUALLY DIMINISHING SHOWERS.

LATEST FORECAST MODELS INDICATE THAT THE WEATHER PATTERN OVER THE
ISLANDS WILL BE CHANGING IN THE SHORT TERM. A WEAK RIDGE EXTENDING
SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER THE ISLANDS ON
THURSDAY...AHEAD OF AN APPROACHING COLD FRONT. THIS WILL LEAD TO
LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-SCALE LAND AND
SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY CLEAR SKIES ARE
EXPECTED OVER THE ISLANDS BY LATE TONIGHT AND CONTINUING THROUGH
THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING OVER
INTERIOR AND MAUKA AREAS IN THE AFTERNOON. ATMOSPHERIC STABILITY
WILL REMAIN HIGH AND THUS HEAVY SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
LATEST GUIDANCE SHOWS A WEAK LOW DEVELOPING BETWEEN 28N AND 30N
THURSDAY AND FRIDAY...WHICH IS NOW EXPECTED TO PROVIDE SUFFICIENT
PUSH TO SHUNT THE FRONT DOWN THE ISLAND CHAIN...ALTHOUGH THE
WEAKENING BOUNDARY IS NOT EXPECTED TO PRODUCE WIDESPREAD RAINFALL.
WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE FRONT
PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD SLOPES
AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM THE WEEKEND INTO NEXT WEEK...AND THUS LIGHT TO
MODERATE NE TRADE WINDS ARE EXPECTED TO BRING JUST A FEW BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
TRADE WINDS WILL DECREASE FURTHER INTO THURSDAY AS A FRONT
APPROACHES FROM THE NORTHWEST AND PUSHES A RIDGE CLOSER TO THE
ISLANDS. AS FOR TODAY...NORTHEAST WINDS WILL PREVAIL AT MOST
TERMINALS WITH SELECT AREAS OF LOCALIZED SEA BREEZES. THE MORNING
SHOWER ACTIVITY ALONG WINDWARD AREAS WILL SEE IMPROVEMENT INTO THE
AFTERNOON AND THE AIRMET SIERRA FOR MOUNTAIN OBSCURATION WILL LIKELY
BE CANCELLED BY THE NEXT ROUTINE ISSUANCE AT 2200Z. OTHERWISE...NO
AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
TRADE WINDS HAVE EASED SUFFICIENTLY TO ALLOW THE FAIRLY LONG-RUNNING
SMALL CRAFT ADVISORY /SCA/ TO BE CANCELLED EARLY THIS MORNING. WINDS
AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA FOR ALL WATERS
THROUGH THE WEEKEND...AND INTO NEXT WEEK. A COUPLE OF SMALL SWELLS
FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT
WEEK...WITH RESULTANT SURF BELOW ADVISORY LEVELS. AN EXTENDED RUN OF
SURF ALONG S FACING SHORES IS POISED TO BEGIN TODAY AND TOMORROW...
WITH SEVERAL MODERATE S SWELLS EXPECTED TO PRODUCE SURF NEAR BUT
LIKELY ADVISORY LEVELS. HOWEVER...A PEAK ON SUNDAY AND MONDAY COULD
BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 201928
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
930 AM HST WED MAY 20 2015

.SYNOPSIS...
TRADE WINDS WILL DIMINISH THROUGH TONIGHT...WITH WINDS BECOMING
LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT APPROACHES THE
ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON FRIDAY...THEN
DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH SATURDAY.
NORTHEAST TRADE WINDS WILL BRIEFLY SURGE AS THE FRONT PASSES...WITH
LIGHT TO MODERATE NORTHEAST TRADE WINDS THEN PREVAILING INTO THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
CURRENTLY...MODERATE TRADE WINDS ARE BEING SUPPORTED BY A GRADUALLY
WEAKENING 1025 MB HIGH CENTERED ABOUT 800 MILES NNE OF THE ISLANDS.
ALTHOUGH THE ISLAND ATMOSPHERE REMAINS STABLE WITH A SUBSIDENCE
INVERSION BASED BETWEEN 7 AND 8 KFT...AN AREA OF SHOWERY AND STABLE
LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW HAS MADE FOR DAMP AND
SOMEWHAT CLOUDY CONDITIONS...ESPECIALLY WINDWARD. THE TRADE WINDS
ARE IN THE PROCESS OF DIMINISHING...AS A SE-WARD MOVING FRONT ABOUT
700 MILES NW OF THE ISLANDS IS FORCING THE HIGH E-WARD AND ERODING
THE WESTERN PORTION OF THE ASSOCIATED RIDGE. ISLAND SURFACE
PRESSURES ARE DOWN A MODEST 1-2 MB OVER THE PAST 24 HOURS IN
RESPONSE. THE EXPECTATION IS THAT WINDS WILL BE LIGHT ENOUGH THIS
AFTERNOON TO ALLOW CLOUDS AND ISOLATED SHOWERS TO DEVELOP OVER
LEEWARD AREAS...WHILE WINDWARD AREAS OF MOST ISLANDS WILL CONTINUE
TO SEE SOME CLOUDS...AND GRADUALLY DIMINISHING SHOWERS.

LATEST FORECAST MODELS INDICATE THAT THE WEATHER PATTERN OVER THE
ISLANDS WILL BE CHANGING IN THE SHORT TERM. A WEAK RIDGE EXTENDING
SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER THE ISLANDS ON
THURSDAY...AHEAD OF AN APPROACHING COLD FRONT. THIS WILL LEAD TO
LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-SCALE LAND AND
SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY CLEAR SKIES ARE
EXPECTED OVER THE ISLANDS BY LATE TONIGHT AND CONTINUING THROUGH
THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING OVER
INTERIOR AND MAUKA AREAS IN THE AFTERNOON. ATMOSPHERIC STABILITY
WILL REMAIN HIGH AND THUS HEAVY SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
LATEST GUIDANCE SHOWS A WEAK LOW DEVELOPING BETWEEN 28N AND 30N
THURSDAY AND FRIDAY...WHICH IS NOW EXPECTED TO PROVIDE SUFFICIENT
PUSH TO SHUNT THE FRONT DOWN THE ISLAND CHAIN...ALTHOUGH THE
WEAKENING BOUNDARY IS NOT EXPECTED TO PRODUCE WIDESPREAD RAINFALL.
WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE FRONT
PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD SLOPES
AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM THE WEEKEND INTO NEXT WEEK...AND THUS LIGHT TO
MODERATE NE TRADE WINDS ARE EXPECTED TO BRING JUST A FEW BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
TRADE WINDS WILL DECREASE FURTHER INTO THURSDAY AS A FRONT
APPROACHES FROM THE NORTHWEST AND PUSHES A RIDGE CLOSER TO THE
ISLANDS. AS FOR TODAY...NORTHEAST WINDS WILL PREVAIL AT MOST
TERMINALS WITH SELECT AREAS OF LOCALIZED SEA BREEZES. THE MORNING
SHOWER ACTIVITY ALONG WINDWARD AREAS WILL SEE IMPROVEMENT INTO THE
AFTERNOON AND THE AIRMET SIERRA FOR MOUNTAIN OBSCURATION WILL LIKELY
BE CANCELLED BY THE NEXT ROUTINE ISSUANCE AT 2200Z. OTHERWISE...NO
AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
TRADE WINDS HAVE EASED SUFFICIENTLY TO ALLOW THE FAIRLY LONG-RUNNING
SMALL CRAFT ADVISORY /SCA/ TO BE CANCELLED EARLY THIS MORNING. WINDS
AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA FOR ALL WATERS
THROUGH THE WEEKEND...AND INTO NEXT WEEK. A COUPLE OF SMALL SWELLS
FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT
WEEK...WITH RESULTANT SURF BELOW ADVISORY LEVELS. AN EXTENDED RUN OF
SURF ALONG S FACING SHORES IS POISED TO BEGIN TODAY AND TOMORROW...
WITH SEVERAL MODERATE S SWELLS EXPECTED TO PRODUCE SURF NEAR BUT
LIKELY ADVISORY LEVELS. HOWEVER...A PEAK ON SUNDAY AND MONDAY COULD
BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON






000
FXHW60 PHFO 201928
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
930 AM HST WED MAY 20 2015

.SYNOPSIS...
TRADE WINDS WILL DIMINISH THROUGH TONIGHT...WITH WINDS BECOMING
LIGHT AND VARIABLE ON THURSDAY...AS A WEAK FRONT APPROACHES THE
ISLANDS. THE FRONT IS EXPECTED TO REACH KAUAI ON FRIDAY...THEN
DISSIPATE AS IT MOVES DOWN THE ISLAND CHAIN THROUGH SATURDAY.
NORTHEAST TRADE WINDS WILL BRIEFLY SURGE AS THE FRONT PASSES...WITH
LIGHT TO MODERATE NORTHEAST TRADE WINDS THEN PREVAILING INTO THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
CURRENTLY...MODERATE TRADE WINDS ARE BEING SUPPORTED BY A GRADUALLY
WEAKENING 1025 MB HIGH CENTERED ABOUT 800 MILES NNE OF THE ISLANDS.
ALTHOUGH THE ISLAND ATMOSPHERE REMAINS STABLE WITH A SUBSIDENCE
INVERSION BASED BETWEEN 7 AND 8 KFT...AN AREA OF SHOWERY AND STABLE
LOW CLOUDS EMBEDDED IN THE TRADE WIND FLOW HAS MADE FOR DAMP AND
SOMEWHAT CLOUDY CONDITIONS...ESPECIALLY WINDWARD. THE TRADE WINDS
ARE IN THE PROCESS OF DIMINISHING...AS A SE-WARD MOVING FRONT ABOUT
700 MILES NW OF THE ISLANDS IS FORCING THE HIGH E-WARD AND ERODING
THE WESTERN PORTION OF THE ASSOCIATED RIDGE. ISLAND SURFACE
PRESSURES ARE DOWN A MODEST 1-2 MB OVER THE PAST 24 HOURS IN
RESPONSE. THE EXPECTATION IS THAT WINDS WILL BE LIGHT ENOUGH THIS
AFTERNOON TO ALLOW CLOUDS AND ISOLATED SHOWERS TO DEVELOP OVER
LEEWARD AREAS...WHILE WINDWARD AREAS OF MOST ISLANDS WILL CONTINUE
TO SEE SOME CLOUDS...AND GRADUALLY DIMINISHING SHOWERS.

LATEST FORECAST MODELS INDICATE THAT THE WEATHER PATTERN OVER THE
ISLANDS WILL BE CHANGING IN THE SHORT TERM. A WEAK RIDGE EXTENDING
SW FROM THE HIGH WILL BE BRIEFLY PUSHED OVER THE ISLANDS ON
THURSDAY...AHEAD OF AN APPROACHING COLD FRONT. THIS WILL LEAD TO
LIGHT AND VARIABLE WINDS...WHICH WILL ALLOW ISLAND-SCALE LAND AND
SEA BREEZES TO DOMINATE ISLAND WEATHER. THUS MOSTLY CLEAR SKIES ARE
EXPECTED OVER THE ISLANDS BY LATE TONIGHT AND CONTINUING THROUGH
THURSDAY MORNING...WITH CLOUDS AND A FEW SHOWERS DEVELOPING OVER
INTERIOR AND MAUKA AREAS IN THE AFTERNOON. ATMOSPHERIC STABILITY
WILL REMAIN HIGH AND THUS HEAVY SHOWERS ARE NOT EXPECTED.

THE RIDGE WILL GET PUSHED SE OF THE ISLANDS ON THURSDAY NIGHT...WITH
A BRIEF PERIOD OF LIGHT W/SW WINDS EXPECTED JUST AHEAD OF THE FRONT.
LATEST GUIDANCE SHOWS A WEAK LOW DEVELOPING BETWEEN 28N AND 30N
THURSDAY AND FRIDAY...WHICH IS NOW EXPECTED TO PROVIDE SUFFICIENT
PUSH TO SHUNT THE FRONT DOWN THE ISLAND CHAIN...ALTHOUGH THE
WEAKENING BOUNDARY IS NOT EXPECTED TO PRODUCE WIDESPREAD RAINFALL.
WINDS WILL TURN TO THE N AND NE AND BRIEFLY SURGE AS THE FRONT
PASSES...THUS FOCUSING MOST OF THE MOISTURE ALONG WINDWARD SLOPES
AND COASTS.

THE LOW WILL LINGER TO THE NE OF THE ISLANDS AS HIGH PRESSURE BUILDS
NW OF THE AREA FROM THE WEEKEND INTO NEXT WEEK...AND THUS LIGHT TO
MODERATE NE TRADE WINDS ARE EXPECTED TO BRING JUST A FEW BRIEF
WINDWARD SHOWERS THAT WILL BE MOST ACTIVE NIGHTS AND MORNINGS.

&&

.AVIATION...
TRADE WINDS WILL DECREASE FURTHER INTO THURSDAY AS A FRONT
APPROACHES FROM THE NORTHWEST AND PUSHES A RIDGE CLOSER TO THE
ISLANDS. AS FOR TODAY...NORTHEAST WINDS WILL PREVAIL AT MOST
TERMINALS WITH SELECT AREAS OF LOCALIZED SEA BREEZES. THE MORNING
SHOWER ACTIVITY ALONG WINDWARD AREAS WILL SEE IMPROVEMENT INTO THE
AFTERNOON AND THE AIRMET SIERRA FOR MOUNTAIN OBSCURATION WILL LIKELY
BE CANCELLED BY THE NEXT ROUTINE ISSUANCE AT 2200Z. OTHERWISE...NO
AIRMETS ARE EXPECTED FOR THE PERIOD.

&&

.MARINE...
TRADE WINDS HAVE EASED SUFFICIENTLY TO ALLOW THE FAIRLY LONG-RUNNING
SMALL CRAFT ADVISORY /SCA/ TO BE CANCELLED EARLY THIS MORNING. WINDS
AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA FOR ALL WATERS
THROUGH THE WEEKEND...AND INTO NEXT WEEK. A COUPLE OF SMALL SWELLS
FROM THE NNW AND WNW ARE EXPECTED OVER THE WEEKEND AND EARLY NEXT
WEEK...WITH RESULTANT SURF BELOW ADVISORY LEVELS. AN EXTENDED RUN OF
SURF ALONG S FACING SHORES IS POISED TO BEGIN TODAY AND TOMORROW...
WITH SEVERAL MODERATE S SWELLS EXPECTED TO PRODUCE SURF NEAR BUT
LIKELY ADVISORY LEVELS. HOWEVER...A PEAK ON SUNDAY AND MONDAY COULD
BRING ADVISORY LEVEL SURF TO EXPOSED S FACING SHORES.

&&

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

&&

$$

DISCUSSION/MARINE...BIRCHARD
AVIATION...EATON







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