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000
FXHW60 PHFO 020125
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST WED APR 1 2015

.SYNOPSIS...
A HIGH NORTHEAST OF THE ISLANDS WILL KEEP TRADE WINDS BLOWING OVER
THE AREA. SHOWERS WILL BECOME MORE ACTIVE STARTING TOMORROW AND
REMAIN ACTIVE THROUGH THE WEEKEND AS TROPICAL MOISTURE SPREADS OVER
THE ISLANDS FROM THE SOUTHEAST. THE WINDWARD SIDE OF THE BIG ISLAND
WILL GET THE MOST RAIN. IT WILL TURN DRIER AND BREEZIER EARLY NEXT
WEEK AS A NEW HIGH BUILDS NORTH OF THE AREA AND THE TROPICAL
MOISTURE MOVES AWAY TO THE WEST.

&&

.DISCUSSION...
HIGH PRESSURE CONTINUES TO DOMINATE MOST OF THE NORTH CENTRAL
PACIFIC. A 1035 MB HIGH FAR NORTHEAST OF THE ISLANDS IS PRODUCING
LOCALLY BREEZY TRADE WINDS OVER MOST OF THE AREA BUT A WEAK NORTH TO
SOUTH TROUGH IS KEEPING WIND SPEEDS LIGHTER NEAR KAUAI. THE WEATHER
WILL BE GENERALLY DRY THIS EVENING BUT MOISTURE ASSOCIATED WITH THE
TROUGH WILL KEEP KAUAI A BIT WET. THE TROUGH WILL MOVE AWAY TO THE
NORTHWEST TONIGHT AND DRY TRADE-WIND WEATHER WILL PREVAIL THROUGH
TOMORROW.

SATELLITE LOOPS SHOW AN AREA OF LAYERED CLOUDS AND ISOLATED
THUNDERSTORMS AROUND 300 MILES SOUTHEAST OF THE BIG ISLAND
ASSOCIATED WITH A WEAK TROPICAL DISTURBANCE. THE COMPUTER MODELS
SHOW SOME OF THIS MOISTURE MOVING OVER THE ISLANDS STARTING TOMORROW
EVENING BUT THE MODELS STILL DISAGREE ON THE DETAILS. WE EXPECT THE
MOISTURE TO REACH THE BIG ISLAND TOMORROW EVENING AND SPREAD TO
KAUAI BY SATURDAY MORNING. THE BIGGEST IMPACT WILL BE ON THE BIG
ISLAND WHERE THE MOISTURE MAY BE DEEP ENOUGH TO BRING SNOW TO THE
SUMMITS OF MAUNA KEA AND MAUNA LOA. OAHU AND KAUAI WILL SEE ONLY A
MODEST INCREASE IN SHOWERS. SURFACE HIGH PRESSURE NORTHEAST OF THE
AREA WILL KEEP EAST TO EAST SOUTHEAST TRADE WINDS BLOWING ACROSS THE
AREA SO SHOWERS WILL BE FOCUSED OVER WINDWARD AREAS. THE MOISTURE
WILL MOVE OFF TO THE WEST BY SUNDAY NIGHT AND WINDWARD SHOWERS WILL
DECREASE.

&&

.AVIATION...
STRONG TRADE WINDS WILL PRODUCE TEMP MOD TURB SOUTHWEST OF THE
ISLANDS BELOW 8000 FT AND AIRMET TANGO IS IN EFFECT FROM THE BIG
ISLAND TO OAHU FOR THIS TURBULENCE. VFR CONDITIONS WILL PREVAIL...
BUT ISOLATED MVFR CONDITIONS ARE POSSIBLE...MAINLY OVER WINDWARD
AREAS AND OVER CENTRAL LANAI.

&&

.MARINE...
A SMALL CRAFT ADVISORY CONTINUES FOR THE WINDIER WATERS AROUND THE
BIG ISLAND AND MAUI COUNTY DUE TO STRONG EASTERLY TRADE WINDS. A
TROUGH MAY DROP THE WINDS BELOW THE ADVISORY LEVEL ON FRIDAY. WINDS
WILL LIKELY BE BACK UP TO ADVISORY LEVELS AROUND MAUI AND THE BIG
ISLAND BY SATURDAY.

A LONG FETCH OF FRESH TO STRONG TRADE WINDS EAST OF THE ISLANDS WILL
BOOST SURF ALONG EAST FACING SHORES OVER THE WEEKEND. SURF MAY
APPROACH THE ADVISORY LEVEL ALONG THE EAST FACING SHORES SUNDAY AND
MONDAY.  A SERIES OF SMALL NORTHWEST AND SOUTH SWELLS WILL
CONTINUE...BUT SURF IS EXPECTED TO REMAIN BELOW THE ADVISORY
THRESHOLDS ALONG SOUTH...WEST AND NORTH FACING SHORES.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 600 AM FRIDAY FOR MAALAEA BAY...THE
PAILOLO AND ALENUIHAHA CHANNELS AND WATERS SOUTH OF THE BIG ISLAND.

&&

$$
DONALDSON







000
FXHW60 PHFO 020125
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST WED APR 1 2015

.SYNOPSIS...
A HIGH NORTHEAST OF THE ISLANDS WILL KEEP TRADE WINDS BLOWING OVER
THE AREA. SHOWERS WILL BECOME MORE ACTIVE STARTING TOMORROW AND
REMAIN ACTIVE THROUGH THE WEEKEND AS TROPICAL MOISTURE SPREADS OVER
THE ISLANDS FROM THE SOUTHEAST. THE WINDWARD SIDE OF THE BIG ISLAND
WILL GET THE MOST RAIN. IT WILL TURN DRIER AND BREEZIER EARLY NEXT
WEEK AS A NEW HIGH BUILDS NORTH OF THE AREA AND THE TROPICAL
MOISTURE MOVES AWAY TO THE WEST.

&&

.DISCUSSION...
HIGH PRESSURE CONTINUES TO DOMINATE MOST OF THE NORTH CENTRAL
PACIFIC. A 1035 MB HIGH FAR NORTHEAST OF THE ISLANDS IS PRODUCING
LOCALLY BREEZY TRADE WINDS OVER MOST OF THE AREA BUT A WEAK NORTH TO
SOUTH TROUGH IS KEEPING WIND SPEEDS LIGHTER NEAR KAUAI. THE WEATHER
WILL BE GENERALLY DRY THIS EVENING BUT MOISTURE ASSOCIATED WITH THE
TROUGH WILL KEEP KAUAI A BIT WET. THE TROUGH WILL MOVE AWAY TO THE
NORTHWEST TONIGHT AND DRY TRADE-WIND WEATHER WILL PREVAIL THROUGH
TOMORROW.

SATELLITE LOOPS SHOW AN AREA OF LAYERED CLOUDS AND ISOLATED
THUNDERSTORMS AROUND 300 MILES SOUTHEAST OF THE BIG ISLAND
ASSOCIATED WITH A WEAK TROPICAL DISTURBANCE. THE COMPUTER MODELS
SHOW SOME OF THIS MOISTURE MOVING OVER THE ISLANDS STARTING TOMORROW
EVENING BUT THE MODELS STILL DISAGREE ON THE DETAILS. WE EXPECT THE
MOISTURE TO REACH THE BIG ISLAND TOMORROW EVENING AND SPREAD TO
KAUAI BY SATURDAY MORNING. THE BIGGEST IMPACT WILL BE ON THE BIG
ISLAND WHERE THE MOISTURE MAY BE DEEP ENOUGH TO BRING SNOW TO THE
SUMMITS OF MAUNA KEA AND MAUNA LOA. OAHU AND KAUAI WILL SEE ONLY A
MODEST INCREASE IN SHOWERS. SURFACE HIGH PRESSURE NORTHEAST OF THE
AREA WILL KEEP EAST TO EAST SOUTHEAST TRADE WINDS BLOWING ACROSS THE
AREA SO SHOWERS WILL BE FOCUSED OVER WINDWARD AREAS. THE MOISTURE
WILL MOVE OFF TO THE WEST BY SUNDAY NIGHT AND WINDWARD SHOWERS WILL
DECREASE.

&&

.AVIATION...
STRONG TRADE WINDS WILL PRODUCE TEMP MOD TURB SOUTHWEST OF THE
ISLANDS BELOW 8000 FT AND AIRMET TANGO IS IN EFFECT FROM THE BIG
ISLAND TO OAHU FOR THIS TURBULENCE. VFR CONDITIONS WILL PREVAIL...
BUT ISOLATED MVFR CONDITIONS ARE POSSIBLE...MAINLY OVER WINDWARD
AREAS AND OVER CENTRAL LANAI.

&&

.MARINE...
A SMALL CRAFT ADVISORY CONTINUES FOR THE WINDIER WATERS AROUND THE
BIG ISLAND AND MAUI COUNTY DUE TO STRONG EASTERLY TRADE WINDS. A
TROUGH MAY DROP THE WINDS BELOW THE ADVISORY LEVEL ON FRIDAY. WINDS
WILL LIKELY BE BACK UP TO ADVISORY LEVELS AROUND MAUI AND THE BIG
ISLAND BY SATURDAY.

A LONG FETCH OF FRESH TO STRONG TRADE WINDS EAST OF THE ISLANDS WILL
BOOST SURF ALONG EAST FACING SHORES OVER THE WEEKEND. SURF MAY
APPROACH THE ADVISORY LEVEL ALONG THE EAST FACING SHORES SUNDAY AND
MONDAY.  A SERIES OF SMALL NORTHWEST AND SOUTH SWELLS WILL
CONTINUE...BUT SURF IS EXPECTED TO REMAIN BELOW THE ADVISORY
THRESHOLDS ALONG SOUTH...WEST AND NORTH FACING SHORES.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 600 AM FRIDAY FOR MAALAEA BAY...THE
PAILOLO AND ALENUIHAHA CHANNELS AND WATERS SOUTH OF THE BIG ISLAND.

&&

$$
DONALDSON






000
FXHW60 PHFO 020125
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST WED APR 1 2015

.SYNOPSIS...
A HIGH NORTHEAST OF THE ISLANDS WILL KEEP TRADE WINDS BLOWING OVER
THE AREA. SHOWERS WILL BECOME MORE ACTIVE STARTING TOMORROW AND
REMAIN ACTIVE THROUGH THE WEEKEND AS TROPICAL MOISTURE SPREADS OVER
THE ISLANDS FROM THE SOUTHEAST. THE WINDWARD SIDE OF THE BIG ISLAND
WILL GET THE MOST RAIN. IT WILL TURN DRIER AND BREEZIER EARLY NEXT
WEEK AS A NEW HIGH BUILDS NORTH OF THE AREA AND THE TROPICAL
MOISTURE MOVES AWAY TO THE WEST.

&&

.DISCUSSION...
HIGH PRESSURE CONTINUES TO DOMINATE MOST OF THE NORTH CENTRAL
PACIFIC. A 1035 MB HIGH FAR NORTHEAST OF THE ISLANDS IS PRODUCING
LOCALLY BREEZY TRADE WINDS OVER MOST OF THE AREA BUT A WEAK NORTH TO
SOUTH TROUGH IS KEEPING WIND SPEEDS LIGHTER NEAR KAUAI. THE WEATHER
WILL BE GENERALLY DRY THIS EVENING BUT MOISTURE ASSOCIATED WITH THE
TROUGH WILL KEEP KAUAI A BIT WET. THE TROUGH WILL MOVE AWAY TO THE
NORTHWEST TONIGHT AND DRY TRADE-WIND WEATHER WILL PREVAIL THROUGH
TOMORROW.

SATELLITE LOOPS SHOW AN AREA OF LAYERED CLOUDS AND ISOLATED
THUNDERSTORMS AROUND 300 MILES SOUTHEAST OF THE BIG ISLAND
ASSOCIATED WITH A WEAK TROPICAL DISTURBANCE. THE COMPUTER MODELS
SHOW SOME OF THIS MOISTURE MOVING OVER THE ISLANDS STARTING TOMORROW
EVENING BUT THE MODELS STILL DISAGREE ON THE DETAILS. WE EXPECT THE
MOISTURE TO REACH THE BIG ISLAND TOMORROW EVENING AND SPREAD TO
KAUAI BY SATURDAY MORNING. THE BIGGEST IMPACT WILL BE ON THE BIG
ISLAND WHERE THE MOISTURE MAY BE DEEP ENOUGH TO BRING SNOW TO THE
SUMMITS OF MAUNA KEA AND MAUNA LOA. OAHU AND KAUAI WILL SEE ONLY A
MODEST INCREASE IN SHOWERS. SURFACE HIGH PRESSURE NORTHEAST OF THE
AREA WILL KEEP EAST TO EAST SOUTHEAST TRADE WINDS BLOWING ACROSS THE
AREA SO SHOWERS WILL BE FOCUSED OVER WINDWARD AREAS. THE MOISTURE
WILL MOVE OFF TO THE WEST BY SUNDAY NIGHT AND WINDWARD SHOWERS WILL
DECREASE.

&&

.AVIATION...
STRONG TRADE WINDS WILL PRODUCE TEMP MOD TURB SOUTHWEST OF THE
ISLANDS BELOW 8000 FT AND AIRMET TANGO IS IN EFFECT FROM THE BIG
ISLAND TO OAHU FOR THIS TURBULENCE. VFR CONDITIONS WILL PREVAIL...
BUT ISOLATED MVFR CONDITIONS ARE POSSIBLE...MAINLY OVER WINDWARD
AREAS AND OVER CENTRAL LANAI.

&&

.MARINE...
A SMALL CRAFT ADVISORY CONTINUES FOR THE WINDIER WATERS AROUND THE
BIG ISLAND AND MAUI COUNTY DUE TO STRONG EASTERLY TRADE WINDS. A
TROUGH MAY DROP THE WINDS BELOW THE ADVISORY LEVEL ON FRIDAY. WINDS
WILL LIKELY BE BACK UP TO ADVISORY LEVELS AROUND MAUI AND THE BIG
ISLAND BY SATURDAY.

A LONG FETCH OF FRESH TO STRONG TRADE WINDS EAST OF THE ISLANDS WILL
BOOST SURF ALONG EAST FACING SHORES OVER THE WEEKEND. SURF MAY
APPROACH THE ADVISORY LEVEL ALONG THE EAST FACING SHORES SUNDAY AND
MONDAY.  A SERIES OF SMALL NORTHWEST AND SOUTH SWELLS WILL
CONTINUE...BUT SURF IS EXPECTED TO REMAIN BELOW THE ADVISORY
THRESHOLDS ALONG SOUTH...WEST AND NORTH FACING SHORES.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 600 AM FRIDAY FOR MAALAEA BAY...THE
PAILOLO AND ALENUIHAHA CHANNELS AND WATERS SOUTH OF THE BIG ISLAND.

&&

$$
DONALDSON







000
FXHW60 PHFO 020125
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST WED APR 1 2015

.SYNOPSIS...
A HIGH NORTHEAST OF THE ISLANDS WILL KEEP TRADE WINDS BLOWING OVER
THE AREA. SHOWERS WILL BECOME MORE ACTIVE STARTING TOMORROW AND
REMAIN ACTIVE THROUGH THE WEEKEND AS TROPICAL MOISTURE SPREADS OVER
THE ISLANDS FROM THE SOUTHEAST. THE WINDWARD SIDE OF THE BIG ISLAND
WILL GET THE MOST RAIN. IT WILL TURN DRIER AND BREEZIER EARLY NEXT
WEEK AS A NEW HIGH BUILDS NORTH OF THE AREA AND THE TROPICAL
MOISTURE MOVES AWAY TO THE WEST.

&&

.DISCUSSION...
HIGH PRESSURE CONTINUES TO DOMINATE MOST OF THE NORTH CENTRAL
PACIFIC. A 1035 MB HIGH FAR NORTHEAST OF THE ISLANDS IS PRODUCING
LOCALLY BREEZY TRADE WINDS OVER MOST OF THE AREA BUT A WEAK NORTH TO
SOUTH TROUGH IS KEEPING WIND SPEEDS LIGHTER NEAR KAUAI. THE WEATHER
WILL BE GENERALLY DRY THIS EVENING BUT MOISTURE ASSOCIATED WITH THE
TROUGH WILL KEEP KAUAI A BIT WET. THE TROUGH WILL MOVE AWAY TO THE
NORTHWEST TONIGHT AND DRY TRADE-WIND WEATHER WILL PREVAIL THROUGH
TOMORROW.

SATELLITE LOOPS SHOW AN AREA OF LAYERED CLOUDS AND ISOLATED
THUNDERSTORMS AROUND 300 MILES SOUTHEAST OF THE BIG ISLAND
ASSOCIATED WITH A WEAK TROPICAL DISTURBANCE. THE COMPUTER MODELS
SHOW SOME OF THIS MOISTURE MOVING OVER THE ISLANDS STARTING TOMORROW
EVENING BUT THE MODELS STILL DISAGREE ON THE DETAILS. WE EXPECT THE
MOISTURE TO REACH THE BIG ISLAND TOMORROW EVENING AND SPREAD TO
KAUAI BY SATURDAY MORNING. THE BIGGEST IMPACT WILL BE ON THE BIG
ISLAND WHERE THE MOISTURE MAY BE DEEP ENOUGH TO BRING SNOW TO THE
SUMMITS OF MAUNA KEA AND MAUNA LOA. OAHU AND KAUAI WILL SEE ONLY A
MODEST INCREASE IN SHOWERS. SURFACE HIGH PRESSURE NORTHEAST OF THE
AREA WILL KEEP EAST TO EAST SOUTHEAST TRADE WINDS BLOWING ACROSS THE
AREA SO SHOWERS WILL BE FOCUSED OVER WINDWARD AREAS. THE MOISTURE
WILL MOVE OFF TO THE WEST BY SUNDAY NIGHT AND WINDWARD SHOWERS WILL
DECREASE.

&&

.AVIATION...
STRONG TRADE WINDS WILL PRODUCE TEMP MOD TURB SOUTHWEST OF THE
ISLANDS BELOW 8000 FT AND AIRMET TANGO IS IN EFFECT FROM THE BIG
ISLAND TO OAHU FOR THIS TURBULENCE. VFR CONDITIONS WILL PREVAIL...
BUT ISOLATED MVFR CONDITIONS ARE POSSIBLE...MAINLY OVER WINDWARD
AREAS AND OVER CENTRAL LANAI.

&&

.MARINE...
A SMALL CRAFT ADVISORY CONTINUES FOR THE WINDIER WATERS AROUND THE
BIG ISLAND AND MAUI COUNTY DUE TO STRONG EASTERLY TRADE WINDS. A
TROUGH MAY DROP THE WINDS BELOW THE ADVISORY LEVEL ON FRIDAY. WINDS
WILL LIKELY BE BACK UP TO ADVISORY LEVELS AROUND MAUI AND THE BIG
ISLAND BY SATURDAY.

A LONG FETCH OF FRESH TO STRONG TRADE WINDS EAST OF THE ISLANDS WILL
BOOST SURF ALONG EAST FACING SHORES OVER THE WEEKEND. SURF MAY
APPROACH THE ADVISORY LEVEL ALONG THE EAST FACING SHORES SUNDAY AND
MONDAY.  A SERIES OF SMALL NORTHWEST AND SOUTH SWELLS WILL
CONTINUE...BUT SURF IS EXPECTED TO REMAIN BELOW THE ADVISORY
THRESHOLDS ALONG SOUTH...WEST AND NORTH FACING SHORES.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 600 AM FRIDAY FOR MAALAEA BAY...THE
PAILOLO AND ALENUIHAHA CHANNELS AND WATERS SOUTH OF THE BIG ISLAND.

&&

$$
DONALDSON






000
FXHW60 PHFO 012010
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST WED APR 1 2015

.SYNOPSIS...
A HIGH TO THE NORTHEAST WILL KEEP TRADE WINDS BLOWING OVER THE AREA
BUT A TROUGH WILL KEEP WINDS LIGHT NEAR KAUAI. SHOWERS WILL BECOME
MORE ACTIVE STARTING TOMORROW AS TROPICAL MOISTURE SPREADS OVER THE
ISLANDS FROM THE SOUTHEAST. IT WILL TURN DRIER AND BREEZIER EARLY
NEXT WEEK AS A NEW HIGH BUILDS NORTH OF THE AREA AND THE TROPICAL
MOISTURE MOVES AWAY TO THE WEST.

&&

.DISCUSSION...
HIGH PRESSURE DOMINATES MOST OF THE NORTH CENTRAL PACIFIC. A 1035 MB
HIGH FAR NORTHEAST OF THE ISLANDS IS PRODUCING LOCALLY BREEZY TRADE
WINDS OVER MOST OF THE AREA BUT A WEAK NORTH TO SOUTH TROUGH IS
KEEPING WIND SPEEDS LIGHT NEAR KAUAI. MOISTURE ASSOCIATED WITH THE
TROUGH IS MOVING OFF TO THE NORTHWEST TODAY...SO DRY TRADE-WIND
WEATHER WILL PREVAIL THROUGH TOMORROW.

SATELLITE LOOPS SHOW AN AREA OF LAYERED CLOUDS AND ISOLATED
THUNDERSTORMS AROUND 300 MILES SOUTHEAST OF THE BIG ISLAND. THESE
CLOUDS ARE ASSOCIATED WITH A WEAK TROPICAL DISTURBANCE. AFTER DAYS
OF WIDELY DIFFERING FORECASTS THE GLOBAL MODELS HAVE BECOME INTO
MUCH BETTER AGREEMENT THIS MORNING. THE MODELS SHOW THE TROPICAL
MOISTURE REACHING THE BIG ISLAND TOMORROW EVENING AND SPREADING TO
KAUAI BY SATURDAY MORNING THIS MOISTURE WILL BRING AN INCREASE IN
RAINFALL ACROSS THE ISLANDS. SURFACE HIGH PRESSURE NORTHEAST OF THE
AREA WILL KEEP EAST TO EAST SOUTHEAST TRADE WINDS BLOWING ACROSS THE
AREA SO SHOWERS WILL BE FOCUSED OVER WINDWARD AREAS. THE MOISTURE
WILL MOVE OFF TO THE WEST BY SUNDAY NIGHT AND WINDWARD SHOWERS WILL
DECREASE.

&&

.AVIATION...
STRONG TRADE WINDS WILL PRODUCE TEMP MOD TURB SOUTHWEST OF THE
ISLANDS BELOW 8000 FT AND AIRMET TANGO IS IN EFFECT FOR THIS
TURBULENCE. VFR CONDITIONS WILL PREVAIL...BUT ISOLATED MVFR
CONDITIONS ARE POSSIBLE...MAINLY OVER WINDWARD AREAS AND OVER
CENTRAL LANAI.

&&

.MARINE...
A SMALL CRAFT ADVISORY CONTINUES FOR THE WINDIER WATERS AROUND THE
BIG ISLAND AND MAUI COUNTY DUE TO STRONG EASTERLY TRADE WINDS. A
TROUGH MAY DROP THE WINDS BELOW THE ADVISORY LEVEL ON FRIDAY. WINDS
WILL LIKELY BE BACK UP TO ADVISORY LEVELS MAUI BY SATURDAY.

A LONG FETCH OF FRESH TO STRONG TRADE WINDS EAST OF THE ISLANDS WILL
BOOST SURF ALONG EAST FACING SHORES THROUGH EARLY NEXT WEEK AND A
SERIES OF SMALL NORTHWEST AND SOUTH SWELLS WILL CONTINUE...BUT SURF
IS EXPECTED TO REMAIN BELOW THE ADVISORY THRESHOLDS FOR THE NEXT
SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 600 PM THURSDAY FOR MAALAEA BAY...THE
PAILOLO AND ALENUIHAHA CHANNELS AND WATERS SOUTH OF THE BIG ISLAND.

&&

$$
DONALDSON








000
FXHW60 PHFO 012010
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST WED APR 1 2015

.SYNOPSIS...
A HIGH TO THE NORTHEAST WILL KEEP TRADE WINDS BLOWING OVER THE AREA
BUT A TROUGH WILL KEEP WINDS LIGHT NEAR KAUAI. SHOWERS WILL BECOME
MORE ACTIVE STARTING TOMORROW AS TROPICAL MOISTURE SPREADS OVER THE
ISLANDS FROM THE SOUTHEAST. IT WILL TURN DRIER AND BREEZIER EARLY
NEXT WEEK AS A NEW HIGH BUILDS NORTH OF THE AREA AND THE TROPICAL
MOISTURE MOVES AWAY TO THE WEST.

&&

.DISCUSSION...
HIGH PRESSURE DOMINATES MOST OF THE NORTH CENTRAL PACIFIC. A 1035 MB
HIGH FAR NORTHEAST OF THE ISLANDS IS PRODUCING LOCALLY BREEZY TRADE
WINDS OVER MOST OF THE AREA BUT A WEAK NORTH TO SOUTH TROUGH IS
KEEPING WIND SPEEDS LIGHT NEAR KAUAI. MOISTURE ASSOCIATED WITH THE
TROUGH IS MOVING OFF TO THE NORTHWEST TODAY...SO DRY TRADE-WIND
WEATHER WILL PREVAIL THROUGH TOMORROW.

SATELLITE LOOPS SHOW AN AREA OF LAYERED CLOUDS AND ISOLATED
THUNDERSTORMS AROUND 300 MILES SOUTHEAST OF THE BIG ISLAND. THESE
CLOUDS ARE ASSOCIATED WITH A WEAK TROPICAL DISTURBANCE. AFTER DAYS
OF WIDELY DIFFERING FORECASTS THE GLOBAL MODELS HAVE BECOME INTO
MUCH BETTER AGREEMENT THIS MORNING. THE MODELS SHOW THE TROPICAL
MOISTURE REACHING THE BIG ISLAND TOMORROW EVENING AND SPREADING TO
KAUAI BY SATURDAY MORNING THIS MOISTURE WILL BRING AN INCREASE IN
RAINFALL ACROSS THE ISLANDS. SURFACE HIGH PRESSURE NORTHEAST OF THE
AREA WILL KEEP EAST TO EAST SOUTHEAST TRADE WINDS BLOWING ACROSS THE
AREA SO SHOWERS WILL BE FOCUSED OVER WINDWARD AREAS. THE MOISTURE
WILL MOVE OFF TO THE WEST BY SUNDAY NIGHT AND WINDWARD SHOWERS WILL
DECREASE.

&&

.AVIATION...
STRONG TRADE WINDS WILL PRODUCE TEMP MOD TURB SOUTHWEST OF THE
ISLANDS BELOW 8000 FT AND AIRMET TANGO IS IN EFFECT FOR THIS
TURBULENCE. VFR CONDITIONS WILL PREVAIL...BUT ISOLATED MVFR
CONDITIONS ARE POSSIBLE...MAINLY OVER WINDWARD AREAS AND OVER
CENTRAL LANAI.

&&

.MARINE...
A SMALL CRAFT ADVISORY CONTINUES FOR THE WINDIER WATERS AROUND THE
BIG ISLAND AND MAUI COUNTY DUE TO STRONG EASTERLY TRADE WINDS. A
TROUGH MAY DROP THE WINDS BELOW THE ADVISORY LEVEL ON FRIDAY. WINDS
WILL LIKELY BE BACK UP TO ADVISORY LEVELS MAUI BY SATURDAY.

A LONG FETCH OF FRESH TO STRONG TRADE WINDS EAST OF THE ISLANDS WILL
BOOST SURF ALONG EAST FACING SHORES THROUGH EARLY NEXT WEEK AND A
SERIES OF SMALL NORTHWEST AND SOUTH SWELLS WILL CONTINUE...BUT SURF
IS EXPECTED TO REMAIN BELOW THE ADVISORY THRESHOLDS FOR THE NEXT
SEVERAL DAYS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 600 PM THURSDAY FOR MAALAEA BAY...THE
PAILOLO AND ALENUIHAHA CHANNELS AND WATERS SOUTH OF THE BIG ISLAND.

&&

$$
DONALDSON







000
FXHW60 PHFO 011336
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
330 AM HST WED APR 1 2015

.SYNOPSIS...
THE REMNANTS OF A LOW LEVEL TROUGH OVER THE W HALF OF THE ISLAND
CHAIN WILL CONTINUE TO GRADUALLY DISSIPATE TODAY. THE TRADES WILL
RETURN ACROSS THE AREA AND BECOME LOCALLY STRONG BY THIS
AFTERNOON...WITH SHOWERS FAVORING WINDWARD AND MOUNTAIN AREAS
THROUGH FRIDAY. ENHANCED MOISTURE SOUTHEAST OF THE STATE COULD BRING
INCREASING SHOWER ACTIVITY OVER THE BIG ISLAND DURING THE UPCOMING
WEEKEND.

&&

.DISCUSSION...
THE LINGERING CLOUDY SKIES AND SHOWERS ACROSS THE ISLANDS THIS
MORNING WILL CONTINUE TO GRADUALLY DECREASE AS AN UPPER LEVEL
SHORTWAVE TROUGH NE OF THE ALOHA STATE MOVES FURTHER AWAY FROM THE
AREA. ALSO..THE REMNANTS OF A LOW LEVEL TROUGH WILL GRADUALLY
DISSIPATE NEAR OAHU TODAY. THIS IS ALLOWING FOR SFC HIGH PRESSURE
CENTERED FAR NNE OF THE STATE TO RE-ESTABLISH AND BRING A MORE
ROBUST TRADE WIND PATTERN ACROSS THE ISLANDS...WITH SHOWERS AGAIN
FOCUSING OVER WINDWARD AND MAUKA AREAS. MODEL GUIDANCE IS ALSO
SHOWING SUBSIDENCE DEVELOPING ALOFT BEHIND THE DEPARTING SHORTWAVE
TROUGH...WHICH IS HELPING IN BRINGING A MORE STABLE AIRMASS ACROSS
THE AREA.

AT 315 AM HST...THE LATEST DATA FROM THE DOPPLER WEATHER RADAR
NETWORK WAS SHOWING MOST OF THE REMAINING SHOWERS ACROSS THE ISLANDS
LINGERING OVER THE KOOLAU RANGE IN OAHU...WINDWARD MAUI AND THE SE
SLOPES OF MAUNA LOA OVER THE BIG ISLAND. MEANWHILE...CLOUD MOTION ON
LATEST INFRARED SATELLITE IMAGERY SUGGEST THAT WINDS ACROSS THE
STATE ARE SHIFTING TO A MORE E FLOW...SIGNALING THE RETURN OF THE
TRADES. WIND SPEEDS WILL GRADUALLY STRENGTHEN THROUGH THE REST OF
THE MORNING HOURS...BECOMING RATHER ROBUST BY THIS AFTERNOON. THIS
TRADE WIND PATTERN WILL FURTHER SHIFT SHOWER ACTIVITY INTO WINDWARD
AND MOUNTAIN AREAS. ONLY EXCEPTION WILL BE THE LEEWARD BIG ISLAND
WHERE ONSHORE FLOW SHOULD BRING AFTERNOON CLOUD COVER AND A FEW
SHOWERS.

FOR THE REST OF THE WORK WEEK...THE TRADE WIND WEATHER REGIME IS
EXPECTED TO PREVAIL THROUGH FRI...A SOLUTION STILL SUPPORTED BY THE
ECMWF AND CANADIAN MODELS. GFS...ON THE OTHER HAND...REMAINS AS THE
OUTLIER BY BRINGING ANOTHER COLLAPSE OF THE TRADES STARTING LATE THU
AND INTO FRI...WITH A VERY MOIST AIRMASS FILTERING AT THE MID LEVELS
FROM SW AND S OF THE ISLANDS. THE REASON FOR THIS SYNOPTIC SCENARIO
IS AN APPROACHING MID/UPPER TROUGH FROM THE NW...WHICH GFS SEEMS TO
BE HAVING TROUBLE HANDLING ITS EVOLUTION AND EVENTUAL SOLUTION
DURING THE LATE THU TO FRI TIME FRAME. THIS RESULTS IN A
CONSIDERABLY MORE AGGRESSIVE RAIN EVENT FOR THE UPCOMING WEEKEND
COMPARED TO THE REST OF THE GUIDANCE. THUS...IT SEEMS REASONABLE TO
KEEP FOLLOWING THE ECMWF SOLUTION ATTM...WITH A LESS AGGRESSIVE
WEAKENING TREND OF THE TRADES ON FRI...AND WAIT FOR UPCOMING MODEL
GUIDANCE BEFORE MAKING ANY SIGNIFICANT ADJUSTMENTS TO THE ONGOING
FORECAST PHILOSOPHY.

FOR THE UPCOMING WEEKEND...IT IS LIKELY THAT ENHANCED MOISTURE SE OF
THE STATE WILL BRING INCREASING SHOWERS ACROSS THE BIG ISLAND LATE
SAT AND INTO SUN. TRADE WIND SHOWERS SHOULD CONTINUE EARLY NEXT WEEK
WITH MODEL GUIDANCE SHOWING STRONGER TRADES DEVELOPING ACROSS THE
AREA AS A STRENGTHENING HIGH PRESSURE SYSTEM REMAINS CENTERED FAR
NNE OF THE ALOHA STATE.

&&

.AVIATION...
REBUILDING TRADE WINDS AND INCREASED STABILITY ARE EXPECTED TODAY.
LIMITED MOISTURE WITHIN THE TRADE WIND FLOW WILL FOCUS SHRA ALONG
WINDWARD SLOPES AND COASTS...WHERE ISOL MVFR VIS/CIG CAN BE EXPECTED.
AIRMET TANGO FOR LOW LEVEL TURBULENCE TO THE W AND SW OF TERRAIN IS
LIKELY TO BE ISSUED. VFR WILL BE THE PREVAILING CONDITION AT THE
TERMINALS...ALTHOUGH PERIODS OF MVFR CIG ARE EXPECTED AT PHNY AROUND
MID-DAY...WITH BRIEF MVFR VIS/CIG IN SHRA POSSIBLE AT PHLI AND PHTO.

&&

.MARINE...
LATEST READINGS FROM THE ASCAT SCATTEROMETER PRODUCT SHOW WINDS IN
THE ALENUIHAHA CHANNEL ALREADY AT ADVISORY LEVELS. THUS...A SMALL
CRAFT ADVISORY HAS BEEN ISSUED FOR THE WINDIER WATERS AROUND THE
BIG ISLAND AND MAUI COUNTY. THE STRONG E WINDS SHOULD CONTINUE
THROUGH AT LEAST THURSDAY EVENING...AND THE ADVISORY COULD BE
EXTENDED BEYOND THURSDAY IF THE STRONG WINDS PERSIST.

A SMALL NORTHWEST SWELL WILL GRADUALLY DISSIPATE TODAY. A SMALL
SOUTH-SOUTHWEST SWELL IS EXPECTED TO ARRIVE DURING THE SECOND HALF
OF THE WORK WEEK.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST THURSDAY FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD













000
FXHW60 PHFO 011336
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
330 AM HST WED APR 1 2015

.SYNOPSIS...
THE REMNANTS OF A LOW LEVEL TROUGH OVER THE W HALF OF THE ISLAND
CHAIN WILL CONTINUE TO GRADUALLY DISSIPATE TODAY. THE TRADES WILL
RETURN ACROSS THE AREA AND BECOME LOCALLY STRONG BY THIS
AFTERNOON...WITH SHOWERS FAVORING WINDWARD AND MOUNTAIN AREAS
THROUGH FRIDAY. ENHANCED MOISTURE SOUTHEAST OF THE STATE COULD BRING
INCREASING SHOWER ACTIVITY OVER THE BIG ISLAND DURING THE UPCOMING
WEEKEND.

&&

.DISCUSSION...
THE LINGERING CLOUDY SKIES AND SHOWERS ACROSS THE ISLANDS THIS
MORNING WILL CONTINUE TO GRADUALLY DECREASE AS AN UPPER LEVEL
SHORTWAVE TROUGH NE OF THE ALOHA STATE MOVES FURTHER AWAY FROM THE
AREA. ALSO..THE REMNANTS OF A LOW LEVEL TROUGH WILL GRADUALLY
DISSIPATE NEAR OAHU TODAY. THIS IS ALLOWING FOR SFC HIGH PRESSURE
CENTERED FAR NNE OF THE STATE TO RE-ESTABLISH AND BRING A MORE
ROBUST TRADE WIND PATTERN ACROSS THE ISLANDS...WITH SHOWERS AGAIN
FOCUSING OVER WINDWARD AND MAUKA AREAS. MODEL GUIDANCE IS ALSO
SHOWING SUBSIDENCE DEVELOPING ALOFT BEHIND THE DEPARTING SHORTWAVE
TROUGH...WHICH IS HELPING IN BRINGING A MORE STABLE AIRMASS ACROSS
THE AREA.

AT 315 AM HST...THE LATEST DATA FROM THE DOPPLER WEATHER RADAR
NETWORK WAS SHOWING MOST OF THE REMAINING SHOWERS ACROSS THE ISLANDS
LINGERING OVER THE KOOLAU RANGE IN OAHU...WINDWARD MAUI AND THE SE
SLOPES OF MAUNA LOA OVER THE BIG ISLAND. MEANWHILE...CLOUD MOTION ON
LATEST INFRARED SATELLITE IMAGERY SUGGEST THAT WINDS ACROSS THE
STATE ARE SHIFTING TO A MORE E FLOW...SIGNALING THE RETURN OF THE
TRADES. WIND SPEEDS WILL GRADUALLY STRENGTHEN THROUGH THE REST OF
THE MORNING HOURS...BECOMING RATHER ROBUST BY THIS AFTERNOON. THIS
TRADE WIND PATTERN WILL FURTHER SHIFT SHOWER ACTIVITY INTO WINDWARD
AND MOUNTAIN AREAS. ONLY EXCEPTION WILL BE THE LEEWARD BIG ISLAND
WHERE ONSHORE FLOW SHOULD BRING AFTERNOON CLOUD COVER AND A FEW
SHOWERS.

FOR THE REST OF THE WORK WEEK...THE TRADE WIND WEATHER REGIME IS
EXPECTED TO PREVAIL THROUGH FRI...A SOLUTION STILL SUPPORTED BY THE
ECMWF AND CANADIAN MODELS. GFS...ON THE OTHER HAND...REMAINS AS THE
OUTLIER BY BRINGING ANOTHER COLLAPSE OF THE TRADES STARTING LATE THU
AND INTO FRI...WITH A VERY MOIST AIRMASS FILTERING AT THE MID LEVELS
FROM SW AND S OF THE ISLANDS. THE REASON FOR THIS SYNOPTIC SCENARIO
IS AN APPROACHING MID/UPPER TROUGH FROM THE NW...WHICH GFS SEEMS TO
BE HAVING TROUBLE HANDLING ITS EVOLUTION AND EVENTUAL SOLUTION
DURING THE LATE THU TO FRI TIME FRAME. THIS RESULTS IN A
CONSIDERABLY MORE AGGRESSIVE RAIN EVENT FOR THE UPCOMING WEEKEND
COMPARED TO THE REST OF THE GUIDANCE. THUS...IT SEEMS REASONABLE TO
KEEP FOLLOWING THE ECMWF SOLUTION ATTM...WITH A LESS AGGRESSIVE
WEAKENING TREND OF THE TRADES ON FRI...AND WAIT FOR UPCOMING MODEL
GUIDANCE BEFORE MAKING ANY SIGNIFICANT ADJUSTMENTS TO THE ONGOING
FORECAST PHILOSOPHY.

FOR THE UPCOMING WEEKEND...IT IS LIKELY THAT ENHANCED MOISTURE SE OF
THE STATE WILL BRING INCREASING SHOWERS ACROSS THE BIG ISLAND LATE
SAT AND INTO SUN. TRADE WIND SHOWERS SHOULD CONTINUE EARLY NEXT WEEK
WITH MODEL GUIDANCE SHOWING STRONGER TRADES DEVELOPING ACROSS THE
AREA AS A STRENGTHENING HIGH PRESSURE SYSTEM REMAINS CENTERED FAR
NNE OF THE ALOHA STATE.

&&

.AVIATION...
REBUILDING TRADE WINDS AND INCREASED STABILITY ARE EXPECTED TODAY.
LIMITED MOISTURE WITHIN THE TRADE WIND FLOW WILL FOCUS SHRA ALONG
WINDWARD SLOPES AND COASTS...WHERE ISOL MVFR VIS/CIG CAN BE EXPECTED.
AIRMET TANGO FOR LOW LEVEL TURBULENCE TO THE W AND SW OF TERRAIN IS
LIKELY TO BE ISSUED. VFR WILL BE THE PREVAILING CONDITION AT THE
TERMINALS...ALTHOUGH PERIODS OF MVFR CIG ARE EXPECTED AT PHNY AROUND
MID-DAY...WITH BRIEF MVFR VIS/CIG IN SHRA POSSIBLE AT PHLI AND PHTO.

&&

.MARINE...
LATEST READINGS FROM THE ASCAT SCATTEROMETER PRODUCT SHOW WINDS IN
THE ALENUIHAHA CHANNEL ALREADY AT ADVISORY LEVELS. THUS...A SMALL
CRAFT ADVISORY HAS BEEN ISSUED FOR THE WINDIER WATERS AROUND THE
BIG ISLAND AND MAUI COUNTY. THE STRONG E WINDS SHOULD CONTINUE
THROUGH AT LEAST THURSDAY EVENING...AND THE ADVISORY COULD BE
EXTENDED BEYOND THURSDAY IF THE STRONG WINDS PERSIST.

A SMALL NORTHWEST SWELL WILL GRADUALLY DISSIPATE TODAY. A SMALL
SOUTH-SOUTHWEST SWELL IS EXPECTED TO ARRIVE DURING THE SECOND HALF
OF THE WORK WEEK.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST THURSDAY FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD














000
FXHW60 PHFO 010630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH OVER THE W HALF OF THE ISLAND CHAIN WILL
GRADUALLY DISSIPATE TONIGHT. THE TRADES WILL RETURN ON WEDNESDAY
AND BECOME LOCALLY STRONG...WITH SHOWERS FAVORING WINDWARD AND
MOUNTAIN AREAS THROUGH FRIDAY. ENHANCED MOISTURE SOUTHEAST OF THE
STATE COULD BRING INCREASING SHOWER ACTIVITY OVER THE BIG ISLAND
DURING THE UPCOMING WEEKEND.

&&

.DISCUSSION...
THE CLOUDY SKIES AND LINGERING SHOWERS ACROSS OAHU WILL CONTINUE TO
DECREASE THROUGH THE REST OF THE EVENING HOURS AS AN UPPER LEVEL
SHORTWAVE TROUGH PUSHES FURTHER TO THE NE OF THE ALOHA STATE...AND
ITS ASSOCIATED DISSIPATING LOW LVL TROUGH MOVES DOWN TO THE KAUAI
CHANNEL OR MAYBE OAHU TONIGHT. THIS TROUGH IS HARDLY RECOGNIZABLE
ON SATELLITE AND RADAR DATA...AND SHOULD NOT BRING ANY MORE
SIGNIFICANT IMPACTS WEATHERWISE ACROSS THE AREA THROUGH THE REST OF
THIS EVENING. MODELS SHOW SUBSIDENCE ALOFT BEHIND THE DEPARTING
SHORTWAVE TROUGH...WHICH WILL HELP IN BRINGING A MORE STABLE AIRMASS
ACROSS THE AREA.

AT 8 PM HST...RADAR AND IR SATELLITE DATA SHOWED CLOUD COVERAGE OVER
KAUAI GRADUALLY CLEARING OUT WITH ONLY LOCALIZED PATCHES OF LOW
CLOUDS LINGERING OVER INTERIOR AREAS. ON MAUI COUNTY...SHOWERS
LINGER OVER LEEWARD AREAS...BUT WITH ACCUMULATIONS REMAINING LIGHT.
SOME LINGERING SHOWERS CAN ALSO BE OBSERVED OVER THE SE SLOPES OF
MAUNA LOA IN THE BIG ISLAND...WITH THE AFTERNOON CLOUD BUILD-UPS
NOW SLOWLY DISSIPATING.

CLOUD MOTION ON EARLIER VISIBLE AND CURRENT INFRARED SATELLITE
IMAGERY SUGGEST THAT WINDS ACROSS THE STATE ARE STARTING TO SHIFT TO
A MORE E FLOW...WHICH WILL GRADUALLY STRENGTHEN FROM LATER TONIGHT
THROUGH WED MORNING. BY WED AFTERNOON...A RATHER ROBUST TRADE WIND
PATTERN SHOULD ESTABLISH WITH NO SEA BREEZES EXPECTED AND SHOWER
ACTIVITY SHIFTING TO WINDWARD AND MOUNTAIN AREAS. ONLY EXCEPTION
WILL BE THE LEEWARD BIG ISLAND WHERE ONSHORE FLOW SHOULD BRING
AFTERNOON CLOUD COVER AND A FEW SHOWERS. THE RETURNING TRADES WILL
BE SUPPORTED BY A BROAD SFC HIGH PRESSURE SYSTEM FAR NNE OF THE
ISLAND CHAIN REGAINING STRENGTH IN THE WAKE OF THE UPPER SHORTWAVE
TROUGH.

THE FORECAST PHILOSOPHY FOR THE REST OF THE WORK WEEK REMAINS
UNCHANGED WITH A TRADE WIND WEATHER REGIME EXPECTED TO PREVAIL
THROUGH FRI. THIS SOLUTION IS STILL SUPPORTED BY ECMWF AND CANADIAN
MODELS. GFS...ON THE OTHER HAND...REMAINS AS THE OUTLIER BY
BRINGING ANOTHER COLLAPSE OF THE TRADES STARTING LATE THU AND INTO
FRI...WHILE BRINGING A VERY MOIST AIRMASS AT THE MID LEVELS FROM THE
SE AND S OF THE ISLANDS. BUT IT SEEMS THAT GFS IS NOT HANDLING WELL
THE EVOLUTION AND EVENTUAL SOLUTION OF A MID/UPPER TROUGH
APPROACHING KAUAI FROM THE NW IN THAT SAME TIME FRAME...BRINGING A
MUCH MORE AGGRESSIVE RAIN EVENT FOR THE UPCOMING WEEKEND. THUS...IT
SEEMS REASONABLE TO KEEP FOLLOWING THE ECMWF SOLUTION...WITH PERHAPS
A LESS AGGRESSIVE WEAKENING TREND OF THE TRADES ON FRI...AND WAIT
FOR UPCOMING MODEL GUIDANCE BEFORE MAKING ANY SIGNIFICANT
ADJUSTMENTS TO THE FORECAST PHILOSOPHY FOR THE WEEKEND. BUT
REGARDLESS OF THE FINAL OUTCOME...IT IS LIKELY THAT ENHANCED
MOISTURE SE OF THE STATE WILL BRING INCREASING SHOWERS ACROSS THE
BIG ISLAND SAT AND SUN.

&&

.AVIATION...
THE TREND THROUGH WEDNESDAY IS FOR GRADUALLY REBUILDING TRADE WINDS
AND AN INCREASINGLY STABLE ISLAND ATMOSPHERE. VFR CONDITIONS WILL
PREVAIL THROUGH THE PERIOD...WITH OVERNIGHT LAND BREEZES ACTING TO
CLEAR MOST LEEWARD AREAS. THE RETURNING TRADE WINDS WILL FOCUS
LIMITED MOISTURE ALONG WINDWARD SLOPES AND COASTS...WHERE ISOL MVFR
VIS/CIG IN SHRA CAN BE EXPECTED.

&&

.MARINE...
WINDS WILL REMAIN BELOW ADVISORY CRITERIA THROUGH WED MORNING...THEN
SPEEDS WILL INCREASE AND LIKELY REACHING ADVISORY LEVELS BY
WEDNESDAY AFTERNOON OVER THE TYPICALLY WINDIER WATERS AROUND THE BIG
ISLAND AND MAUI COUNTY.

THE CURRENT SMALL NORTHWEST SWELL WILL DISSIPATE BY WEDNESDAY. A
SMALL SOUTH-SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER
THE NEXT COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL
FOR THE SECOND HALF OF THE WORK WEEK.

&&

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

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD












000
FXHW60 PHFO 010630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH OVER THE W HALF OF THE ISLAND CHAIN WILL
GRADUALLY DISSIPATE TONIGHT. THE TRADES WILL RETURN ON WEDNESDAY
AND BECOME LOCALLY STRONG...WITH SHOWERS FAVORING WINDWARD AND
MOUNTAIN AREAS THROUGH FRIDAY. ENHANCED MOISTURE SOUTHEAST OF THE
STATE COULD BRING INCREASING SHOWER ACTIVITY OVER THE BIG ISLAND
DURING THE UPCOMING WEEKEND.

&&

.DISCUSSION...
THE CLOUDY SKIES AND LINGERING SHOWERS ACROSS OAHU WILL CONTINUE TO
DECREASE THROUGH THE REST OF THE EVENING HOURS AS AN UPPER LEVEL
SHORTWAVE TROUGH PUSHES FURTHER TO THE NE OF THE ALOHA STATE...AND
ITS ASSOCIATED DISSIPATING LOW LVL TROUGH MOVES DOWN TO THE KAUAI
CHANNEL OR MAYBE OAHU TONIGHT. THIS TROUGH IS HARDLY RECOGNIZABLE
ON SATELLITE AND RADAR DATA...AND SHOULD NOT BRING ANY MORE
SIGNIFICANT IMPACTS WEATHERWISE ACROSS THE AREA THROUGH THE REST OF
THIS EVENING. MODELS SHOW SUBSIDENCE ALOFT BEHIND THE DEPARTING
SHORTWAVE TROUGH...WHICH WILL HELP IN BRINGING A MORE STABLE AIRMASS
ACROSS THE AREA.

AT 8 PM HST...RADAR AND IR SATELLITE DATA SHOWED CLOUD COVERAGE OVER
KAUAI GRADUALLY CLEARING OUT WITH ONLY LOCALIZED PATCHES OF LOW
CLOUDS LINGERING OVER INTERIOR AREAS. ON MAUI COUNTY...SHOWERS
LINGER OVER LEEWARD AREAS...BUT WITH ACCUMULATIONS REMAINING LIGHT.
SOME LINGERING SHOWERS CAN ALSO BE OBSERVED OVER THE SE SLOPES OF
MAUNA LOA IN THE BIG ISLAND...WITH THE AFTERNOON CLOUD BUILD-UPS
NOW SLOWLY DISSIPATING.

CLOUD MOTION ON EARLIER VISIBLE AND CURRENT INFRARED SATELLITE
IMAGERY SUGGEST THAT WINDS ACROSS THE STATE ARE STARTING TO SHIFT TO
A MORE E FLOW...WHICH WILL GRADUALLY STRENGTHEN FROM LATER TONIGHT
THROUGH WED MORNING. BY WED AFTERNOON...A RATHER ROBUST TRADE WIND
PATTERN SHOULD ESTABLISH WITH NO SEA BREEZES EXPECTED AND SHOWER
ACTIVITY SHIFTING TO WINDWARD AND MOUNTAIN AREAS. ONLY EXCEPTION
WILL BE THE LEEWARD BIG ISLAND WHERE ONSHORE FLOW SHOULD BRING
AFTERNOON CLOUD COVER AND A FEW SHOWERS. THE RETURNING TRADES WILL
BE SUPPORTED BY A BROAD SFC HIGH PRESSURE SYSTEM FAR NNE OF THE
ISLAND CHAIN REGAINING STRENGTH IN THE WAKE OF THE UPPER SHORTWAVE
TROUGH.

THE FORECAST PHILOSOPHY FOR THE REST OF THE WORK WEEK REMAINS
UNCHANGED WITH A TRADE WIND WEATHER REGIME EXPECTED TO PREVAIL
THROUGH FRI. THIS SOLUTION IS STILL SUPPORTED BY ECMWF AND CANADIAN
MODELS. GFS...ON THE OTHER HAND...REMAINS AS THE OUTLIER BY
BRINGING ANOTHER COLLAPSE OF THE TRADES STARTING LATE THU AND INTO
FRI...WHILE BRINGING A VERY MOIST AIRMASS AT THE MID LEVELS FROM THE
SE AND S OF THE ISLANDS. BUT IT SEEMS THAT GFS IS NOT HANDLING WELL
THE EVOLUTION AND EVENTUAL SOLUTION OF A MID/UPPER TROUGH
APPROACHING KAUAI FROM THE NW IN THAT SAME TIME FRAME...BRINGING A
MUCH MORE AGGRESSIVE RAIN EVENT FOR THE UPCOMING WEEKEND. THUS...IT
SEEMS REASONABLE TO KEEP FOLLOWING THE ECMWF SOLUTION...WITH PERHAPS
A LESS AGGRESSIVE WEAKENING TREND OF THE TRADES ON FRI...AND WAIT
FOR UPCOMING MODEL GUIDANCE BEFORE MAKING ANY SIGNIFICANT
ADJUSTMENTS TO THE FORECAST PHILOSOPHY FOR THE WEEKEND. BUT
REGARDLESS OF THE FINAL OUTCOME...IT IS LIKELY THAT ENHANCED
MOISTURE SE OF THE STATE WILL BRING INCREASING SHOWERS ACROSS THE
BIG ISLAND SAT AND SUN.

&&

.AVIATION...
THE TREND THROUGH WEDNESDAY IS FOR GRADUALLY REBUILDING TRADE WINDS
AND AN INCREASINGLY STABLE ISLAND ATMOSPHERE. VFR CONDITIONS WILL
PREVAIL THROUGH THE PERIOD...WITH OVERNIGHT LAND BREEZES ACTING TO
CLEAR MOST LEEWARD AREAS. THE RETURNING TRADE WINDS WILL FOCUS
LIMITED MOISTURE ALONG WINDWARD SLOPES AND COASTS...WHERE ISOL MVFR
VIS/CIG IN SHRA CAN BE EXPECTED.

&&

.MARINE...
WINDS WILL REMAIN BELOW ADVISORY CRITERIA THROUGH WED MORNING...THEN
SPEEDS WILL INCREASE AND LIKELY REACHING ADVISORY LEVELS BY
WEDNESDAY AFTERNOON OVER THE TYPICALLY WINDIER WATERS AROUND THE BIG
ISLAND AND MAUI COUNTY.

THE CURRENT SMALL NORTHWEST SWELL WILL DISSIPATE BY WEDNESDAY. A
SMALL SOUTH-SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER
THE NEXT COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL
FOR THE SECOND HALF OF THE WORK WEEK.

&&

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

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD












000
FXHW60 PHFO 010630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH OVER THE W HALF OF THE ISLAND CHAIN WILL
GRADUALLY DISSIPATE TONIGHT. THE TRADES WILL RETURN ON WEDNESDAY
AND BECOME LOCALLY STRONG...WITH SHOWERS FAVORING WINDWARD AND
MOUNTAIN AREAS THROUGH FRIDAY. ENHANCED MOISTURE SOUTHEAST OF THE
STATE COULD BRING INCREASING SHOWER ACTIVITY OVER THE BIG ISLAND
DURING THE UPCOMING WEEKEND.

&&

.DISCUSSION...
THE CLOUDY SKIES AND LINGERING SHOWERS ACROSS OAHU WILL CONTINUE TO
DECREASE THROUGH THE REST OF THE EVENING HOURS AS AN UPPER LEVEL
SHORTWAVE TROUGH PUSHES FURTHER TO THE NE OF THE ALOHA STATE...AND
ITS ASSOCIATED DISSIPATING LOW LVL TROUGH MOVES DOWN TO THE KAUAI
CHANNEL OR MAYBE OAHU TONIGHT. THIS TROUGH IS HARDLY RECOGNIZABLE
ON SATELLITE AND RADAR DATA...AND SHOULD NOT BRING ANY MORE
SIGNIFICANT IMPACTS WEATHERWISE ACROSS THE AREA THROUGH THE REST OF
THIS EVENING. MODELS SHOW SUBSIDENCE ALOFT BEHIND THE DEPARTING
SHORTWAVE TROUGH...WHICH WILL HELP IN BRINGING A MORE STABLE AIRMASS
ACROSS THE AREA.

AT 8 PM HST...RADAR AND IR SATELLITE DATA SHOWED CLOUD COVERAGE OVER
KAUAI GRADUALLY CLEARING OUT WITH ONLY LOCALIZED PATCHES OF LOW
CLOUDS LINGERING OVER INTERIOR AREAS. ON MAUI COUNTY...SHOWERS
LINGER OVER LEEWARD AREAS...BUT WITH ACCUMULATIONS REMAINING LIGHT.
SOME LINGERING SHOWERS CAN ALSO BE OBSERVED OVER THE SE SLOPES OF
MAUNA LOA IN THE BIG ISLAND...WITH THE AFTERNOON CLOUD BUILD-UPS
NOW SLOWLY DISSIPATING.

CLOUD MOTION ON EARLIER VISIBLE AND CURRENT INFRARED SATELLITE
IMAGERY SUGGEST THAT WINDS ACROSS THE STATE ARE STARTING TO SHIFT TO
A MORE E FLOW...WHICH WILL GRADUALLY STRENGTHEN FROM LATER TONIGHT
THROUGH WED MORNING. BY WED AFTERNOON...A RATHER ROBUST TRADE WIND
PATTERN SHOULD ESTABLISH WITH NO SEA BREEZES EXPECTED AND SHOWER
ACTIVITY SHIFTING TO WINDWARD AND MOUNTAIN AREAS. ONLY EXCEPTION
WILL BE THE LEEWARD BIG ISLAND WHERE ONSHORE FLOW SHOULD BRING
AFTERNOON CLOUD COVER AND A FEW SHOWERS. THE RETURNING TRADES WILL
BE SUPPORTED BY A BROAD SFC HIGH PRESSURE SYSTEM FAR NNE OF THE
ISLAND CHAIN REGAINING STRENGTH IN THE WAKE OF THE UPPER SHORTWAVE
TROUGH.

THE FORECAST PHILOSOPHY FOR THE REST OF THE WORK WEEK REMAINS
UNCHANGED WITH A TRADE WIND WEATHER REGIME EXPECTED TO PREVAIL
THROUGH FRI. THIS SOLUTION IS STILL SUPPORTED BY ECMWF AND CANADIAN
MODELS. GFS...ON THE OTHER HAND...REMAINS AS THE OUTLIER BY
BRINGING ANOTHER COLLAPSE OF THE TRADES STARTING LATE THU AND INTO
FRI...WHILE BRINGING A VERY MOIST AIRMASS AT THE MID LEVELS FROM THE
SE AND S OF THE ISLANDS. BUT IT SEEMS THAT GFS IS NOT HANDLING WELL
THE EVOLUTION AND EVENTUAL SOLUTION OF A MID/UPPER TROUGH
APPROACHING KAUAI FROM THE NW IN THAT SAME TIME FRAME...BRINGING A
MUCH MORE AGGRESSIVE RAIN EVENT FOR THE UPCOMING WEEKEND. THUS...IT
SEEMS REASONABLE TO KEEP FOLLOWING THE ECMWF SOLUTION...WITH PERHAPS
A LESS AGGRESSIVE WEAKENING TREND OF THE TRADES ON FRI...AND WAIT
FOR UPCOMING MODEL GUIDANCE BEFORE MAKING ANY SIGNIFICANT
ADJUSTMENTS TO THE FORECAST PHILOSOPHY FOR THE WEEKEND. BUT
REGARDLESS OF THE FINAL OUTCOME...IT IS LIKELY THAT ENHANCED
MOISTURE SE OF THE STATE WILL BRING INCREASING SHOWERS ACROSS THE
BIG ISLAND SAT AND SUN.

&&

.AVIATION...
THE TREND THROUGH WEDNESDAY IS FOR GRADUALLY REBUILDING TRADE WINDS
AND AN INCREASINGLY STABLE ISLAND ATMOSPHERE. VFR CONDITIONS WILL
PREVAIL THROUGH THE PERIOD...WITH OVERNIGHT LAND BREEZES ACTING TO
CLEAR MOST LEEWARD AREAS. THE RETURNING TRADE WINDS WILL FOCUS
LIMITED MOISTURE ALONG WINDWARD SLOPES AND COASTS...WHERE ISOL MVFR
VIS/CIG IN SHRA CAN BE EXPECTED.

&&

.MARINE...
WINDS WILL REMAIN BELOW ADVISORY CRITERIA THROUGH WED MORNING...THEN
SPEEDS WILL INCREASE AND LIKELY REACHING ADVISORY LEVELS BY
WEDNESDAY AFTERNOON OVER THE TYPICALLY WINDIER WATERS AROUND THE BIG
ISLAND AND MAUI COUNTY.

THE CURRENT SMALL NORTHWEST SWELL WILL DISSIPATE BY WEDNESDAY. A
SMALL SOUTH-SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER
THE NEXT COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL
FOR THE SECOND HALF OF THE WORK WEEK.

&&

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

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD











000
FXHW60 PHFO 010630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH OVER THE W HALF OF THE ISLAND CHAIN WILL
GRADUALLY DISSIPATE TONIGHT. THE TRADES WILL RETURN ON WEDNESDAY
AND BECOME LOCALLY STRONG...WITH SHOWERS FAVORING WINDWARD AND
MOUNTAIN AREAS THROUGH FRIDAY. ENHANCED MOISTURE SOUTHEAST OF THE
STATE COULD BRING INCREASING SHOWER ACTIVITY OVER THE BIG ISLAND
DURING THE UPCOMING WEEKEND.

&&

.DISCUSSION...
THE CLOUDY SKIES AND LINGERING SHOWERS ACROSS OAHU WILL CONTINUE TO
DECREASE THROUGH THE REST OF THE EVENING HOURS AS AN UPPER LEVEL
SHORTWAVE TROUGH PUSHES FURTHER TO THE NE OF THE ALOHA STATE...AND
ITS ASSOCIATED DISSIPATING LOW LVL TROUGH MOVES DOWN TO THE KAUAI
CHANNEL OR MAYBE OAHU TONIGHT. THIS TROUGH IS HARDLY RECOGNIZABLE
ON SATELLITE AND RADAR DATA...AND SHOULD NOT BRING ANY MORE
SIGNIFICANT IMPACTS WEATHERWISE ACROSS THE AREA THROUGH THE REST OF
THIS EVENING. MODELS SHOW SUBSIDENCE ALOFT BEHIND THE DEPARTING
SHORTWAVE TROUGH...WHICH WILL HELP IN BRINGING A MORE STABLE AIRMASS
ACROSS THE AREA.

AT 8 PM HST...RADAR AND IR SATELLITE DATA SHOWED CLOUD COVERAGE OVER
KAUAI GRADUALLY CLEARING OUT WITH ONLY LOCALIZED PATCHES OF LOW
CLOUDS LINGERING OVER INTERIOR AREAS. ON MAUI COUNTY...SHOWERS
LINGER OVER LEEWARD AREAS...BUT WITH ACCUMULATIONS REMAINING LIGHT.
SOME LINGERING SHOWERS CAN ALSO BE OBSERVED OVER THE SE SLOPES OF
MAUNA LOA IN THE BIG ISLAND...WITH THE AFTERNOON CLOUD BUILD-UPS
NOW SLOWLY DISSIPATING.

CLOUD MOTION ON EARLIER VISIBLE AND CURRENT INFRARED SATELLITE
IMAGERY SUGGEST THAT WINDS ACROSS THE STATE ARE STARTING TO SHIFT TO
A MORE E FLOW...WHICH WILL GRADUALLY STRENGTHEN FROM LATER TONIGHT
THROUGH WED MORNING. BY WED AFTERNOON...A RATHER ROBUST TRADE WIND
PATTERN SHOULD ESTABLISH WITH NO SEA BREEZES EXPECTED AND SHOWER
ACTIVITY SHIFTING TO WINDWARD AND MOUNTAIN AREAS. ONLY EXCEPTION
WILL BE THE LEEWARD BIG ISLAND WHERE ONSHORE FLOW SHOULD BRING
AFTERNOON CLOUD COVER AND A FEW SHOWERS. THE RETURNING TRADES WILL
BE SUPPORTED BY A BROAD SFC HIGH PRESSURE SYSTEM FAR NNE OF THE
ISLAND CHAIN REGAINING STRENGTH IN THE WAKE OF THE UPPER SHORTWAVE
TROUGH.

THE FORECAST PHILOSOPHY FOR THE REST OF THE WORK WEEK REMAINS
UNCHANGED WITH A TRADE WIND WEATHER REGIME EXPECTED TO PREVAIL
THROUGH FRI. THIS SOLUTION IS STILL SUPPORTED BY ECMWF AND CANADIAN
MODELS. GFS...ON THE OTHER HAND...REMAINS AS THE OUTLIER BY
BRINGING ANOTHER COLLAPSE OF THE TRADES STARTING LATE THU AND INTO
FRI...WHILE BRINGING A VERY MOIST AIRMASS AT THE MID LEVELS FROM THE
SE AND S OF THE ISLANDS. BUT IT SEEMS THAT GFS IS NOT HANDLING WELL
THE EVOLUTION AND EVENTUAL SOLUTION OF A MID/UPPER TROUGH
APPROACHING KAUAI FROM THE NW IN THAT SAME TIME FRAME...BRINGING A
MUCH MORE AGGRESSIVE RAIN EVENT FOR THE UPCOMING WEEKEND. THUS...IT
SEEMS REASONABLE TO KEEP FOLLOWING THE ECMWF SOLUTION...WITH PERHAPS
A LESS AGGRESSIVE WEAKENING TREND OF THE TRADES ON FRI...AND WAIT
FOR UPCOMING MODEL GUIDANCE BEFORE MAKING ANY SIGNIFICANT
ADJUSTMENTS TO THE FORECAST PHILOSOPHY FOR THE WEEKEND. BUT
REGARDLESS OF THE FINAL OUTCOME...IT IS LIKELY THAT ENHANCED
MOISTURE SE OF THE STATE WILL BRING INCREASING SHOWERS ACROSS THE
BIG ISLAND SAT AND SUN.

&&

.AVIATION...
THE TREND THROUGH WEDNESDAY IS FOR GRADUALLY REBUILDING TRADE WINDS
AND AN INCREASINGLY STABLE ISLAND ATMOSPHERE. VFR CONDITIONS WILL
PREVAIL THROUGH THE PERIOD...WITH OVERNIGHT LAND BREEZES ACTING TO
CLEAR MOST LEEWARD AREAS. THE RETURNING TRADE WINDS WILL FOCUS
LIMITED MOISTURE ALONG WINDWARD SLOPES AND COASTS...WHERE ISOL MVFR
VIS/CIG IN SHRA CAN BE EXPECTED.

&&

.MARINE...
WINDS WILL REMAIN BELOW ADVISORY CRITERIA THROUGH WED MORNING...THEN
SPEEDS WILL INCREASE AND LIKELY REACHING ADVISORY LEVELS BY
WEDNESDAY AFTERNOON OVER THE TYPICALLY WINDIER WATERS AROUND THE BIG
ISLAND AND MAUI COUNTY.

THE CURRENT SMALL NORTHWEST SWELL WILL DISSIPATE BY WEDNESDAY. A
SMALL SOUTH-SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER
THE NEXT COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL
FOR THE SECOND HALF OF THE WORK WEEK.

&&

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

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD











000
FXHW60 PHFO 010155
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
330 PM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH NEAR KAUAI IS EXPECTED TO DISSIPATE OVER THE
WESTERN ISLANDS THIS EVENING. THIS WILL ALLOW LOCALLY STRONG TRADES
TO RETURN TO ALL AREAS WEDNESDAY. TRADE WIND CONDITIONS WILL PERSIST
INTO THE WEEKEND WITH SHOWERS FAVORING THE WINDWARD AND MOUNTAIN
AREAS.

&&

.DISCUSSION...
AS OF 3 PM HST...THE AFTERNOON CONVECTION ON KAUAI HAS BE SPOTTY AT
BEST AND CONFINED TO MAINLY THE SOUTHERN HALF OF THE ISLAND. THE
NORTHERN HALF IS PARTLY SUNNY AND MAINLY DRY. ON OAHU...IT HAS BEEN
SPOTTY AS WELL...FAVORING THE WAIANAE AND KOOLAU MOUNTAINS AND
WINDWARD COAST. LANAI HAD A HEAVY SHOWER OR TWO A SHORT TIME AGO
WHILE MOLOKAI AND MAUI HAVE BEEN GENERALLY QUIET...MAY BE A BRIEF
SHOWER OR TWO AT BEST. IN SHORT...SHOWER ACTIVITY IS SOMEWHAT LESS
THAN EXPECTED.

OTHER NOTEWORTHY OBSERVATIONS AS OF 230 PM HST...WIND DATA STATEWIDE
SHOWS THE EXTENT OF THE LIGHT AND VARIABLE WINDS AFFECTING MORE
ISLANDS THAN EXPECTED...REACHING OUT TO MOLOKAI AND WEST MAUI.
ALSO...THE AFTERNOON CLOUDS HAVE REACHED THE TWO SUMMITS ON THE BIG
ISLAND INCLUDING A BRIEF SHOWERS ON THE NORTHWEST SIDE OF MAUNA LOA.
SO ADJUSTMENTS HAVE BEEN MADE TO THESE AREAS. INCLUDING A SLIGHT
CHANCE FOR A SHOWER FOR THE SUMMITS FOR THE REST OF THIS AFTERNOON.

ALTHOUGH DIFFICULT TO PIN POINT BUT WE ARE PLACING THE LOW
LEVEL TROUGH OVER KAUAI THIS AFTERNOON AS PER GFS SOLUTION. IT IS
FORECAST TO EASE INTO THE KAUAI CHANNEL SHORTLY AND DISSIPATE THERE
EARLY THIS EVENING.

WATER VAPOR IMAGERY SHOWS THUNDERSTORMS CONTINUING OVER THE OFFSHORE
WATERS NORTH OF MOLOKAI AND MAUI. AN UPPER LEVEL SHORT WAVE TROUGH
IS THE RESPONSIBLE FEATURE FOR THESE STORMS. THE TROUGH IS MOVING
EAST AT 25 MPH...AND AT THIS RATE...PUTS THE UPPER TROUGH JUST EAST
OF THE BIG ISLAND AT 8 PM HST THIS EVENING. SO WITH THE UPPER TROUGH
LIFTING OUT...THE LOW LEVEL TROUGH FILLING...THE LOSS OF DAYTIME
HEATING...AND THE LACK OF SHOWERS...WE ANTICIPATE ANY REMAINING
SHOWERS TO END SHORTLY AFTER THE SUN SETS. IT IS A PRETTY DRY
EASTERLY WIND FLOW EAST OF MOLOKAI AS WELL. SO EXPECT A MAIN DRY
NIGHT ALL AREAS TONIGHT. ANY TRADE SHOWERS WILL LIKELY COME WELL
AFTER MIDNIGHT. EXPECT MORE TRADE SHOWERS FROM WEDNESDAY NIGHT ON.
THE REST OF THE FORECAST REMAINS INTACT WITH STRENGTHENING TRADES
REACHING LOCALLY STRONG OVER THE WATERS AROUND MAUI AND SOUTH OF THE
BIG ISLAND BY WEDNESDAY AFTERNOON. THE TRADES ARE EXPECTED TO SLIP
TO MODERATE SPEEDS FROM FRIDAY ON.

THERE REMAINS SOME DISCREPANCY BETWEEN THE EC AND GFS THURSDAY NIGHT
THROUGH SATURDAY WITH THE GFS BRINGING LIGHTER WINDS OVERALL AND
INCREASED MOISTURE TO THE BIG ISLAND. WE ARE CURRENTLY RIDING THE EC
SOLUTION AND CLIMATOLOGY WITH CONTINUED MODERATE TRADES INTO THE
WEEKEND.

&&

.AVIATION...
AIRMET SIERRA IS IN PLACE FOR ALL OF THE ISLANDS BUT SHOULD BE
LIFTED SOMETIME EARLY THIS EVENING. IT SHOULD BE A RELATIVELY
AIRMET-FREE NIGHT OTHERWISE.

&&

.MARINE...
WINDS WILL REMAIN BELOW SMALL CRAFT ADVISORY /SCA/ SPEEDS THROUGH
TONIGHT. TRADES ARE EXPECTED TO RETURN TO KAUAI AND OAHU BY DAYBREAK
WEDNESDAY AS THE TROUGH NEAR KAUAI AND OAHU DISSIPATES THIS EVENING.
THE TRADES WILL CONTINUE TO STRENGTHEN INTO WEDNESDAY REACHING
LOCALLY STRONG SPEEDS BY THE AFTERNOON...AND A SCA...FOR WATERS
AROUND MAUI AND SOUTH OF THE BIG ISLAND.

THE CURRENT SMALL NORTHWEST SWELL WILL DISSIPATE BY WEDNESDAY. A
SMALL SOUTH-SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER
THE NEXT COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL
FOR THE SECOND HALF OF THE WORK WEEK.

&&

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

&&

$$

DISCUSSION...LAU










000
FXHW60 PHFO 010155
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
330 PM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH NEAR KAUAI IS EXPECTED TO DISSIPATE OVER THE
WESTERN ISLANDS THIS EVENING. THIS WILL ALLOW LOCALLY STRONG TRADES
TO RETURN TO ALL AREAS WEDNESDAY. TRADE WIND CONDITIONS WILL PERSIST
INTO THE WEEKEND WITH SHOWERS FAVORING THE WINDWARD AND MOUNTAIN
AREAS.

&&

.DISCUSSION...
AS OF 3 PM HST...THE AFTERNOON CONVECTION ON KAUAI HAS BE SPOTTY AT
BEST AND CONFINED TO MAINLY THE SOUTHERN HALF OF THE ISLAND. THE
NORTHERN HALF IS PARTLY SUNNY AND MAINLY DRY. ON OAHU...IT HAS BEEN
SPOTTY AS WELL...FAVORING THE WAIANAE AND KOOLAU MOUNTAINS AND
WINDWARD COAST. LANAI HAD A HEAVY SHOWER OR TWO A SHORT TIME AGO
WHILE MOLOKAI AND MAUI HAVE BEEN GENERALLY QUIET...MAY BE A BRIEF
SHOWER OR TWO AT BEST. IN SHORT...SHOWER ACTIVITY IS SOMEWHAT LESS
THAN EXPECTED.

OTHER NOTEWORTHY OBSERVATIONS AS OF 230 PM HST...WIND DATA STATEWIDE
SHOWS THE EXTENT OF THE LIGHT AND VARIABLE WINDS AFFECTING MORE
ISLANDS THAN EXPECTED...REACHING OUT TO MOLOKAI AND WEST MAUI.
ALSO...THE AFTERNOON CLOUDS HAVE REACHED THE TWO SUMMITS ON THE BIG
ISLAND INCLUDING A BRIEF SHOWERS ON THE NORTHWEST SIDE OF MAUNA LOA.
SO ADJUSTMENTS HAVE BEEN MADE TO THESE AREAS. INCLUDING A SLIGHT
CHANCE FOR A SHOWER FOR THE SUMMITS FOR THE REST OF THIS AFTERNOON.

ALTHOUGH DIFFICULT TO PIN POINT BUT WE ARE PLACING THE LOW
LEVEL TROUGH OVER KAUAI THIS AFTERNOON AS PER GFS SOLUTION. IT IS
FORECAST TO EASE INTO THE KAUAI CHANNEL SHORTLY AND DISSIPATE THERE
EARLY THIS EVENING.

WATER VAPOR IMAGERY SHOWS THUNDERSTORMS CONTINUING OVER THE OFFSHORE
WATERS NORTH OF MOLOKAI AND MAUI. AN UPPER LEVEL SHORT WAVE TROUGH
IS THE RESPONSIBLE FEATURE FOR THESE STORMS. THE TROUGH IS MOVING
EAST AT 25 MPH...AND AT THIS RATE...PUTS THE UPPER TROUGH JUST EAST
OF THE BIG ISLAND AT 8 PM HST THIS EVENING. SO WITH THE UPPER TROUGH
LIFTING OUT...THE LOW LEVEL TROUGH FILLING...THE LOSS OF DAYTIME
HEATING...AND THE LACK OF SHOWERS...WE ANTICIPATE ANY REMAINING
SHOWERS TO END SHORTLY AFTER THE SUN SETS. IT IS A PRETTY DRY
EASTERLY WIND FLOW EAST OF MOLOKAI AS WELL. SO EXPECT A MAIN DRY
NIGHT ALL AREAS TONIGHT. ANY TRADE SHOWERS WILL LIKELY COME WELL
AFTER MIDNIGHT. EXPECT MORE TRADE SHOWERS FROM WEDNESDAY NIGHT ON.
THE REST OF THE FORECAST REMAINS INTACT WITH STRENGTHENING TRADES
REACHING LOCALLY STRONG OVER THE WATERS AROUND MAUI AND SOUTH OF THE
BIG ISLAND BY WEDNESDAY AFTERNOON. THE TRADES ARE EXPECTED TO SLIP
TO MODERATE SPEEDS FROM FRIDAY ON.

THERE REMAINS SOME DISCREPANCY BETWEEN THE EC AND GFS THURSDAY NIGHT
THROUGH SATURDAY WITH THE GFS BRINGING LIGHTER WINDS OVERALL AND
INCREASED MOISTURE TO THE BIG ISLAND. WE ARE CURRENTLY RIDING THE EC
SOLUTION AND CLIMATOLOGY WITH CONTINUED MODERATE TRADES INTO THE
WEEKEND.

&&

.AVIATION...
AIRMET SIERRA IS IN PLACE FOR ALL OF THE ISLANDS BUT SHOULD BE
LIFTED SOMETIME EARLY THIS EVENING. IT SHOULD BE A RELATIVELY
AIRMET-FREE NIGHT OTHERWISE.

&&

.MARINE...
WINDS WILL REMAIN BELOW SMALL CRAFT ADVISORY /SCA/ SPEEDS THROUGH
TONIGHT. TRADES ARE EXPECTED TO RETURN TO KAUAI AND OAHU BY DAYBREAK
WEDNESDAY AS THE TROUGH NEAR KAUAI AND OAHU DISSIPATES THIS EVENING.
THE TRADES WILL CONTINUE TO STRENGTHEN INTO WEDNESDAY REACHING
LOCALLY STRONG SPEEDS BY THE AFTERNOON...AND A SCA...FOR WATERS
AROUND MAUI AND SOUTH OF THE BIG ISLAND.

THE CURRENT SMALL NORTHWEST SWELL WILL DISSIPATE BY WEDNESDAY. A
SMALL SOUTH-SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER
THE NEXT COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL
FOR THE SECOND HALF OF THE WORK WEEK.

&&

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

&&

$$

DISCUSSION...LAU










000
FXHW60 PHFO 010155
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
330 PM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH NEAR KAUAI IS EXPECTED TO DISSIPATE OVER THE
WESTERN ISLANDS THIS EVENING. THIS WILL ALLOW LOCALLY STRONG TRADES
TO RETURN TO ALL AREAS WEDNESDAY. TRADE WIND CONDITIONS WILL PERSIST
INTO THE WEEKEND WITH SHOWERS FAVORING THE WINDWARD AND MOUNTAIN
AREAS.

&&

.DISCUSSION...
AS OF 3 PM HST...THE AFTERNOON CONVECTION ON KAUAI HAS BE SPOTTY AT
BEST AND CONFINED TO MAINLY THE SOUTHERN HALF OF THE ISLAND. THE
NORTHERN HALF IS PARTLY SUNNY AND MAINLY DRY. ON OAHU...IT HAS BEEN
SPOTTY AS WELL...FAVORING THE WAIANAE AND KOOLAU MOUNTAINS AND
WINDWARD COAST. LANAI HAD A HEAVY SHOWER OR TWO A SHORT TIME AGO
WHILE MOLOKAI AND MAUI HAVE BEEN GENERALLY QUIET...MAY BE A BRIEF
SHOWER OR TWO AT BEST. IN SHORT...SHOWER ACTIVITY IS SOMEWHAT LESS
THAN EXPECTED.

OTHER NOTEWORTHY OBSERVATIONS AS OF 230 PM HST...WIND DATA STATEWIDE
SHOWS THE EXTENT OF THE LIGHT AND VARIABLE WINDS AFFECTING MORE
ISLANDS THAN EXPECTED...REACHING OUT TO MOLOKAI AND WEST MAUI.
ALSO...THE AFTERNOON CLOUDS HAVE REACHED THE TWO SUMMITS ON THE BIG
ISLAND INCLUDING A BRIEF SHOWERS ON THE NORTHWEST SIDE OF MAUNA LOA.
SO ADJUSTMENTS HAVE BEEN MADE TO THESE AREAS. INCLUDING A SLIGHT
CHANCE FOR A SHOWER FOR THE SUMMITS FOR THE REST OF THIS AFTERNOON.

ALTHOUGH DIFFICULT TO PIN POINT BUT WE ARE PLACING THE LOW
LEVEL TROUGH OVER KAUAI THIS AFTERNOON AS PER GFS SOLUTION. IT IS
FORECAST TO EASE INTO THE KAUAI CHANNEL SHORTLY AND DISSIPATE THERE
EARLY THIS EVENING.

WATER VAPOR IMAGERY SHOWS THUNDERSTORMS CONTINUING OVER THE OFFSHORE
WATERS NORTH OF MOLOKAI AND MAUI. AN UPPER LEVEL SHORT WAVE TROUGH
IS THE RESPONSIBLE FEATURE FOR THESE STORMS. THE TROUGH IS MOVING
EAST AT 25 MPH...AND AT THIS RATE...PUTS THE UPPER TROUGH JUST EAST
OF THE BIG ISLAND AT 8 PM HST THIS EVENING. SO WITH THE UPPER TROUGH
LIFTING OUT...THE LOW LEVEL TROUGH FILLING...THE LOSS OF DAYTIME
HEATING...AND THE LACK OF SHOWERS...WE ANTICIPATE ANY REMAINING
SHOWERS TO END SHORTLY AFTER THE SUN SETS. IT IS A PRETTY DRY
EASTERLY WIND FLOW EAST OF MOLOKAI AS WELL. SO EXPECT A MAIN DRY
NIGHT ALL AREAS TONIGHT. ANY TRADE SHOWERS WILL LIKELY COME WELL
AFTER MIDNIGHT. EXPECT MORE TRADE SHOWERS FROM WEDNESDAY NIGHT ON.
THE REST OF THE FORECAST REMAINS INTACT WITH STRENGTHENING TRADES
REACHING LOCALLY STRONG OVER THE WATERS AROUND MAUI AND SOUTH OF THE
BIG ISLAND BY WEDNESDAY AFTERNOON. THE TRADES ARE EXPECTED TO SLIP
TO MODERATE SPEEDS FROM FRIDAY ON.

THERE REMAINS SOME DISCREPANCY BETWEEN THE EC AND GFS THURSDAY NIGHT
THROUGH SATURDAY WITH THE GFS BRINGING LIGHTER WINDS OVERALL AND
INCREASED MOISTURE TO THE BIG ISLAND. WE ARE CURRENTLY RIDING THE EC
SOLUTION AND CLIMATOLOGY WITH CONTINUED MODERATE TRADES INTO THE
WEEKEND.

&&

.AVIATION...
AIRMET SIERRA IS IN PLACE FOR ALL OF THE ISLANDS BUT SHOULD BE
LIFTED SOMETIME EARLY THIS EVENING. IT SHOULD BE A RELATIVELY
AIRMET-FREE NIGHT OTHERWISE.

&&

.MARINE...
WINDS WILL REMAIN BELOW SMALL CRAFT ADVISORY /SCA/ SPEEDS THROUGH
TONIGHT. TRADES ARE EXPECTED TO RETURN TO KAUAI AND OAHU BY DAYBREAK
WEDNESDAY AS THE TROUGH NEAR KAUAI AND OAHU DISSIPATES THIS EVENING.
THE TRADES WILL CONTINUE TO STRENGTHEN INTO WEDNESDAY REACHING
LOCALLY STRONG SPEEDS BY THE AFTERNOON...AND A SCA...FOR WATERS
AROUND MAUI AND SOUTH OF THE BIG ISLAND.

THE CURRENT SMALL NORTHWEST SWELL WILL DISSIPATE BY WEDNESDAY. A
SMALL SOUTH-SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER
THE NEXT COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL
FOR THE SECOND HALF OF THE WORK WEEK.

&&

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

&&

$$

DISCUSSION...LAU











000
FXHW60 PHFO 312008
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH NEAR KAUAI IS EXPECTED TO DISSIPATE OVER THE
WESTERN ISLANDS TODAY AND THIS EVENING. THIS WILL ALLOW LOCALLY
STRONG TRADES TO RETURN TO ALL AREAS WEDNESDAY. TRADE WIND
CONDITIONS WILL PERSIST INTO THE WEEKEND WITH SHOWERS FAVORING THE
WINDWARD AND MOUNTAIN AREAS.

&&

.DISCUSSION...
WIND SENSORS ON KAUAI SHOWS A PREDOMINANTLY LIGHT SOUTHERLY WIND
FLOW AT OR NEAR THE SURFACE. THIS MEANS A LOW LEVEL TROUGH IS
NEARBY... PERHAPS JUST WEST OF KAUAI. THE GFS SHOWS THE TROUGH...AND
HAS AN OVERALL BETTER ASSESSMENT THAN THE ECMWF /EC/. THE GFS POINTS
TO THE TROUGH MOVING OVER KAUAI THIS AFTERNOON BEFORE DISSIPATING
OVER OAHU THIS EVENING. IN ESSENCE...THERE WILL BE LIGHT AND
VARIABLE WINDS OVER THE AREA WEST OF MOLOKAI THIS AFTERNOON AND
EVENING.

THE LOW LEVEL TROUGH IS BEING AIDED BY ANY UPPER LEVEL SHORTWAVE
TROUGH CURRENTLY PASSING NORTH OF KAUAI. THIS DISTURBANCE IS SETTING
OFF ISOLATED THUNDERSTORMS OVER THE OFFSHORE WATERS NORTH AND
NORTHEAST OF KAUAI...AND HAD TRIGGERED SOME LOCALLY HEAVY SHOWERS
EARLIER THIS MORNING ON KAUAI AND OAHU.

WE ARE NOT EXPECTING THUNDERSTORMS THIS AFTERNOON AS MOST OF THE
INSTABILITY FROM THE UPPER TROUGH REMAINS NORTH OF THE ISLANDS.
MOISTURE AVAILABILITY IS LIMITED AT 1.25 INCHES PRECIP WATERS... AND
REACHES NO HIGHER THAN 15K FEET. HOWEVER... THE LOW LEVEL TROUGH AND
ISLAND HEATING WILL BRING INCREASED SHOWER ACTIVITY THIS AFTERNOON
ESPECIALLY FOR KAUAI AND OAHU.

ELSEWHERE...WINDS FROM MOLOKAI EASTWARD WILL REMAIN UNDER LIGHT TO
MODERATE EAST TO SOUTHEAST WINDS THROUGH TONIGHT. AS THE LOW LEVEL
TROUGH DISSIPATES ...TRADES WILL SPREAD WESTWARD REACHING KAUAI BY
SUNRISE WEDNESDAY. ADDITIONALLY TRADES WILL STRENGTHEN TO LOCALLY
STRONG OVER THE WATERS AROUND MAUI AND SOUTH OF THE BIG ISLAND
WEDNESDAY.

THE TRADE WIND REGIME IS EXPECTED TO CONTINUE INTO THE WEEKEND WITH
SHOWERS FAVORING THE WINDWARD AND MOUNTAIN AREAS...ESPECIALLY NIGHTS
AND MORNINGS. HOWEVER...THERE IS SOME DISCREPANCY BETWEEN THE EC AND
GFS THURSDAY NIGHT THROUGH SATURDAY WITH THE GFS BRINGING LIGHTER
WINDS OVERALL AND INCREASED MOISTURE TO THE BIG ISLAND. WE ARE
CURRENTLY RIDING THE EC SOLUTION AND CLIMATOLOGY WITH CONTINUED
MODERATE TRADES INTO THE WEEKEND.

&&

.AVIATION...
NO AIRMETS CURRENTLY IN EFFECT. BUT AN AIRMET FOR MTN OBSCURATION IS
LIKELY FOR KAUAI AND OAHU THIS AFTERNOON AND EARLY EVENING AS AMPLE
MOISTURE...LIGHT WINDS...DAYTIME HEATING...AIDED BY A TROUGH RESULTS
IN A SHOWERY AFTERNOON FOR ESPECIALLY THESE TWO ISLANDS.


&&

.MARINE...
WINDS WILL REMAIN BELOW SMALL CRAFT ADVISORY /SCA/ SPEEDS THROUGH
TONIGHT. TRADES ARE EXPECTED TO RETURN TO KAUAI AND OAHU BY DAYBREAK
WEDNESDAY AS THE TROUGH NEAR KAUAI AND OAHU DISSIPATES THIS EVENING.
THE TRADES WILL CONTINUE TO STRENGTHEN INTO WEDNESDAY REACHING
LOCALLY STRONG SPEEDS BY THE AFTERNOON...AND A SCA...FOR WATERS
AROUND MAUI AND SOUTH OF THE BIG ISLAND.

THE CURRENT SMALL NORTHWEST SWELL WILL DISSIPATE BY WEDNESDAY. A
SMALL SOUTH-SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER
THE NEXT COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL
FOR THE SECOND HALF OF THE WORK WEEK.

&&

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

&&

$$

DISCUSSION...LAU










000
FXHW60 PHFO 312008
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH NEAR KAUAI IS EXPECTED TO DISSIPATE OVER THE
WESTERN ISLANDS TODAY AND THIS EVENING. THIS WILL ALLOW LOCALLY
STRONG TRADES TO RETURN TO ALL AREAS WEDNESDAY. TRADE WIND
CONDITIONS WILL PERSIST INTO THE WEEKEND WITH SHOWERS FAVORING THE
WINDWARD AND MOUNTAIN AREAS.

&&

.DISCUSSION...
WIND SENSORS ON KAUAI SHOWS A PREDOMINANTLY LIGHT SOUTHERLY WIND
FLOW AT OR NEAR THE SURFACE. THIS MEANS A LOW LEVEL TROUGH IS
NEARBY... PERHAPS JUST WEST OF KAUAI. THE GFS SHOWS THE TROUGH...AND
HAS AN OVERALL BETTER ASSESSMENT THAN THE ECMWF /EC/. THE GFS POINTS
TO THE TROUGH MOVING OVER KAUAI THIS AFTERNOON BEFORE DISSIPATING
OVER OAHU THIS EVENING. IN ESSENCE...THERE WILL BE LIGHT AND
VARIABLE WINDS OVER THE AREA WEST OF MOLOKAI THIS AFTERNOON AND
EVENING.

THE LOW LEVEL TROUGH IS BEING AIDED BY ANY UPPER LEVEL SHORTWAVE
TROUGH CURRENTLY PASSING NORTH OF KAUAI. THIS DISTURBANCE IS SETTING
OFF ISOLATED THUNDERSTORMS OVER THE OFFSHORE WATERS NORTH AND
NORTHEAST OF KAUAI...AND HAD TRIGGERED SOME LOCALLY HEAVY SHOWERS
EARLIER THIS MORNING ON KAUAI AND OAHU.

WE ARE NOT EXPECTING THUNDERSTORMS THIS AFTERNOON AS MOST OF THE
INSTABILITY FROM THE UPPER TROUGH REMAINS NORTH OF THE ISLANDS.
MOISTURE AVAILABILITY IS LIMITED AT 1.25 INCHES PRECIP WATERS... AND
REACHES NO HIGHER THAN 15K FEET. HOWEVER... THE LOW LEVEL TROUGH AND
ISLAND HEATING WILL BRING INCREASED SHOWER ACTIVITY THIS AFTERNOON
ESPECIALLY FOR KAUAI AND OAHU.

ELSEWHERE...WINDS FROM MOLOKAI EASTWARD WILL REMAIN UNDER LIGHT TO
MODERATE EAST TO SOUTHEAST WINDS THROUGH TONIGHT. AS THE LOW LEVEL
TROUGH DISSIPATES ...TRADES WILL SPREAD WESTWARD REACHING KAUAI BY
SUNRISE WEDNESDAY. ADDITIONALLY TRADES WILL STRENGTHEN TO LOCALLY
STRONG OVER THE WATERS AROUND MAUI AND SOUTH OF THE BIG ISLAND
WEDNESDAY.

THE TRADE WIND REGIME IS EXPECTED TO CONTINUE INTO THE WEEKEND WITH
SHOWERS FAVORING THE WINDWARD AND MOUNTAIN AREAS...ESPECIALLY NIGHTS
AND MORNINGS. HOWEVER...THERE IS SOME DISCREPANCY BETWEEN THE EC AND
GFS THURSDAY NIGHT THROUGH SATURDAY WITH THE GFS BRINGING LIGHTER
WINDS OVERALL AND INCREASED MOISTURE TO THE BIG ISLAND. WE ARE
CURRENTLY RIDING THE EC SOLUTION AND CLIMATOLOGY WITH CONTINUED
MODERATE TRADES INTO THE WEEKEND.

&&

.AVIATION...
NO AIRMETS CURRENTLY IN EFFECT. BUT AN AIRMET FOR MTN OBSCURATION IS
LIKELY FOR KAUAI AND OAHU THIS AFTERNOON AND EARLY EVENING AS AMPLE
MOISTURE...LIGHT WINDS...DAYTIME HEATING...AIDED BY A TROUGH RESULTS
IN A SHOWERY AFTERNOON FOR ESPECIALLY THESE TWO ISLANDS.


&&

.MARINE...
WINDS WILL REMAIN BELOW SMALL CRAFT ADVISORY /SCA/ SPEEDS THROUGH
TONIGHT. TRADES ARE EXPECTED TO RETURN TO KAUAI AND OAHU BY DAYBREAK
WEDNESDAY AS THE TROUGH NEAR KAUAI AND OAHU DISSIPATES THIS EVENING.
THE TRADES WILL CONTINUE TO STRENGTHEN INTO WEDNESDAY REACHING
LOCALLY STRONG SPEEDS BY THE AFTERNOON...AND A SCA...FOR WATERS
AROUND MAUI AND SOUTH OF THE BIG ISLAND.

THE CURRENT SMALL NORTHWEST SWELL WILL DISSIPATE BY WEDNESDAY. A
SMALL SOUTH-SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER
THE NEXT COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL
FOR THE SECOND HALF OF THE WORK WEEK.

&&

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

&&

$$

DISCUSSION...LAU









000
FXHW60 PHFO 312000
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
920 AM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH NEAR KAUAI IS EXPECTED TO DISSIPATE OVER THE
WESTERN ISLANDS TODAY AND THIS EVENING. THIS WILL ALLOW TRADES
LOCALLY STRONG TRADES TO RETURN ALL AREAS BY SUNRISE WEDNESDAY.
TRADE WINDS CONDITIONS WILL PERSIST INTO THE WEEKEND WITH SHOWERS
FAVORING THE WINDWARD AND MOUNTAIN AREAS.

&&

.DISCUSSION...
WIND SENSORS ON KAUAI SHOWS A PREDOMINANT LIGHT SOUTHERLY WIND FLOW
AT OR NEAR THE SURFACE. THIS MEANS A LOW LEVEL TROUGH IS NEARBY...
PERHAPS JUST WEST OF KAUAI. THE GFS SHOWS THIS...AND HAS AN OVERALL
BETTER WIND ASSESSMENT THAN THE ECMWF /EC/. THE GFS POINTS TO THE
TROUGH MOVING OVER KAUAI THIS AFTERNOON BEFORE DISSIPATING OVER OAHU
THIS EVENING. IN ESSENCE...IT WILL BE LIGHT VARIABLE WINDS OVER THE
AREA WEST OF MOLOKAI FOR THIS AFTERNOON AND EVENING.

THE LOW LEVEL TROUGH IS BEING AIDED BY ANY UPPER LEVEL SHORTWAVE
TROUGH CURRENTLY PASSING NORTH OF KAUAI. THIS DISTURBANCE IS SETTING
OFF ISOLATED THUNDERSTORMS OVER THE OFFSHORE WATERS NORTH AND
NORTHEAST OF KAUAI...AND HAD TRIGGERED SOME LOCALLY HEAVY SHOWERS
EARLIER THIS MORNING ON KAUAI AND OAHU.

WE ARE NOT EXPECTING THUNDERSTORMS FOR THE ISLANDS THIS AFTERNOON.
THE CORE OF THE DYNAMICS IS EXPECTED TO STAY NORTH OF THE ISLANDS.
MOISTURE AVAILABILITY IS SOMEWHAT LIMITED AT 1.25 INCHES PRECIP
WATERS...AND NO HIGHER THAN 15K FEET. BUT WE ARE EXPECTING AN
ACTIVE SHOWERY AFTERNOON HOWEVER FOR ESPECIALLY KAUAI AND OAHU. WE
ARE MONITORING A LINE OF SHOWERS CURRENTLY IN THE KAUAI CHANNEL
ADVANCING TOWARDS OAHU.

ELSEWHERE...WINDS FROM MOLOKAI EASTWARD WILL REMAIN UNDER LIGHT TO
MODERATE EAST TO SOUTHEAST WINDS THROUGH TONIGHT. AS THE TROUGH
FILLS...TRADES WILL SPREAD WESTWARD REACHING KAUAI BY SUNRISE
WEDNESDAY. ADDITIONALLY TRADES WILL STRENGTHEN TO LOCALLY STRONG
OVER THE WATERS AROUND MAUI AND SOUTH OF THE BIG ISLAND ON WEDNESDAY.

WITH SOME RESERVATIONS....THIS TRADE WIND REGIME IS EXPECTED TO
CONTINUE INTO THIS WEEKEND WITH SHOWERS FAVORING THE WINDWARD AND
MOUNTAIN AREAS...ESPECIALLY NIGHT AND MORNINGS. THIS RESERVATION IS
FOR THE FORECAST PERIOD BETWEEN THURSDAY NIGHT AND SATURDAY DUE TO
THE DISAGREEMENT BETWEEN THE EC AND GFS. WE ARE CURRENTLY
RIDING WITH THE EC SOLUTION WITH MODERATE TRADES INTO THE WEEKEND.
THE GFS ON THE OTHER HAND HAS LIGHT WINDS AREA WIDE WITH UNSETTLE
WEATHER FOR THE BIG ISLAND. MODERATE TRADES RETURNS ON SUNDAY
LASTING THROUGH EARLY NEXT WEEK. BUT UNTIL FURTHER NOTICE...WE WILL
STAY WITH THE MORE POSITIVE EC SOLUTION.

&&

.AVIATION...
NO AIRMETS CURRENTLY IN EFFECT. BUT AIRMET FOR MTN OBSCURATION IS
LIKELY FOR KAUAI AND OAHU THIS AFTERNOON AND EARLY EVENING AS AMPLE
MOISTURE...LIGHT WINDS...DAYTIME HEATING...AIDED BY A TROUGH RESULTS
IN A SHOWERY AFTERNOON FOR ESPECIALLY THESE TWO ISLANDS.


&&

.MARINE...
WINDS WILL REMAIN BELOW SMALL CRAFT ADVISORY /SCA/ SPEEDS THROUGH
TONIGHT. TRADES ARE EXPECTED TO RETURN TO KAUAI AND OAHU BY DAYBREAK
WEDNESDAY AS THE TROUGH NEAR KAUAI AND OAHU DISSIPATES THIS EVENING.
THE TRADES WILL CONTINUE TO STRENGTHEN INTO WEDNESDAY REACHING
LOCALLY STRONG SPEEDS BY THE AFTERNOON...AND AN SCA...FOR WATERS
AROUND MAUI AND SOUTH OF THE BIG ISLAND.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE THIS AFTERNOON
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK.

&&

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

&&

$$

DISCUSSION...LAU








000
FXHW60 PHFO 312000
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
920 AM HST TUE MAR 31 2015

.SYNOPSIS...
A LOW LEVEL TROUGH NEAR KAUAI IS EXPECTED TO DISSIPATE OVER THE
WESTERN ISLANDS TODAY AND THIS EVENING. THIS WILL ALLOW TRADES
LOCALLY STRONG TRADES TO RETURN ALL AREAS BY SUNRISE WEDNESDAY.
TRADE WINDS CONDITIONS WILL PERSIST INTO THE WEEKEND WITH SHOWERS
FAVORING THE WINDWARD AND MOUNTAIN AREAS.

&&

.DISCUSSION...
WIND SENSORS ON KAUAI SHOWS A PREDOMINANT LIGHT SOUTHERLY WIND FLOW
AT OR NEAR THE SURFACE. THIS MEANS A LOW LEVEL TROUGH IS NEARBY...
PERHAPS JUST WEST OF KAUAI. THE GFS SHOWS THIS...AND HAS AN OVERALL
BETTER WIND ASSESSMENT THAN THE ECMWF /EC/. THE GFS POINTS TO THE
TROUGH MOVING OVER KAUAI THIS AFTERNOON BEFORE DISSIPATING OVER OAHU
THIS EVENING. IN ESSENCE...IT WILL BE LIGHT VARIABLE WINDS OVER THE
AREA WEST OF MOLOKAI FOR THIS AFTERNOON AND EVENING.

THE LOW LEVEL TROUGH IS BEING AIDED BY ANY UPPER LEVEL SHORTWAVE
TROUGH CURRENTLY PASSING NORTH OF KAUAI. THIS DISTURBANCE IS SETTING
OFF ISOLATED THUNDERSTORMS OVER THE OFFSHORE WATERS NORTH AND
NORTHEAST OF KAUAI...AND HAD TRIGGERED SOME LOCALLY HEAVY SHOWERS
EARLIER THIS MORNING ON KAUAI AND OAHU.

WE ARE NOT EXPECTING THUNDERSTORMS FOR THE ISLANDS THIS AFTERNOON.
THE CORE OF THE DYNAMICS IS EXPECTED TO STAY NORTH OF THE ISLANDS.
MOISTURE AVAILABILITY IS SOMEWHAT LIMITED AT 1.25 INCHES PRECIP
WATERS...AND NO HIGHER THAN 15K FEET. BUT WE ARE EXPECTING AN
ACTIVE SHOWERY AFTERNOON HOWEVER FOR ESPECIALLY KAUAI AND OAHU. WE
ARE MONITORING A LINE OF SHOWERS CURRENTLY IN THE KAUAI CHANNEL
ADVANCING TOWARDS OAHU.

ELSEWHERE...WINDS FROM MOLOKAI EASTWARD WILL REMAIN UNDER LIGHT TO
MODERATE EAST TO SOUTHEAST WINDS THROUGH TONIGHT. AS THE TROUGH
FILLS...TRADES WILL SPREAD WESTWARD REACHING KAUAI BY SUNRISE
WEDNESDAY. ADDITIONALLY TRADES WILL STRENGTHEN TO LOCALLY STRONG
OVER THE WATERS AROUND MAUI AND SOUTH OF THE BIG ISLAND ON WEDNESDAY.

WITH SOME RESERVATIONS....THIS TRADE WIND REGIME IS EXPECTED TO
CONTINUE INTO THIS WEEKEND WITH SHOWERS FAVORING THE WINDWARD AND
MOUNTAIN AREAS...ESPECIALLY NIGHT AND MORNINGS. THIS RESERVATION IS
FOR THE FORECAST PERIOD BETWEEN THURSDAY NIGHT AND SATURDAY DUE TO
THE DISAGREEMENT BETWEEN THE EC AND GFS. WE ARE CURRENTLY
RIDING WITH THE EC SOLUTION WITH MODERATE TRADES INTO THE WEEKEND.
THE GFS ON THE OTHER HAND HAS LIGHT WINDS AREA WIDE WITH UNSETTLE
WEATHER FOR THE BIG ISLAND. MODERATE TRADES RETURNS ON SUNDAY
LASTING THROUGH EARLY NEXT WEEK. BUT UNTIL FURTHER NOTICE...WE WILL
STAY WITH THE MORE POSITIVE EC SOLUTION.

&&

.AVIATION...
NO AIRMETS CURRENTLY IN EFFECT. BUT AIRMET FOR MTN OBSCURATION IS
LIKELY FOR KAUAI AND OAHU THIS AFTERNOON AND EARLY EVENING AS AMPLE
MOISTURE...LIGHT WINDS...DAYTIME HEATING...AIDED BY A TROUGH RESULTS
IN A SHOWERY AFTERNOON FOR ESPECIALLY THESE TWO ISLANDS.


&&

.MARINE...
WINDS WILL REMAIN BELOW SMALL CRAFT ADVISORY /SCA/ SPEEDS THROUGH
TONIGHT. TRADES ARE EXPECTED TO RETURN TO KAUAI AND OAHU BY DAYBREAK
WEDNESDAY AS THE TROUGH NEAR KAUAI AND OAHU DISSIPATES THIS EVENING.
THE TRADES WILL CONTINUE TO STRENGTHEN INTO WEDNESDAY REACHING
LOCALLY STRONG SPEEDS BY THE AFTERNOON...AND AN SCA...FOR WATERS
AROUND MAUI AND SOUTH OF THE BIG ISLAND.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE THIS AFTERNOON
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK.

&&

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

&&

$$

DISCUSSION...LAU









000
FXHW60 PHFO 311725
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
720 AM HST TUE MAR 31 2015

.UPDATE...
THE ZONES HAVE BEEN UPDATED FOR KAUAI...WINDWARD BIG ISLAND AND
WINDWARD MAUI WHERE POPS AND SKY COVERAGE HAVE BEEN REDUCED.
THE BACKGROUND WINDS HAVE BEEN ADJUSTED FOR THE TODAY PERIOD...FROM
EASTERLY TO LIGHT AND VARIABLE FOR ESPECIALLY WATERS WEST OF MAUI.

THE AFTERNOON PORTION OF THE FORECAST REMAINS INTACT. CONDITIONS
REMAINS RIPE FOR MORE WIDESPREAD SHOWER ACTIVITY FOR THE SMALLER
ISLANDS THIS AFTERNOON.

&&

.SYNOPSIS...
SOUTHEASTERLY WINDS WILL FURTHER WEAKEN TODAY...ALLOWING FOR PERIODS
OF AFTERNOON SEA BREEZES AND SCATTERED SHOWERS TO DEVELOP OVER
LEEWARD AND INTERIOR SECTIONS. BEST CHANCES OF RAIN REMAIN OVER
KAUAI AND OAHU. THE EASTERLY TRADES WILL BEGIN RETURNING TONIGHT
AND INTO WEDNESDAY...WITH SHOWERS AGAIN FAVORING WINDWARD AND MAUKA
AREAS DURING THE LATER PART OF THE WEEK.

&&

.DISCUSSION...
A SFC HIGH PRESSURE SYSTEM CENTERED FAR N OF THE ALOHA STATE IS
KEEPING A GENERALLY E FLOW ACROSS THE AREA. HOWEVER...AN UPPER LVL
SHORTWAVE FEATURE AND ITS ASSOCIATED LOW LVL TROUGH MOVING JUST N
OF KAUAI ARE DISRUPTING THE FLOW ACROSS THE SMALLER ISLANDS AND
VEERING WINDS TO THE SE. THE SHORTWAVE IS RIDING ALONG THE
SUBTROPICAL JET N OF THE AREA...AND WILL KEEP MIGRATING E DURING
THE NEXT COUPLE OF DAYS. THE INFLUENCE OF THESE FEATURES WILL
CONTINUE TO SUPPORT A WETTER PATTERN ACROSS THE ISLANDS TODAY.

FOR THIS MORNING...BEST CHANCES OF RAIN REMAIN OVER WINDWARD AND
MAUKA AREAS OF THE SMALLER ISLANDS. LOCALIZED HEAVY RAIN AND WIDE
SPREAD SHOWERS ACROSS MUCH OF KAUAI PROMPTED THE ISSUANCE OF A FLOOD
ADVISORY DURING THE OVERNIGHT HOURS. AT 3 AM HST DATA FROM THE
DOPPLER RADAR NETWORK CONTINUE TO SHOW SHOWERS FOCUSING OVER THE S
AND CENTRAL HALF OF THE KOOLAU RANGE IN OAHU...THE E MOLOKAI
MOUNTAINS AND THE W MAUI MOUNTAINS. LOCALIZED HEAVY RAIN WAS
AFFECTING SE PORTIONS OF KAUAI NEAR KIPU FALLS...AND WIDE SPREAD
MODERATE RAIN LINGERED OVER MUCH OF INTERIOR KAUAI. SOME OF THE
LARGER SHOWERS ARE REACHING LEEWARD LOCATIONS AT TIMES...INCLUDING
THE HONOLULU METRO AREA.

BY THIS AFTERNOON...THE INFLUENCE OF THE AFOREMENTIONED SHORTWAVE
FEATURE AND THE ASSOCIATED LOW LVL TROUGH WILL FURTHER WEAKEN THE SE
FLOW. THIS WILL ALLOW FOR DAYTIME SEA BREEZE CIRCULATIONS TO DEVELOP
WITH CLOUD BUILD-UPS AND LOCALIZED SHOWERS AFFECTING LEEWARD AND
INTERIOR AREAS. ENHANCED MOISTURE ACCOMPANYING THE TROUGH WILL ALSO
INCREASE CHANCES FOR LOCALIZED HEAVY RAIN...ALTHOUGH ANY DOWNPOURS
THAT MAY DEVELOP SHOULD BE BRIEF.

MODEL GUIDANCE SHOW THE SHORTWAVE AND LOW LVL TROUGH QUICKLY
MIGRATING TO THE NE TONIGHT AND THROUGH WED...ALLOWING FOR THE
TRADES TO RE-ESTABLISH ACROSS THE AREA. THIS WILL BRING BACK THE
MORE TYPICAL WINDWARD/MAUKA SHOWERS FOR THE REST OF THE WORK WEEK.
HOWEVER...THE GLOBAL MODELS SHOW DIFFERENCES IN THE MID/LONG RANGE
SOLUTIONS...WITH GFS BEING MORE AGGRESSIVE IN PUSHING ANOTHER UPPER
LVL TROUGH TO THE N OF THE STATE ON THE THU/FRI TIMEFRAME. THIS
SOLUTION BRINGS THE TROUGH CLOSE ENOUGH TO KAUAI TO AGAIN DISRUPT
THE TRADES. THE REST OF GUIDANCE...ESPECIALLY ECMWF...DOWNPLAY THIS
SCENARIO AND KEEP THE TRADES IN PLACE THROUGH FRI. ATTM...THE
OFFICIAL FORECAST WILL CONTINUE TO FOLLOW THE ECMWF SOLUTION WITH A
TRADE WIND WEATHER REGIME PREVAILING THROUGH THE REST OF THE WORK
WEEK. BUT THE FORECAST PHILOSOPHY COULD CHANGE IF FUTURE MODEL RUNS
BEGIN TRENDING TOWARDS GFS.

MODELS ALSO SUGGEST THE POTENTIAL FOR AN AREA OF ENHANCED MOISTURE
APPROACHING THE STATE FROM THE SE FOR THE UPCOMING WEEKEND...WHICH
COULD BRING AN INCREASE IN SHOWERS ESPECIALLY OVER THE BIG ISLAND.

&&

.AVIATION...
A DISTURBANCE ALOFT PASSING N OF THE ISLANDS TODAY WILL BRING
INCREASED MOISTURE AND INSTABILITY...AND LIGHTER TRADE WINDS.
THIS WILL LEAD TO TEMPO MVFR VIS/CIG IN SHRA AND ISOL IFR VIS/CIG IN
+SHRA...ESPECIALLY OVER KAUAI AND OAHU. ALTHOUGH CLOUDS AND SHRA
WILL PRIMARILY FOCUS ACROSS WINDWARD...LEEWARD AREAS WILL ALSO BE
IMPACTED. AIRMET SIERRA FOR MTN OBSC IS IN PLACE FOR MOST AREAS...
AND IS EXPECTED TO REMAIN IN PLACE TODAY.

WHILE VFR WILL PREVAIL AT THE TERMINALS...PERIODS OF MVFR VIS/CIG
CAN BE EXPECTED AT PHTO AND PHLI.

&&

.MARINE...
WIND SPEEDS OVER THE ALENUIHAHA CHANNEL AND THE WATERS SOUTH OF THE
BIG ISLAND ARE NOW DROPPING BELOW ADVISORY LEVELS. THUS...THE SMALL
CRAFT ADVISORY IS NO LONGER IN EFFECT FOR THOSE WATERS.
HOWEVER...WINDS ARE EXPECTED TO INCREASE AGAIN ON WEDNESDAY...AND
LIKELY REACHING ADVISORY LEVELS OVER THE TYPICALLY WINDIER WATERS
AROUND THE BIG ISLAND AND MAUI COUNTY.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE TODAY AND
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK.

&&

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

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD







000
FXHW60 PHFO 311725
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
720 AM HST TUE MAR 31 2015

.UPDATE...
THE ZONES HAVE BEEN UPDATED FOR KAUAI...WINDWARD BIG ISLAND AND
WINDWARD MAUI WHERE POPS AND SKY COVERAGE HAVE BEEN REDUCED.
THE BACKGROUND WINDS HAVE BEEN ADJUSTED FOR THE TODAY PERIOD...FROM
EASTERLY TO LIGHT AND VARIABLE FOR ESPECIALLY WATERS WEST OF MAUI.

THE AFTERNOON PORTION OF THE FORECAST REMAINS INTACT. CONDITIONS
REMAINS RIPE FOR MORE WIDESPREAD SHOWER ACTIVITY FOR THE SMALLER
ISLANDS THIS AFTERNOON.

&&

.SYNOPSIS...
SOUTHEASTERLY WINDS WILL FURTHER WEAKEN TODAY...ALLOWING FOR PERIODS
OF AFTERNOON SEA BREEZES AND SCATTERED SHOWERS TO DEVELOP OVER
LEEWARD AND INTERIOR SECTIONS. BEST CHANCES OF RAIN REMAIN OVER
KAUAI AND OAHU. THE EASTERLY TRADES WILL BEGIN RETURNING TONIGHT
AND INTO WEDNESDAY...WITH SHOWERS AGAIN FAVORING WINDWARD AND MAUKA
AREAS DURING THE LATER PART OF THE WEEK.

&&

.DISCUSSION...
A SFC HIGH PRESSURE SYSTEM CENTERED FAR N OF THE ALOHA STATE IS
KEEPING A GENERALLY E FLOW ACROSS THE AREA. HOWEVER...AN UPPER LVL
SHORTWAVE FEATURE AND ITS ASSOCIATED LOW LVL TROUGH MOVING JUST N
OF KAUAI ARE DISRUPTING THE FLOW ACROSS THE SMALLER ISLANDS AND
VEERING WINDS TO THE SE. THE SHORTWAVE IS RIDING ALONG THE
SUBTROPICAL JET N OF THE AREA...AND WILL KEEP MIGRATING E DURING
THE NEXT COUPLE OF DAYS. THE INFLUENCE OF THESE FEATURES WILL
CONTINUE TO SUPPORT A WETTER PATTERN ACROSS THE ISLANDS TODAY.

FOR THIS MORNING...BEST CHANCES OF RAIN REMAIN OVER WINDWARD AND
MAUKA AREAS OF THE SMALLER ISLANDS. LOCALIZED HEAVY RAIN AND WIDE
SPREAD SHOWERS ACROSS MUCH OF KAUAI PROMPTED THE ISSUANCE OF A FLOOD
ADVISORY DURING THE OVERNIGHT HOURS. AT 3 AM HST DATA FROM THE
DOPPLER RADAR NETWORK CONTINUE TO SHOW SHOWERS FOCUSING OVER THE S
AND CENTRAL HALF OF THE KOOLAU RANGE IN OAHU...THE E MOLOKAI
MOUNTAINS AND THE W MAUI MOUNTAINS. LOCALIZED HEAVY RAIN WAS
AFFECTING SE PORTIONS OF KAUAI NEAR KIPU FALLS...AND WIDE SPREAD
MODERATE RAIN LINGERED OVER MUCH OF INTERIOR KAUAI. SOME OF THE
LARGER SHOWERS ARE REACHING LEEWARD LOCATIONS AT TIMES...INCLUDING
THE HONOLULU METRO AREA.

BY THIS AFTERNOON...THE INFLUENCE OF THE AFOREMENTIONED SHORTWAVE
FEATURE AND THE ASSOCIATED LOW LVL TROUGH WILL FURTHER WEAKEN THE SE
FLOW. THIS WILL ALLOW FOR DAYTIME SEA BREEZE CIRCULATIONS TO DEVELOP
WITH CLOUD BUILD-UPS AND LOCALIZED SHOWERS AFFECTING LEEWARD AND
INTERIOR AREAS. ENHANCED MOISTURE ACCOMPANYING THE TROUGH WILL ALSO
INCREASE CHANCES FOR LOCALIZED HEAVY RAIN...ALTHOUGH ANY DOWNPOURS
THAT MAY DEVELOP SHOULD BE BRIEF.

MODEL GUIDANCE SHOW THE SHORTWAVE AND LOW LVL TROUGH QUICKLY
MIGRATING TO THE NE TONIGHT AND THROUGH WED...ALLOWING FOR THE
TRADES TO RE-ESTABLISH ACROSS THE AREA. THIS WILL BRING BACK THE
MORE TYPICAL WINDWARD/MAUKA SHOWERS FOR THE REST OF THE WORK WEEK.
HOWEVER...THE GLOBAL MODELS SHOW DIFFERENCES IN THE MID/LONG RANGE
SOLUTIONS...WITH GFS BEING MORE AGGRESSIVE IN PUSHING ANOTHER UPPER
LVL TROUGH TO THE N OF THE STATE ON THE THU/FRI TIMEFRAME. THIS
SOLUTION BRINGS THE TROUGH CLOSE ENOUGH TO KAUAI TO AGAIN DISRUPT
THE TRADES. THE REST OF GUIDANCE...ESPECIALLY ECMWF...DOWNPLAY THIS
SCENARIO AND KEEP THE TRADES IN PLACE THROUGH FRI. ATTM...THE
OFFICIAL FORECAST WILL CONTINUE TO FOLLOW THE ECMWF SOLUTION WITH A
TRADE WIND WEATHER REGIME PREVAILING THROUGH THE REST OF THE WORK
WEEK. BUT THE FORECAST PHILOSOPHY COULD CHANGE IF FUTURE MODEL RUNS
BEGIN TRENDING TOWARDS GFS.

MODELS ALSO SUGGEST THE POTENTIAL FOR AN AREA OF ENHANCED MOISTURE
APPROACHING THE STATE FROM THE SE FOR THE UPCOMING WEEKEND...WHICH
COULD BRING AN INCREASE IN SHOWERS ESPECIALLY OVER THE BIG ISLAND.

&&

.AVIATION...
A DISTURBANCE ALOFT PASSING N OF THE ISLANDS TODAY WILL BRING
INCREASED MOISTURE AND INSTABILITY...AND LIGHTER TRADE WINDS.
THIS WILL LEAD TO TEMPO MVFR VIS/CIG IN SHRA AND ISOL IFR VIS/CIG IN
+SHRA...ESPECIALLY OVER KAUAI AND OAHU. ALTHOUGH CLOUDS AND SHRA
WILL PRIMARILY FOCUS ACROSS WINDWARD...LEEWARD AREAS WILL ALSO BE
IMPACTED. AIRMET SIERRA FOR MTN OBSC IS IN PLACE FOR MOST AREAS...
AND IS EXPECTED TO REMAIN IN PLACE TODAY.

WHILE VFR WILL PREVAIL AT THE TERMINALS...PERIODS OF MVFR VIS/CIG
CAN BE EXPECTED AT PHTO AND PHLI.

&&

.MARINE...
WIND SPEEDS OVER THE ALENUIHAHA CHANNEL AND THE WATERS SOUTH OF THE
BIG ISLAND ARE NOW DROPPING BELOW ADVISORY LEVELS. THUS...THE SMALL
CRAFT ADVISORY IS NO LONGER IN EFFECT FOR THOSE WATERS.
HOWEVER...WINDS ARE EXPECTED TO INCREASE AGAIN ON WEDNESDAY...AND
LIKELY REACHING ADVISORY LEVELS OVER THE TYPICALLY WINDIER WATERS
AROUND THE BIG ISLAND AND MAUI COUNTY.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE TODAY AND
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK.

&&

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

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD








000
FXHW60 PHFO 311725
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
720 AM HST TUE MAR 31 2015

.UPDATE...
THE ZONES HAVE BEEN UPDATED FOR KAUAI...WINDWARD BIG ISLAND AND
WINDWARD MAUI WHERE POPS AND SKY COVERAGE HAVE BEEN REDUCED.
THE BACKGROUND WINDS HAVE BEEN ADJUSTED FOR THE TODAY PERIOD...FROM
EASTERLY TO LIGHT AND VARIABLE FOR ESPECIALLY WATERS WEST OF MAUI.

THE AFTERNOON PORTION OF THE FORECAST REMAINS INTACT. CONDITIONS
REMAINS RIPE FOR MORE WIDESPREAD SHOWER ACTIVITY FOR THE SMALLER
ISLANDS THIS AFTERNOON.

&&

.SYNOPSIS...
SOUTHEASTERLY WINDS WILL FURTHER WEAKEN TODAY...ALLOWING FOR PERIODS
OF AFTERNOON SEA BREEZES AND SCATTERED SHOWERS TO DEVELOP OVER
LEEWARD AND INTERIOR SECTIONS. BEST CHANCES OF RAIN REMAIN OVER
KAUAI AND OAHU. THE EASTERLY TRADES WILL BEGIN RETURNING TONIGHT
AND INTO WEDNESDAY...WITH SHOWERS AGAIN FAVORING WINDWARD AND MAUKA
AREAS DURING THE LATER PART OF THE WEEK.

&&

.DISCUSSION...
A SFC HIGH PRESSURE SYSTEM CENTERED FAR N OF THE ALOHA STATE IS
KEEPING A GENERALLY E FLOW ACROSS THE AREA. HOWEVER...AN UPPER LVL
SHORTWAVE FEATURE AND ITS ASSOCIATED LOW LVL TROUGH MOVING JUST N
OF KAUAI ARE DISRUPTING THE FLOW ACROSS THE SMALLER ISLANDS AND
VEERING WINDS TO THE SE. THE SHORTWAVE IS RIDING ALONG THE
SUBTROPICAL JET N OF THE AREA...AND WILL KEEP MIGRATING E DURING
THE NEXT COUPLE OF DAYS. THE INFLUENCE OF THESE FEATURES WILL
CONTINUE TO SUPPORT A WETTER PATTERN ACROSS THE ISLANDS TODAY.

FOR THIS MORNING...BEST CHANCES OF RAIN REMAIN OVER WINDWARD AND
MAUKA AREAS OF THE SMALLER ISLANDS. LOCALIZED HEAVY RAIN AND WIDE
SPREAD SHOWERS ACROSS MUCH OF KAUAI PROMPTED THE ISSUANCE OF A FLOOD
ADVISORY DURING THE OVERNIGHT HOURS. AT 3 AM HST DATA FROM THE
DOPPLER RADAR NETWORK CONTINUE TO SHOW SHOWERS FOCUSING OVER THE S
AND CENTRAL HALF OF THE KOOLAU RANGE IN OAHU...THE E MOLOKAI
MOUNTAINS AND THE W MAUI MOUNTAINS. LOCALIZED HEAVY RAIN WAS
AFFECTING SE PORTIONS OF KAUAI NEAR KIPU FALLS...AND WIDE SPREAD
MODERATE RAIN LINGERED OVER MUCH OF INTERIOR KAUAI. SOME OF THE
LARGER SHOWERS ARE REACHING LEEWARD LOCATIONS AT TIMES...INCLUDING
THE HONOLULU METRO AREA.

BY THIS AFTERNOON...THE INFLUENCE OF THE AFOREMENTIONED SHORTWAVE
FEATURE AND THE ASSOCIATED LOW LVL TROUGH WILL FURTHER WEAKEN THE SE
FLOW. THIS WILL ALLOW FOR DAYTIME SEA BREEZE CIRCULATIONS TO DEVELOP
WITH CLOUD BUILD-UPS AND LOCALIZED SHOWERS AFFECTING LEEWARD AND
INTERIOR AREAS. ENHANCED MOISTURE ACCOMPANYING THE TROUGH WILL ALSO
INCREASE CHANCES FOR LOCALIZED HEAVY RAIN...ALTHOUGH ANY DOWNPOURS
THAT MAY DEVELOP SHOULD BE BRIEF.

MODEL GUIDANCE SHOW THE SHORTWAVE AND LOW LVL TROUGH QUICKLY
MIGRATING TO THE NE TONIGHT AND THROUGH WED...ALLOWING FOR THE
TRADES TO RE-ESTABLISH ACROSS THE AREA. THIS WILL BRING BACK THE
MORE TYPICAL WINDWARD/MAUKA SHOWERS FOR THE REST OF THE WORK WEEK.
HOWEVER...THE GLOBAL MODELS SHOW DIFFERENCES IN THE MID/LONG RANGE
SOLUTIONS...WITH GFS BEING MORE AGGRESSIVE IN PUSHING ANOTHER UPPER
LVL TROUGH TO THE N OF THE STATE ON THE THU/FRI TIMEFRAME. THIS
SOLUTION BRINGS THE TROUGH CLOSE ENOUGH TO KAUAI TO AGAIN DISRUPT
THE TRADES. THE REST OF GUIDANCE...ESPECIALLY ECMWF...DOWNPLAY THIS
SCENARIO AND KEEP THE TRADES IN PLACE THROUGH FRI. ATTM...THE
OFFICIAL FORECAST WILL CONTINUE TO FOLLOW THE ECMWF SOLUTION WITH A
TRADE WIND WEATHER REGIME PREVAILING THROUGH THE REST OF THE WORK
WEEK. BUT THE FORECAST PHILOSOPHY COULD CHANGE IF FUTURE MODEL RUNS
BEGIN TRENDING TOWARDS GFS.

MODELS ALSO SUGGEST THE POTENTIAL FOR AN AREA OF ENHANCED MOISTURE
APPROACHING THE STATE FROM THE SE FOR THE UPCOMING WEEKEND...WHICH
COULD BRING AN INCREASE IN SHOWERS ESPECIALLY OVER THE BIG ISLAND.

&&

.AVIATION...
A DISTURBANCE ALOFT PASSING N OF THE ISLANDS TODAY WILL BRING
INCREASED MOISTURE AND INSTABILITY...AND LIGHTER TRADE WINDS.
THIS WILL LEAD TO TEMPO MVFR VIS/CIG IN SHRA AND ISOL IFR VIS/CIG IN
+SHRA...ESPECIALLY OVER KAUAI AND OAHU. ALTHOUGH CLOUDS AND SHRA
WILL PRIMARILY FOCUS ACROSS WINDWARD...LEEWARD AREAS WILL ALSO BE
IMPACTED. AIRMET SIERRA FOR MTN OBSC IS IN PLACE FOR MOST AREAS...
AND IS EXPECTED TO REMAIN IN PLACE TODAY.

WHILE VFR WILL PREVAIL AT THE TERMINALS...PERIODS OF MVFR VIS/CIG
CAN BE EXPECTED AT PHTO AND PHLI.

&&

.MARINE...
WIND SPEEDS OVER THE ALENUIHAHA CHANNEL AND THE WATERS SOUTH OF THE
BIG ISLAND ARE NOW DROPPING BELOW ADVISORY LEVELS. THUS...THE SMALL
CRAFT ADVISORY IS NO LONGER IN EFFECT FOR THOSE WATERS.
HOWEVER...WINDS ARE EXPECTED TO INCREASE AGAIN ON WEDNESDAY...AND
LIKELY REACHING ADVISORY LEVELS OVER THE TYPICALLY WINDIER WATERS
AROUND THE BIG ISLAND AND MAUI COUNTY.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE TODAY AND
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK.

&&

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

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD








000
FXHW60 PHFO 311346
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
340 AM HST TUE MAR 31 2015

.SYNOPSIS...
SOUTHEASTERLY WINDS WILL FURTHER WEAKEN TODAY...ALLOWING FOR PERIODS
OF AFTERNOON SEA BREEZES AND SCATTERED SHOWERS TO DEVELOP OVER
LEEWARD AND INTERIOR SECTIONS. BEST CHANCES OF RAIN REMAIN OVER
KAUAI AND OAHU. THE EASTERLY TRADES WILL BEGIN RETURNING TONIGHT
AND INTO WEDNESDAY...WITH SHOWERS AGAIN FAVORING WINDWARD AND MAUKA
AREAS DURING THE LATER PART OF THE WEEK.

&&

.DISCUSSION...
A SFC HIGH PRESSURE SYSTEM CENTERED FAR N OF THE ALOHA STATE IS
KEEPING A GENERALLY E FLOW ACROSS THE AREA. HOWEVER...AN UPPER LVL
SHORTWAVE FEATURE AND ITS ASSOCIATED LOW LVL TROUGH MOVING JUST N
OF KAUAI ARE DISRUPTING THE FLOW ACROSS THE SMALLER ISLANDS AND
VEERING WINDS TO THE SE. THE SHORTWAVE IS RIDING ALONG THE
SUBTROPICAL JET N OF THE AREA...AND WILL KEEP MIGRATING E DURING
THE NEXT COUPLE OF DAYS. THE INFLUENCE OF THESE FEATURES WILL
CONTINUE TO SUPPORT A WETTER PATTERN ACROSS THE ISLANDS TODAY.

FOR THIS MORNING...BEST CHANCES OF RAIN REMAIN OVER WINDWARD AND
MAUKA AREAS OF THE SMALLER ISLANDS. LOCALIZED HEAVY RAIN AND WIDE
SPREAD SHOWERS ACROSS MUCH OF KAUAI PROMPTED THE ISSUANCE OF A FLOOD
ADVISORY DURING THE OVERNIGHT HOURS. AT 3 AM HST DATA FROM THE
DOPPLER RADAR NETWORK CONTINUE TO SHOW SHOWERS FOCUSING OVER THE S
AND CENTRAL HALF OF THE KOOLAU RANGE IN OAHU...THE E MOLOKAI
MOUNTAINS AND THE W MAUI MOUNTAINS. LOCALIZED HEAVY RAIN WAS
AFFECTING SE PORTIONS OF KAUAI NEAR KIPU FALLS...AND WIDE SPREAD
MODERATE RAIN LINGERED OVER MUCH OF INTERIOR KAUAI. SOME OF THE
LARGER SHOWERS ARE REACHING LEEWARD LOCATIONS AT TIMES...INCLUDING
THE HONOLULU METRO AREA.

BY THIS AFTERNOON...THE INFLUENCE OF THE AFOREMENTIONED SHORTWAVE
FEATURE AND THE ASSOCIATED LOW LVL TROUGH WILL FURTHER WEAKEN THE SE
FLOW. THIS WILL ALLOW FOR DAYTIME SEA BREEZE CIRCULATIONS TO DEVELOP
WITH CLOUD BUILD-UPS AND LOCALIZED SHOWERS AFFECTING LEEWARD AND
INTERIOR AREAS. ENHANCED MOISTURE ACCOMPANYING THE TROUGH WILL ALSO
INCREASE CHANCES FOR LOCALIZED HEAVY RAIN...ALTHOUGH ANY DOWNPOURS
THAT MAY DEVELOP SHOULD BE BRIEF.

MODEL GUIDANCE SHOW THE SHORTWAVE AND LOW LVL TROUGH QUICKLY
MIGRATING TO THE NE TONIGHT AND THROUGH WED...ALLOWING FOR THE
TRADES TO RE-ESTABLISH ACROSS THE AREA. THIS WILL BRING BACK THE
MORE TYPICAL WINDWARD/MAUKA SHOWERS FOR THE REST OF THE WORK WEEK.
HOWEVER...THE GLOBAL MODELS SHOW DIFFERENCES IN THE MID/LONG RANGE
SOLUTIONS...WITH GFS BEING MORE AGGRESSIVE IN PUSHING ANOTHER UPPER
LVL TROUGH TO THE N OF THE STATE ON THE THU/FRI TIMEFRAME. THIS
SOLUTION BRINGS THE TROUGH CLOSE ENOUGH TO KAUAI TO AGAIN DISRUPT
THE TRADES. THE REST OF GUIDANCE...ESPECIALLY ECMWF...DOWNPLAY THIS
SCENARIO AND KEEP THE TRADES IN PLACE THROUGH FRI. ATTM...THE
OFFICIAL FORECAST WILL CONTINUE TO FOLLOW THE ECMWF SOLUTION WITH A
TRADE WIND WEATHER REGIME PREVAILING THROUGH THE REST OF THE WORK
WEEK. BUT THE FORECAST PHILOSOPHY COULD CHANGE IF FUTURE MODEL RUNS
BEGIN TRENDING TOWARDS GFS.

MODELS ALSO SUGGEST THE POTENTIAL FOR AN AREA OF ENHANCED MOISTURE
APPROACHING THE STATE FROM THE SE FOR THE UPCOMING WEEKEND...WHICH
COULD BRING AN INCREASE IN SHOWERS ESPECIALLY OVER THE BIG ISLAND.

&&

.AVIATION...
A DISTURBANCE ALOFT PASSING N OF THE ISLANDS TODAY WILL BRING
INCREASED MOISTURE AND INSTABILITY...AND LIGHTER TRADE WINDS.
THIS WILL LEAD TO TEMPO MVFR VIS/CIG IN SHRA AND ISOL IFR VIS/CIG IN
+SHRA...ESPECIALLY OVER KAUAI AND OAHU. ALTHOUGH CLOUDS AND SHRA
WILL PRIMARILY FOCUS ACROSS WINDWARD...LEEWARD AREAS WILL ALSO BE
IMPACTED. AIRMET SIERRA FOR MTN OBSC IS IN PLACE FOR MOST AREAS...
AND IS EXPECTED TO REMAIN IN PLACE TODAY.

WHILE VFR WILL PREVAIL AT THE TERMINALS...PERIODS OF MVFR VIS/CIG
CAN BE EXPECTED AT PHTO AND PHLI.

&&

.MARINE...
WIND SPEEDS OVER THE ALENUIHAHA CHANNEL AND THE WATERS SOUTH OF THE
BIG ISLAND ARE NOW DROPPING BELOW ADVISORY LEVELS. THUS...THE SMALL
CRAFT ADVISORY IS NO LONGER IN EFFECT FOR THOSE WATERS.
HOWEVER...WINDS ARE EXPECTED TO INCREASE AGAIN ON WEDNESDAY...AND
LIKELY REACHING ADVISORY LEVELS OVER THE TYPICALLY WINDIER WATERS
AROUND THE BIG ISLAND AND MAUI COUNTY.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE TODAY AND
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK.

&&

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

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD








000
FXHW60 PHFO 311346
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
340 AM HST TUE MAR 31 2015

.SYNOPSIS...
SOUTHEASTERLY WINDS WILL FURTHER WEAKEN TODAY...ALLOWING FOR PERIODS
OF AFTERNOON SEA BREEZES AND SCATTERED SHOWERS TO DEVELOP OVER
LEEWARD AND INTERIOR SECTIONS. BEST CHANCES OF RAIN REMAIN OVER
KAUAI AND OAHU. THE EASTERLY TRADES WILL BEGIN RETURNING TONIGHT
AND INTO WEDNESDAY...WITH SHOWERS AGAIN FAVORING WINDWARD AND MAUKA
AREAS DURING THE LATER PART OF THE WEEK.

&&

.DISCUSSION...
A SFC HIGH PRESSURE SYSTEM CENTERED FAR N OF THE ALOHA STATE IS
KEEPING A GENERALLY E FLOW ACROSS THE AREA. HOWEVER...AN UPPER LVL
SHORTWAVE FEATURE AND ITS ASSOCIATED LOW LVL TROUGH MOVING JUST N
OF KAUAI ARE DISRUPTING THE FLOW ACROSS THE SMALLER ISLANDS AND
VEERING WINDS TO THE SE. THE SHORTWAVE IS RIDING ALONG THE
SUBTROPICAL JET N OF THE AREA...AND WILL KEEP MIGRATING E DURING
THE NEXT COUPLE OF DAYS. THE INFLUENCE OF THESE FEATURES WILL
CONTINUE TO SUPPORT A WETTER PATTERN ACROSS THE ISLANDS TODAY.

FOR THIS MORNING...BEST CHANCES OF RAIN REMAIN OVER WINDWARD AND
MAUKA AREAS OF THE SMALLER ISLANDS. LOCALIZED HEAVY RAIN AND WIDE
SPREAD SHOWERS ACROSS MUCH OF KAUAI PROMPTED THE ISSUANCE OF A FLOOD
ADVISORY DURING THE OVERNIGHT HOURS. AT 3 AM HST DATA FROM THE
DOPPLER RADAR NETWORK CONTINUE TO SHOW SHOWERS FOCUSING OVER THE S
AND CENTRAL HALF OF THE KOOLAU RANGE IN OAHU...THE E MOLOKAI
MOUNTAINS AND THE W MAUI MOUNTAINS. LOCALIZED HEAVY RAIN WAS
AFFECTING SE PORTIONS OF KAUAI NEAR KIPU FALLS...AND WIDE SPREAD
MODERATE RAIN LINGERED OVER MUCH OF INTERIOR KAUAI. SOME OF THE
LARGER SHOWERS ARE REACHING LEEWARD LOCATIONS AT TIMES...INCLUDING
THE HONOLULU METRO AREA.

BY THIS AFTERNOON...THE INFLUENCE OF THE AFOREMENTIONED SHORTWAVE
FEATURE AND THE ASSOCIATED LOW LVL TROUGH WILL FURTHER WEAKEN THE SE
FLOW. THIS WILL ALLOW FOR DAYTIME SEA BREEZE CIRCULATIONS TO DEVELOP
WITH CLOUD BUILD-UPS AND LOCALIZED SHOWERS AFFECTING LEEWARD AND
INTERIOR AREAS. ENHANCED MOISTURE ACCOMPANYING THE TROUGH WILL ALSO
INCREASE CHANCES FOR LOCALIZED HEAVY RAIN...ALTHOUGH ANY DOWNPOURS
THAT MAY DEVELOP SHOULD BE BRIEF.

MODEL GUIDANCE SHOW THE SHORTWAVE AND LOW LVL TROUGH QUICKLY
MIGRATING TO THE NE TONIGHT AND THROUGH WED...ALLOWING FOR THE
TRADES TO RE-ESTABLISH ACROSS THE AREA. THIS WILL BRING BACK THE
MORE TYPICAL WINDWARD/MAUKA SHOWERS FOR THE REST OF THE WORK WEEK.
HOWEVER...THE GLOBAL MODELS SHOW DIFFERENCES IN THE MID/LONG RANGE
SOLUTIONS...WITH GFS BEING MORE AGGRESSIVE IN PUSHING ANOTHER UPPER
LVL TROUGH TO THE N OF THE STATE ON THE THU/FRI TIMEFRAME. THIS
SOLUTION BRINGS THE TROUGH CLOSE ENOUGH TO KAUAI TO AGAIN DISRUPT
THE TRADES. THE REST OF GUIDANCE...ESPECIALLY ECMWF...DOWNPLAY THIS
SCENARIO AND KEEP THE TRADES IN PLACE THROUGH FRI. ATTM...THE
OFFICIAL FORECAST WILL CONTINUE TO FOLLOW THE ECMWF SOLUTION WITH A
TRADE WIND WEATHER REGIME PREVAILING THROUGH THE REST OF THE WORK
WEEK. BUT THE FORECAST PHILOSOPHY COULD CHANGE IF FUTURE MODEL RUNS
BEGIN TRENDING TOWARDS GFS.

MODELS ALSO SUGGEST THE POTENTIAL FOR AN AREA OF ENHANCED MOISTURE
APPROACHING THE STATE FROM THE SE FOR THE UPCOMING WEEKEND...WHICH
COULD BRING AN INCREASE IN SHOWERS ESPECIALLY OVER THE BIG ISLAND.

&&

.AVIATION...
A DISTURBANCE ALOFT PASSING N OF THE ISLANDS TODAY WILL BRING
INCREASED MOISTURE AND INSTABILITY...AND LIGHTER TRADE WINDS.
THIS WILL LEAD TO TEMPO MVFR VIS/CIG IN SHRA AND ISOL IFR VIS/CIG IN
+SHRA...ESPECIALLY OVER KAUAI AND OAHU. ALTHOUGH CLOUDS AND SHRA
WILL PRIMARILY FOCUS ACROSS WINDWARD...LEEWARD AREAS WILL ALSO BE
IMPACTED. AIRMET SIERRA FOR MTN OBSC IS IN PLACE FOR MOST AREAS...
AND IS EXPECTED TO REMAIN IN PLACE TODAY.

WHILE VFR WILL PREVAIL AT THE TERMINALS...PERIODS OF MVFR VIS/CIG
CAN BE EXPECTED AT PHTO AND PHLI.

&&

.MARINE...
WIND SPEEDS OVER THE ALENUIHAHA CHANNEL AND THE WATERS SOUTH OF THE
BIG ISLAND ARE NOW DROPPING BELOW ADVISORY LEVELS. THUS...THE SMALL
CRAFT ADVISORY IS NO LONGER IN EFFECT FOR THOSE WATERS.
HOWEVER...WINDS ARE EXPECTED TO INCREASE AGAIN ON WEDNESDAY...AND
LIKELY REACHING ADVISORY LEVELS OVER THE TYPICALLY WINDIER WATERS
AROUND THE BIG ISLAND AND MAUI COUNTY.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE TODAY AND
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK.

&&

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

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD








000
FXHW60 PHFO 310630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST MON MAR 30 2015

.SYNOPSIS...
EXPECT THE CURRENT MODERATE EASTERLY WINDS TO WEAKEN AND SHIFT TO A
MORE SOUTHEASTERLY FLOW STARTING TONIGHT AND THROUGH TUESDAY. THIS
WILL ALLOW FOR PERIODS OF DAYTIME SEA BREEZES AND SCATTERED
SHOWERS ACROSS LEEWARD AND INTERIOR SECTIONS TUESDAY AFTERNOON AND
EARLY EVENING. BEST CHANCES OF RAIN WILL BE OVER KAUAI AND OAHU.
THE EASTERLY TRADES WILL RETURN ON WEDNESDAY...WITH SHOWERS AGAIN
FAVORING WINDWARD AND MAUKA AREAS DURING THE LATER PART OF THE WEEK.

&&

.DISCUSSION...
BROAD SFC HIGH PRESSURE N OF THE MAIN HAWAIIAN ISLANDS IS KEEPING A
MODERATE TRADE WIND REGIME ACROSS THE AREA. AT THE UPPER LVLS...A
SHORT WAVE TROUGH RIDING ALONG THE SUBTROPICAL JET FAR N OF THE
ISLANDS WILL MOVE CLOSER TO THE STATE AND SUPPORT THE DEVELOPMENT
OF A LOW LEVEL TROUGH...WHICH WILL GRADUALLY MOVE TOWARDS THE
ISLAND CHAIN TONIGHT. THIS SYNOPTIC SCENARIO WILL WEAKEN AND VEER
THE TRADES TO A MORE SE FLOW STARTING TONIGHT...AS WELL AS WEAKEN
THE INVERSIONS CURRENTLY DEPICTED BY THE 00Z SOUNDINGS AT AROUND 8K
FT.

EXPECT BEST CHANCES FOR RAIN TO REMAIN OVER WINDWARD AND MAUKA
AREAS OF THE SMALLER ISLANDS THROUGH TUE MORNING. AT 8 PM HST DATA
FROM THE DOPPLER RADAR NETWORK WAS SHOWING THE MORE ACTIVE SHOWERS
FOCUSING OVER THE S AND CENTRAL HALF OF THE KOOLAU RANGE IN
OAHU...THE E MOLOKAI MOUNTAINS AND THE W MAUI MOUNTAINS. SHOWERS
ALSO LINGER OVER INTERIOR KAUAI. HOWEVER...THE E/SE FLOW WILL REMAIN
STRONG ENOUGH TO PUSH SOME OF THE LARGER SHOWERS INTO LEEWARD
LOCATIONS AT TIMES...INCLUDING THE HONOLULU METRO AREA TONIGHT.

BY TUE LATE MORNING AND INTO THE AFTERNOON...THE INFLUENCE OF THE
AFOREMENTIONED SHORTWAVE FEATURE AND THE ASSOCIATED LOW LVL TROUGH
WILL CAUSE A DISRUPTION OF THE SE FLOW ESPECIALLY ACROSS LEEWARD
AREAS OF THE SMALLER ISLANDS. THUS...DAYTIME SEA BREEZE CIRCULATIONS
ARE LIKELY TO DEVELOP TUE AFTERNOON AND EARLY EVENING...WHICH WILL
BRING CLOUD BUILD-UPS AND LOCALIZED SHOWERS OVER LEEWARD AND
INTERIOR AREAS. ENHANCED MOISTURE ACCOMPANYING THE TROUGH WILL ALSO
INCREASE CHANCES FOR LOCALIZED HEAVY RAIN...ALTHOUGH ANY DOWNPOURS
THAT MAY DEVELOP SHOULD BE BRIEF.

THE SHORTWAVE AND LOW LVL TROUGH QUICKLY MIGRATE TO THE NE TUE
NIGHT AND INTO WED...ALLOWING FOR THE TRADES TO RE-ESTABLISH ACROSS
THE AREA. THIS WILL BRING BACK THE MORE TYPICAL WINDWARD/MAUKA
SHOWERS FOR THE REST OF THE WORK WEEK. HOWEVER...THE GLOBAL MODELS
SHOW DIFFERENCES IN THE MID/LONG RANGE SOLUTIONS...WITH GFS BEING
MORE AGGRESSIVE IN PUSHING ANOTHER UPPER LVL TROUGH TO THE N OF THE
STATE ON THE THU/FRI TIMEFRAME. THIS SOLUTION BRINGS THE TROUGH
CLOSE ENOUGH TO KAUAI TO AGAIN DISRUPT THE TRADES. THE REST OF
GUIDANCE...ESPECIALLY ECMWF...DOWNPLAY THIS SCENARIO AND KEEP THE
TRADES IN PLACE THROUGH FRI. ATTM...THE OFFICIAL FORECAST WILL
CONTINUE TO FOLLOW THE ECMWF SOLUTION WITH A TRADE WIND WEATHER
REGIME PREVAILING THROUGH THE REST OF THE WORK WEEK. BUT THE
FORECAST PHILOSOPHY COULD CHANGE IF FUTURE MODEL RUNS BEGIN
TRENDING TOWARDS GFS. MODELS ALSO SUGGEST THE POTENTIAL FOR AN AREA
OF ENHANCED MOISTURE APPROACHING THE STATE FROM THE SE FOR THE
UPCOMING WEEKEND...WHICH COULD BRING AN INCREASE IN SHOWERS
ESPECIALLY OVER THE BIG ISLAND.

&&

.AVIATION...
A SURFACE TROUGH DEVELOPING NW OF KAUAI WILL BE NEAR THE ISLANDS
TUESDAY...WITH TRADE WINDS DIMINISHING ACROSS THE AREA. DEEPENING
BOUNDARY LAYER MOISTURE AND INCREASED INSTABILITY WILL PRODUCE TEMPO
MVFR VIS/CIG SHRA AND POTENTIALLY ISOL IFR VIS/CIG IN +SHRA.
ALTHOUGH CLOUDS AND SHRA WILL REMAIN FOCUSED ACROSS WINDWARD AND
MAUKA AREAS FOR MUCH OF THE PERIOD...AFTERNOON CLOUDS AND SHRA ARE
EXPECTED OVER LEEWARD AND INTERIOR PORTIONS OF KAUAI AND OAHU
TUESDAY. AIRMET SIERRA FOR MTN OBSC IS IN PLACE FOR MOST AREAS...AND
IS EXPECTED TO REMAIN IN PLACE INTO TUESDAY.

WHILE VFR WILL PREVAIL AT THE TERMINALS...PERIODS OF MVFR VIS/CIG
IN SHRA CAN BE EXPECTED AT PHTO AND PHLI.

&&

.MARINE...
SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE OVER THE ALENUIHAHA
CHANNEL AND THE WATERS SOUTH OF THE BIG ISLAND THROUGH TONIGHT.
AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...WINDS WILL
LIKELY INCREASE INTO ADVISORY LEVELS OVER THE TYPICALLY WINDER
WATERS AROUND THE BIG ISLAND AND MAUI COUNTY ON WEDNESDAY.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE ON TUESDAY AND
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK. ELEVATED WIND SWELL ALONG EAST FACING SHORES WILL DROP A NOTCH
ON TUESDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST TUESDAY FOR THE ALENUIHAHA
CHANNEL AND BIG ISLAND LEEWARD WATERS.

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD








000
FXHW60 PHFO 310630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST MON MAR 30 2015

.SYNOPSIS...
EXPECT THE CURRENT MODERATE EASTERLY WINDS TO WEAKEN AND SHIFT TO A
MORE SOUTHEASTERLY FLOW STARTING TONIGHT AND THROUGH TUESDAY. THIS
WILL ALLOW FOR PERIODS OF DAYTIME SEA BREEZES AND SCATTERED
SHOWERS ACROSS LEEWARD AND INTERIOR SECTIONS TUESDAY AFTERNOON AND
EARLY EVENING. BEST CHANCES OF RAIN WILL BE OVER KAUAI AND OAHU.
THE EASTERLY TRADES WILL RETURN ON WEDNESDAY...WITH SHOWERS AGAIN
FAVORING WINDWARD AND MAUKA AREAS DURING THE LATER PART OF THE WEEK.

&&

.DISCUSSION...
BROAD SFC HIGH PRESSURE N OF THE MAIN HAWAIIAN ISLANDS IS KEEPING A
MODERATE TRADE WIND REGIME ACROSS THE AREA. AT THE UPPER LVLS...A
SHORT WAVE TROUGH RIDING ALONG THE SUBTROPICAL JET FAR N OF THE
ISLANDS WILL MOVE CLOSER TO THE STATE AND SUPPORT THE DEVELOPMENT
OF A LOW LEVEL TROUGH...WHICH WILL GRADUALLY MOVE TOWARDS THE
ISLAND CHAIN TONIGHT. THIS SYNOPTIC SCENARIO WILL WEAKEN AND VEER
THE TRADES TO A MORE SE FLOW STARTING TONIGHT...AS WELL AS WEAKEN
THE INVERSIONS CURRENTLY DEPICTED BY THE 00Z SOUNDINGS AT AROUND 8K
FT.

EXPECT BEST CHANCES FOR RAIN TO REMAIN OVER WINDWARD AND MAUKA
AREAS OF THE SMALLER ISLANDS THROUGH TUE MORNING. AT 8 PM HST DATA
FROM THE DOPPLER RADAR NETWORK WAS SHOWING THE MORE ACTIVE SHOWERS
FOCUSING OVER THE S AND CENTRAL HALF OF THE KOOLAU RANGE IN
OAHU...THE E MOLOKAI MOUNTAINS AND THE W MAUI MOUNTAINS. SHOWERS
ALSO LINGER OVER INTERIOR KAUAI. HOWEVER...THE E/SE FLOW WILL REMAIN
STRONG ENOUGH TO PUSH SOME OF THE LARGER SHOWERS INTO LEEWARD
LOCATIONS AT TIMES...INCLUDING THE HONOLULU METRO AREA TONIGHT.

BY TUE LATE MORNING AND INTO THE AFTERNOON...THE INFLUENCE OF THE
AFOREMENTIONED SHORTWAVE FEATURE AND THE ASSOCIATED LOW LVL TROUGH
WILL CAUSE A DISRUPTION OF THE SE FLOW ESPECIALLY ACROSS LEEWARD
AREAS OF THE SMALLER ISLANDS. THUS...DAYTIME SEA BREEZE CIRCULATIONS
ARE LIKELY TO DEVELOP TUE AFTERNOON AND EARLY EVENING...WHICH WILL
BRING CLOUD BUILD-UPS AND LOCALIZED SHOWERS OVER LEEWARD AND
INTERIOR AREAS. ENHANCED MOISTURE ACCOMPANYING THE TROUGH WILL ALSO
INCREASE CHANCES FOR LOCALIZED HEAVY RAIN...ALTHOUGH ANY DOWNPOURS
THAT MAY DEVELOP SHOULD BE BRIEF.

THE SHORTWAVE AND LOW LVL TROUGH QUICKLY MIGRATE TO THE NE TUE
NIGHT AND INTO WED...ALLOWING FOR THE TRADES TO RE-ESTABLISH ACROSS
THE AREA. THIS WILL BRING BACK THE MORE TYPICAL WINDWARD/MAUKA
SHOWERS FOR THE REST OF THE WORK WEEK. HOWEVER...THE GLOBAL MODELS
SHOW DIFFERENCES IN THE MID/LONG RANGE SOLUTIONS...WITH GFS BEING
MORE AGGRESSIVE IN PUSHING ANOTHER UPPER LVL TROUGH TO THE N OF THE
STATE ON THE THU/FRI TIMEFRAME. THIS SOLUTION BRINGS THE TROUGH
CLOSE ENOUGH TO KAUAI TO AGAIN DISRUPT THE TRADES. THE REST OF
GUIDANCE...ESPECIALLY ECMWF...DOWNPLAY THIS SCENARIO AND KEEP THE
TRADES IN PLACE THROUGH FRI. ATTM...THE OFFICIAL FORECAST WILL
CONTINUE TO FOLLOW THE ECMWF SOLUTION WITH A TRADE WIND WEATHER
REGIME PREVAILING THROUGH THE REST OF THE WORK WEEK. BUT THE
FORECAST PHILOSOPHY COULD CHANGE IF FUTURE MODEL RUNS BEGIN
TRENDING TOWARDS GFS. MODELS ALSO SUGGEST THE POTENTIAL FOR AN AREA
OF ENHANCED MOISTURE APPROACHING THE STATE FROM THE SE FOR THE
UPCOMING WEEKEND...WHICH COULD BRING AN INCREASE IN SHOWERS
ESPECIALLY OVER THE BIG ISLAND.

&&

.AVIATION...
A SURFACE TROUGH DEVELOPING NW OF KAUAI WILL BE NEAR THE ISLANDS
TUESDAY...WITH TRADE WINDS DIMINISHING ACROSS THE AREA. DEEPENING
BOUNDARY LAYER MOISTURE AND INCREASED INSTABILITY WILL PRODUCE TEMPO
MVFR VIS/CIG SHRA AND POTENTIALLY ISOL IFR VIS/CIG IN +SHRA.
ALTHOUGH CLOUDS AND SHRA WILL REMAIN FOCUSED ACROSS WINDWARD AND
MAUKA AREAS FOR MUCH OF THE PERIOD...AFTERNOON CLOUDS AND SHRA ARE
EXPECTED OVER LEEWARD AND INTERIOR PORTIONS OF KAUAI AND OAHU
TUESDAY. AIRMET SIERRA FOR MTN OBSC IS IN PLACE FOR MOST AREAS...AND
IS EXPECTED TO REMAIN IN PLACE INTO TUESDAY.

WHILE VFR WILL PREVAIL AT THE TERMINALS...PERIODS OF MVFR VIS/CIG
IN SHRA CAN BE EXPECTED AT PHTO AND PHLI.

&&

.MARINE...
SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE OVER THE ALENUIHAHA
CHANNEL AND THE WATERS SOUTH OF THE BIG ISLAND THROUGH TONIGHT.
AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...WINDS WILL
LIKELY INCREASE INTO ADVISORY LEVELS OVER THE TYPICALLY WINDER
WATERS AROUND THE BIG ISLAND AND MAUI COUNTY ON WEDNESDAY.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE ON TUESDAY AND
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK. ELEVATED WIND SWELL ALONG EAST FACING SHORES WILL DROP A NOTCH
ON TUESDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST TUESDAY FOR THE ALENUIHAHA
CHANNEL AND BIG ISLAND LEEWARD WATERS.

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD







000
FXHW60 PHFO 310630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST MON MAR 30 2015

.SYNOPSIS...
EXPECT THE CURRENT MODERATE EASTERLY WINDS TO WEAKEN AND SHIFT TO A
MORE SOUTHEASTERLY FLOW STARTING TONIGHT AND THROUGH TUESDAY. THIS
WILL ALLOW FOR PERIODS OF DAYTIME SEA BREEZES AND SCATTERED
SHOWERS ACROSS LEEWARD AND INTERIOR SECTIONS TUESDAY AFTERNOON AND
EARLY EVENING. BEST CHANCES OF RAIN WILL BE OVER KAUAI AND OAHU.
THE EASTERLY TRADES WILL RETURN ON WEDNESDAY...WITH SHOWERS AGAIN
FAVORING WINDWARD AND MAUKA AREAS DURING THE LATER PART OF THE WEEK.

&&

.DISCUSSION...
BROAD SFC HIGH PRESSURE N OF THE MAIN HAWAIIAN ISLANDS IS KEEPING A
MODERATE TRADE WIND REGIME ACROSS THE AREA. AT THE UPPER LVLS...A
SHORT WAVE TROUGH RIDING ALONG THE SUBTROPICAL JET FAR N OF THE
ISLANDS WILL MOVE CLOSER TO THE STATE AND SUPPORT THE DEVELOPMENT
OF A LOW LEVEL TROUGH...WHICH WILL GRADUALLY MOVE TOWARDS THE
ISLAND CHAIN TONIGHT. THIS SYNOPTIC SCENARIO WILL WEAKEN AND VEER
THE TRADES TO A MORE SE FLOW STARTING TONIGHT...AS WELL AS WEAKEN
THE INVERSIONS CURRENTLY DEPICTED BY THE 00Z SOUNDINGS AT AROUND 8K
FT.

EXPECT BEST CHANCES FOR RAIN TO REMAIN OVER WINDWARD AND MAUKA
AREAS OF THE SMALLER ISLANDS THROUGH TUE MORNING. AT 8 PM HST DATA
FROM THE DOPPLER RADAR NETWORK WAS SHOWING THE MORE ACTIVE SHOWERS
FOCUSING OVER THE S AND CENTRAL HALF OF THE KOOLAU RANGE IN
OAHU...THE E MOLOKAI MOUNTAINS AND THE W MAUI MOUNTAINS. SHOWERS
ALSO LINGER OVER INTERIOR KAUAI. HOWEVER...THE E/SE FLOW WILL REMAIN
STRONG ENOUGH TO PUSH SOME OF THE LARGER SHOWERS INTO LEEWARD
LOCATIONS AT TIMES...INCLUDING THE HONOLULU METRO AREA TONIGHT.

BY TUE LATE MORNING AND INTO THE AFTERNOON...THE INFLUENCE OF THE
AFOREMENTIONED SHORTWAVE FEATURE AND THE ASSOCIATED LOW LVL TROUGH
WILL CAUSE A DISRUPTION OF THE SE FLOW ESPECIALLY ACROSS LEEWARD
AREAS OF THE SMALLER ISLANDS. THUS...DAYTIME SEA BREEZE CIRCULATIONS
ARE LIKELY TO DEVELOP TUE AFTERNOON AND EARLY EVENING...WHICH WILL
BRING CLOUD BUILD-UPS AND LOCALIZED SHOWERS OVER LEEWARD AND
INTERIOR AREAS. ENHANCED MOISTURE ACCOMPANYING THE TROUGH WILL ALSO
INCREASE CHANCES FOR LOCALIZED HEAVY RAIN...ALTHOUGH ANY DOWNPOURS
THAT MAY DEVELOP SHOULD BE BRIEF.

THE SHORTWAVE AND LOW LVL TROUGH QUICKLY MIGRATE TO THE NE TUE
NIGHT AND INTO WED...ALLOWING FOR THE TRADES TO RE-ESTABLISH ACROSS
THE AREA. THIS WILL BRING BACK THE MORE TYPICAL WINDWARD/MAUKA
SHOWERS FOR THE REST OF THE WORK WEEK. HOWEVER...THE GLOBAL MODELS
SHOW DIFFERENCES IN THE MID/LONG RANGE SOLUTIONS...WITH GFS BEING
MORE AGGRESSIVE IN PUSHING ANOTHER UPPER LVL TROUGH TO THE N OF THE
STATE ON THE THU/FRI TIMEFRAME. THIS SOLUTION BRINGS THE TROUGH
CLOSE ENOUGH TO KAUAI TO AGAIN DISRUPT THE TRADES. THE REST OF
GUIDANCE...ESPECIALLY ECMWF...DOWNPLAY THIS SCENARIO AND KEEP THE
TRADES IN PLACE THROUGH FRI. ATTM...THE OFFICIAL FORECAST WILL
CONTINUE TO FOLLOW THE ECMWF SOLUTION WITH A TRADE WIND WEATHER
REGIME PREVAILING THROUGH THE REST OF THE WORK WEEK. BUT THE
FORECAST PHILOSOPHY COULD CHANGE IF FUTURE MODEL RUNS BEGIN
TRENDING TOWARDS GFS. MODELS ALSO SUGGEST THE POTENTIAL FOR AN AREA
OF ENHANCED MOISTURE APPROACHING THE STATE FROM THE SE FOR THE
UPCOMING WEEKEND...WHICH COULD BRING AN INCREASE IN SHOWERS
ESPECIALLY OVER THE BIG ISLAND.

&&

.AVIATION...
A SURFACE TROUGH DEVELOPING NW OF KAUAI WILL BE NEAR THE ISLANDS
TUESDAY...WITH TRADE WINDS DIMINISHING ACROSS THE AREA. DEEPENING
BOUNDARY LAYER MOISTURE AND INCREASED INSTABILITY WILL PRODUCE TEMPO
MVFR VIS/CIG SHRA AND POTENTIALLY ISOL IFR VIS/CIG IN +SHRA.
ALTHOUGH CLOUDS AND SHRA WILL REMAIN FOCUSED ACROSS WINDWARD AND
MAUKA AREAS FOR MUCH OF THE PERIOD...AFTERNOON CLOUDS AND SHRA ARE
EXPECTED OVER LEEWARD AND INTERIOR PORTIONS OF KAUAI AND OAHU
TUESDAY. AIRMET SIERRA FOR MTN OBSC IS IN PLACE FOR MOST AREAS...AND
IS EXPECTED TO REMAIN IN PLACE INTO TUESDAY.

WHILE VFR WILL PREVAIL AT THE TERMINALS...PERIODS OF MVFR VIS/CIG
IN SHRA CAN BE EXPECTED AT PHTO AND PHLI.

&&

.MARINE...
SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE OVER THE ALENUIHAHA
CHANNEL AND THE WATERS SOUTH OF THE BIG ISLAND THROUGH TONIGHT.
AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...WINDS WILL
LIKELY INCREASE INTO ADVISORY LEVELS OVER THE TYPICALLY WINDER
WATERS AROUND THE BIG ISLAND AND MAUI COUNTY ON WEDNESDAY.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE ON TUESDAY AND
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK. ELEVATED WIND SWELL ALONG EAST FACING SHORES WILL DROP A NOTCH
ON TUESDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST TUESDAY FOR THE ALENUIHAHA
CHANNEL AND BIG ISLAND LEEWARD WATERS.

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD







000
FXHW60 PHFO 310630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST MON MAR 30 2015

.SYNOPSIS...
EXPECT THE CURRENT MODERATE EASTERLY WINDS TO WEAKEN AND SHIFT TO A
MORE SOUTHEASTERLY FLOW STARTING TONIGHT AND THROUGH TUESDAY. THIS
WILL ALLOW FOR PERIODS OF DAYTIME SEA BREEZES AND SCATTERED
SHOWERS ACROSS LEEWARD AND INTERIOR SECTIONS TUESDAY AFTERNOON AND
EARLY EVENING. BEST CHANCES OF RAIN WILL BE OVER KAUAI AND OAHU.
THE EASTERLY TRADES WILL RETURN ON WEDNESDAY...WITH SHOWERS AGAIN
FAVORING WINDWARD AND MAUKA AREAS DURING THE LATER PART OF THE WEEK.

&&

.DISCUSSION...
BROAD SFC HIGH PRESSURE N OF THE MAIN HAWAIIAN ISLANDS IS KEEPING A
MODERATE TRADE WIND REGIME ACROSS THE AREA. AT THE UPPER LVLS...A
SHORT WAVE TROUGH RIDING ALONG THE SUBTROPICAL JET FAR N OF THE
ISLANDS WILL MOVE CLOSER TO THE STATE AND SUPPORT THE DEVELOPMENT
OF A LOW LEVEL TROUGH...WHICH WILL GRADUALLY MOVE TOWARDS THE
ISLAND CHAIN TONIGHT. THIS SYNOPTIC SCENARIO WILL WEAKEN AND VEER
THE TRADES TO A MORE SE FLOW STARTING TONIGHT...AS WELL AS WEAKEN
THE INVERSIONS CURRENTLY DEPICTED BY THE 00Z SOUNDINGS AT AROUND 8K
FT.

EXPECT BEST CHANCES FOR RAIN TO REMAIN OVER WINDWARD AND MAUKA
AREAS OF THE SMALLER ISLANDS THROUGH TUE MORNING. AT 8 PM HST DATA
FROM THE DOPPLER RADAR NETWORK WAS SHOWING THE MORE ACTIVE SHOWERS
FOCUSING OVER THE S AND CENTRAL HALF OF THE KOOLAU RANGE IN
OAHU...THE E MOLOKAI MOUNTAINS AND THE W MAUI MOUNTAINS. SHOWERS
ALSO LINGER OVER INTERIOR KAUAI. HOWEVER...THE E/SE FLOW WILL REMAIN
STRONG ENOUGH TO PUSH SOME OF THE LARGER SHOWERS INTO LEEWARD
LOCATIONS AT TIMES...INCLUDING THE HONOLULU METRO AREA TONIGHT.

BY TUE LATE MORNING AND INTO THE AFTERNOON...THE INFLUENCE OF THE
AFOREMENTIONED SHORTWAVE FEATURE AND THE ASSOCIATED LOW LVL TROUGH
WILL CAUSE A DISRUPTION OF THE SE FLOW ESPECIALLY ACROSS LEEWARD
AREAS OF THE SMALLER ISLANDS. THUS...DAYTIME SEA BREEZE CIRCULATIONS
ARE LIKELY TO DEVELOP TUE AFTERNOON AND EARLY EVENING...WHICH WILL
BRING CLOUD BUILD-UPS AND LOCALIZED SHOWERS OVER LEEWARD AND
INTERIOR AREAS. ENHANCED MOISTURE ACCOMPANYING THE TROUGH WILL ALSO
INCREASE CHANCES FOR LOCALIZED HEAVY RAIN...ALTHOUGH ANY DOWNPOURS
THAT MAY DEVELOP SHOULD BE BRIEF.

THE SHORTWAVE AND LOW LVL TROUGH QUICKLY MIGRATE TO THE NE TUE
NIGHT AND INTO WED...ALLOWING FOR THE TRADES TO RE-ESTABLISH ACROSS
THE AREA. THIS WILL BRING BACK THE MORE TYPICAL WINDWARD/MAUKA
SHOWERS FOR THE REST OF THE WORK WEEK. HOWEVER...THE GLOBAL MODELS
SHOW DIFFERENCES IN THE MID/LONG RANGE SOLUTIONS...WITH GFS BEING
MORE AGGRESSIVE IN PUSHING ANOTHER UPPER LVL TROUGH TO THE N OF THE
STATE ON THE THU/FRI TIMEFRAME. THIS SOLUTION BRINGS THE TROUGH
CLOSE ENOUGH TO KAUAI TO AGAIN DISRUPT THE TRADES. THE REST OF
GUIDANCE...ESPECIALLY ECMWF...DOWNPLAY THIS SCENARIO AND KEEP THE
TRADES IN PLACE THROUGH FRI. ATTM...THE OFFICIAL FORECAST WILL
CONTINUE TO FOLLOW THE ECMWF SOLUTION WITH A TRADE WIND WEATHER
REGIME PREVAILING THROUGH THE REST OF THE WORK WEEK. BUT THE
FORECAST PHILOSOPHY COULD CHANGE IF FUTURE MODEL RUNS BEGIN
TRENDING TOWARDS GFS. MODELS ALSO SUGGEST THE POTENTIAL FOR AN AREA
OF ENHANCED MOISTURE APPROACHING THE STATE FROM THE SE FOR THE
UPCOMING WEEKEND...WHICH COULD BRING AN INCREASE IN SHOWERS
ESPECIALLY OVER THE BIG ISLAND.

&&

.AVIATION...
A SURFACE TROUGH DEVELOPING NW OF KAUAI WILL BE NEAR THE ISLANDS
TUESDAY...WITH TRADE WINDS DIMINISHING ACROSS THE AREA. DEEPENING
BOUNDARY LAYER MOISTURE AND INCREASED INSTABILITY WILL PRODUCE TEMPO
MVFR VIS/CIG SHRA AND POTENTIALLY ISOL IFR VIS/CIG IN +SHRA.
ALTHOUGH CLOUDS AND SHRA WILL REMAIN FOCUSED ACROSS WINDWARD AND
MAUKA AREAS FOR MUCH OF THE PERIOD...AFTERNOON CLOUDS AND SHRA ARE
EXPECTED OVER LEEWARD AND INTERIOR PORTIONS OF KAUAI AND OAHU
TUESDAY. AIRMET SIERRA FOR MTN OBSC IS IN PLACE FOR MOST AREAS...AND
IS EXPECTED TO REMAIN IN PLACE INTO TUESDAY.

WHILE VFR WILL PREVAIL AT THE TERMINALS...PERIODS OF MVFR VIS/CIG
IN SHRA CAN BE EXPECTED AT PHTO AND PHLI.

&&

.MARINE...
SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE OVER THE ALENUIHAHA
CHANNEL AND THE WATERS SOUTH OF THE BIG ISLAND THROUGH TONIGHT.
AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...WINDS WILL
LIKELY INCREASE INTO ADVISORY LEVELS OVER THE TYPICALLY WINDER
WATERS AROUND THE BIG ISLAND AND MAUI COUNTY ON WEDNESDAY.

THE CURRENT NORTHWEST SWELL WILL CONTINUE TO DECREASE ON TUESDAY AND
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE OVER THE NEXT COUPLE OF DAYS...FOLLOWED
BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE SECOND HALF OF THE WORK
WEEK. ELEVATED WIND SWELL ALONG EAST FACING SHORES WILL DROP A NOTCH
ON TUESDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST TUESDAY FOR THE ALENUIHAHA
CHANNEL AND BIG ISLAND LEEWARD WATERS.

&&

$$

DISCUSSION...REYNES
AVIATION...BIRCHARD








000
FXHW60 PHFO 310154
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST MON MAR 30 2015

.SYNOPSIS...
MODERATE EASTERLY TRADE WINDS WILL BE DISRUPTED OVER THE SMALLER
ISLANDS ON TUESDAY...LEADING TO DAYTIME SEA BREEZES AND SCATTERED
SHOWERS ACROSS LEEWARD AND INTERIOR SECTIONS...ESPECIALLY OVER THE
WESTERN END OF THE STATE. TRADE WINDS WILL REBUILD ON WEDNESDAY...
LIKELY RETURNING THE FOCUS FOR RAINFALL TO WINDWARD SLOPES.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
MODERATE EASTERLY TRADE WINDS WILL GRADUALLY SHIFT OUT OF THE EAST-
SOUTHEAST ACROSS THE SMALLER ISLANDS TONIGHT AS A DEVELOPING TROUGH
NEARS. A SPRAWLING SURFACE HIGH LOCATED ABOUT 800 MILES NORTH OF
THE STATE IS DRIVING THE TRADES. MEANWHILE...AN ACTIVE SUBTROPICAL
JET STREAM ALOFT RUNNING NORTH OF THE STATE CONTAINS A SHORTWAVE
TROUGH ABOUT 700 MILES NORTHWEST OF KAUAI. THIS FEATURE IS ALREADY
INDUCING A SURFACE TROUGH ALONG AN OLD FRONTAL BOUNDARY 250 TO 300
MILES NORTHWEST OF KAUAI...AND AS THE SHORTWAVE APPROACHES
TONIGHT...THE SURFACE TROUGH WILL ADVANCE CLOSER...CAUSING THE TRADE
WINDS TO WEAKEN AND SHIFT OUT OF THE EAST-SOUTHEAST ACROSS THE
SMALLER ISLANDS. SHOWERS WILL STILL FAVOR WINDWARD SLOPES THROUGH
MUCH OF THE NIGHT...AND WE WILL HAVE TO CLOSELY MONITOR FOR THE
POTENTIAL PLUME MOISTURE TRIGGERING SOME ACTIVE SHOWERS ACROSS
WINDWARD OAHU AS THE LOW LEVEL INVERSION ERODES FROM ITS CURRENT
8000 FT.

A ROUND OF AFTERNOON SEA BREEZES WITH LEEWARD SHOWERS IS EXPECTED ON
TUESDAY. THE SHORTWAVE ALOFT WILL PASS OVERHEAD...DRAGGING ITS
ASSOCIATED WEAK SURFACE TROUGH NEAR KAUAI AND OAHU AND DISRUPTING
THE TRADE WINDS. AS A RESULT...DAYTIME SEA BREEZES WILL BE SOMEWHAT
WIDESPREAD ON THE SMALLER ISLANDS...ESPECIALLY FOR KAUAI AND OAHU...
LEADING TO AFTERNOON SHOWERS OVER LEEWARD AND INTERIOR SECTIONS. THE
SHORTWAVE WILL SIGNIFICANTLY ERODE THE INVERSION...AND PRECIPITABLE
WATER /PW/ VALUES SHOULD JUMP UP AROUND 25 PERCENT FROM THE CURRENT
SEASONABLE VALUES AROUND 1.1 INCHES. UNDER THESE CONDITIONS...A
BRIEF HAVE DOWNPOUR IS POSSIBLE...BUT WIDESPREAD HEAVY SHOWERS ARE
NOT EXPECTED. EXPECT THE BIG ISLAND TO REMAIN UNDER A MODERATE TRADE
WIND FLOW.

A RATHER TYPICAL TRADE WIND WEATHER PATTERN WILL RETURN TUESDAY
NIGHT AND WEDNESDAY AS THE SHORTWAVE LIFTS OUT TO THE NORTHEAST.
MODERATE EASTERLY TRADE WINDS WILL FILL BACK IN AS THE WEAK SURFACE
TROUGH WASHES OUT...FOCUSING SHOWERS BACK ON WINDWARD SLOPES.

.LONG TERM /THURSDAY THROUGH MONDAY/...
A CONTINUED MODERATE...EASTERLY TRADE WIND FLOW IS DEPICTED IN THE
FORECAST FOR THURSDAY ONWARD...THOUGH UNCERTAINTY IS SOMEWHAT HIGH.
FORECAST MODELS ARE SHOWING DIFFERENCES IN THE EVOLUTION OF THE JET
STREAM...WITH THE GFS PUSHING ANOTHER UPPER LEVEL TROUGH A COUPLE
HUNDRED MILES CLOSER TO THE ISLANDS THAN THE ECMWF AND CANADIAN
MODELS FOR THURSDAY THROUGH FRIDAY. THE GFS SOLUTION WOULD SUGGEST
ANOTHER ROUND OF DISRUPTED TRADES...WHILE THE ECMWF AND CANADIAN
MODELS WOULD TEND TO MAINTAIN MORE STABLE EASTERLY TRADE WINDS.
OVERALL...THE ECMWF IS BEING FAVORED BY NCEP...AND WE HAVE OPTED TO
GO WITH THAT FORECAST. ANOTHER FEATURE TO WATCH IS A POSSIBLE
INCREASE IN LOW LEVEL MOISTURE MOVING IN FROM THE SOUTHEAST THIS
WEEKEND.

&&

.AVIATION...
A TROUGH OF LOW PRESSURE WILL DEVELOP NORTH OF THE STATE TONIGHT
AND TUESDAY...ALLOWING THE TRADE WINDS TO DIMINISH ACROSS THE AREA.
CLOUDS AND SHRA WILL REMAIN FOCUSED ACROSS WINDWARD AND MAUKA AREAS
THROUGH TONIGHT WITH INTERIOR SHOWERS POSSIBLE TUESDAY.
PREDOMINANTLY VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH
01/00Z...ALTHOUGH BRIEF MVFR CIGS WILL PERIODICALLY AFFECT PHLI
THROUGH THE NIGHT.

AIRMET SIERRA REMAINS IN EFFECT FOR MTN OBSC ACROSS ALL ISLANDS
WITH THE EXCEPTION OF LANAI AND BIG ISLAND. MTN OBSC WILL LIKELY
REMAIN A PROBLEM ACROSS THE CENTRAL AND NORTHERN ISLANDS THROUGH
THE OVERNIGHT HOURS.

AIRMET TANGO REMAINS IN EFFECT FOR LOW LEVEL TURB THROUGH EARLY THIS
EVENING. TURB SHOULD DECREASE SUFFICIENTLY FOR THE AIRMET TO BE
CANCELLED BY 04Z.

&&

.MARINE...
LOCAL OBSERVATIONS AND AN EARLIER ASCAT PASS SUPPORTED A SMALL CRAFT
ADVISORY /SCA/ FOR THE ALENUIHAHA CHANNEL AND NEAR SOUTH POINT. HIGH
RESOLUTION WRF MODELS SHOW THESE STRONGER WINDS HANGING ON IN THESE
AREAS INTO TONIGHT...SO THE SCA HAS BEEN EXTENDED. THE SCA HAS BEEN
DROPPED FOR THE PAILOLO CHANNEL AND MAALAEA BAY SINCE TRADES WILL BE
VEERING OUT OF THE EAST-SOUTHEAST AND LIKELY NOT AFFECTING THOSE
AREAS TONIGHT. AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...
SCA CONDITIONS WILL LIKELY RETURN TO THE TYPICALLY WINDY WATERS ON
WEDNESDAY...FOLLOWED BY SOME WEAKENING AND VEERING OF THE WINDS
LATER IN THE WEEK.

NO LARGER SWELLS ARE DUE THIS WEEK. A DECLINING NORTHWEST SWELL HAS
RUNNING AROUND 4 TO 5 FT AT 14 SECONDS TODAY. THIS SWELL WILL DROP
ON TUESDAY AND FADE ON WEDNESDAY. A SMALL TO MODERATE SOUTH-
SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER THE NEXT
COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE
SECOND HALF OF THE WORK WEEK. ELEVATED WIND SWELL ALONG EAST FACING
SHORES WILL DROP A NOTCH ON TUESDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST TUESDAY FOR THE ALENUIHAHA
CHANNEL AND BIG ISLAND LEEWARD WATERS.

&&

$$

SHORT TERM LONG TERM AND MARINE...WROE
AVIATION...JELSEMA






000
FXHW60 PHFO 310154
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST MON MAR 30 2015

.SYNOPSIS...
MODERATE EASTERLY TRADE WINDS WILL BE DISRUPTED OVER THE SMALLER
ISLANDS ON TUESDAY...LEADING TO DAYTIME SEA BREEZES AND SCATTERED
SHOWERS ACROSS LEEWARD AND INTERIOR SECTIONS...ESPECIALLY OVER THE
WESTERN END OF THE STATE. TRADE WINDS WILL REBUILD ON WEDNESDAY...
LIKELY RETURNING THE FOCUS FOR RAINFALL TO WINDWARD SLOPES.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
MODERATE EASTERLY TRADE WINDS WILL GRADUALLY SHIFT OUT OF THE EAST-
SOUTHEAST ACROSS THE SMALLER ISLANDS TONIGHT AS A DEVELOPING TROUGH
NEARS. A SPRAWLING SURFACE HIGH LOCATED ABOUT 800 MILES NORTH OF
THE STATE IS DRIVING THE TRADES. MEANWHILE...AN ACTIVE SUBTROPICAL
JET STREAM ALOFT RUNNING NORTH OF THE STATE CONTAINS A SHORTWAVE
TROUGH ABOUT 700 MILES NORTHWEST OF KAUAI. THIS FEATURE IS ALREADY
INDUCING A SURFACE TROUGH ALONG AN OLD FRONTAL BOUNDARY 250 TO 300
MILES NORTHWEST OF KAUAI...AND AS THE SHORTWAVE APPROACHES
TONIGHT...THE SURFACE TROUGH WILL ADVANCE CLOSER...CAUSING THE TRADE
WINDS TO WEAKEN AND SHIFT OUT OF THE EAST-SOUTHEAST ACROSS THE
SMALLER ISLANDS. SHOWERS WILL STILL FAVOR WINDWARD SLOPES THROUGH
MUCH OF THE NIGHT...AND WE WILL HAVE TO CLOSELY MONITOR FOR THE
POTENTIAL PLUME MOISTURE TRIGGERING SOME ACTIVE SHOWERS ACROSS
WINDWARD OAHU AS THE LOW LEVEL INVERSION ERODES FROM ITS CURRENT
8000 FT.

A ROUND OF AFTERNOON SEA BREEZES WITH LEEWARD SHOWERS IS EXPECTED ON
TUESDAY. THE SHORTWAVE ALOFT WILL PASS OVERHEAD...DRAGGING ITS
ASSOCIATED WEAK SURFACE TROUGH NEAR KAUAI AND OAHU AND DISRUPTING
THE TRADE WINDS. AS A RESULT...DAYTIME SEA BREEZES WILL BE SOMEWHAT
WIDESPREAD ON THE SMALLER ISLANDS...ESPECIALLY FOR KAUAI AND OAHU...
LEADING TO AFTERNOON SHOWERS OVER LEEWARD AND INTERIOR SECTIONS. THE
SHORTWAVE WILL SIGNIFICANTLY ERODE THE INVERSION...AND PRECIPITABLE
WATER /PW/ VALUES SHOULD JUMP UP AROUND 25 PERCENT FROM THE CURRENT
SEASONABLE VALUES AROUND 1.1 INCHES. UNDER THESE CONDITIONS...A
BRIEF HAVE DOWNPOUR IS POSSIBLE...BUT WIDESPREAD HEAVY SHOWERS ARE
NOT EXPECTED. EXPECT THE BIG ISLAND TO REMAIN UNDER A MODERATE TRADE
WIND FLOW.

A RATHER TYPICAL TRADE WIND WEATHER PATTERN WILL RETURN TUESDAY
NIGHT AND WEDNESDAY AS THE SHORTWAVE LIFTS OUT TO THE NORTHEAST.
MODERATE EASTERLY TRADE WINDS WILL FILL BACK IN AS THE WEAK SURFACE
TROUGH WASHES OUT...FOCUSING SHOWERS BACK ON WINDWARD SLOPES.

.LONG TERM /THURSDAY THROUGH MONDAY/...
A CONTINUED MODERATE...EASTERLY TRADE WIND FLOW IS DEPICTED IN THE
FORECAST FOR THURSDAY ONWARD...THOUGH UNCERTAINTY IS SOMEWHAT HIGH.
FORECAST MODELS ARE SHOWING DIFFERENCES IN THE EVOLUTION OF THE JET
STREAM...WITH THE GFS PUSHING ANOTHER UPPER LEVEL TROUGH A COUPLE
HUNDRED MILES CLOSER TO THE ISLANDS THAN THE ECMWF AND CANADIAN
MODELS FOR THURSDAY THROUGH FRIDAY. THE GFS SOLUTION WOULD SUGGEST
ANOTHER ROUND OF DISRUPTED TRADES...WHILE THE ECMWF AND CANADIAN
MODELS WOULD TEND TO MAINTAIN MORE STABLE EASTERLY TRADE WINDS.
OVERALL...THE ECMWF IS BEING FAVORED BY NCEP...AND WE HAVE OPTED TO
GO WITH THAT FORECAST. ANOTHER FEATURE TO WATCH IS A POSSIBLE
INCREASE IN LOW LEVEL MOISTURE MOVING IN FROM THE SOUTHEAST THIS
WEEKEND.

&&

.AVIATION...
A TROUGH OF LOW PRESSURE WILL DEVELOP NORTH OF THE STATE TONIGHT
AND TUESDAY...ALLOWING THE TRADE WINDS TO DIMINISH ACROSS THE AREA.
CLOUDS AND SHRA WILL REMAIN FOCUSED ACROSS WINDWARD AND MAUKA AREAS
THROUGH TONIGHT WITH INTERIOR SHOWERS POSSIBLE TUESDAY.
PREDOMINANTLY VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH
01/00Z...ALTHOUGH BRIEF MVFR CIGS WILL PERIODICALLY AFFECT PHLI
THROUGH THE NIGHT.

AIRMET SIERRA REMAINS IN EFFECT FOR MTN OBSC ACROSS ALL ISLANDS
WITH THE EXCEPTION OF LANAI AND BIG ISLAND. MTN OBSC WILL LIKELY
REMAIN A PROBLEM ACROSS THE CENTRAL AND NORTHERN ISLANDS THROUGH
THE OVERNIGHT HOURS.

AIRMET TANGO REMAINS IN EFFECT FOR LOW LEVEL TURB THROUGH EARLY THIS
EVENING. TURB SHOULD DECREASE SUFFICIENTLY FOR THE AIRMET TO BE
CANCELLED BY 04Z.

&&

.MARINE...
LOCAL OBSERVATIONS AND AN EARLIER ASCAT PASS SUPPORTED A SMALL CRAFT
ADVISORY /SCA/ FOR THE ALENUIHAHA CHANNEL AND NEAR SOUTH POINT. HIGH
RESOLUTION WRF MODELS SHOW THESE STRONGER WINDS HANGING ON IN THESE
AREAS INTO TONIGHT...SO THE SCA HAS BEEN EXTENDED. THE SCA HAS BEEN
DROPPED FOR THE PAILOLO CHANNEL AND MAALAEA BAY SINCE TRADES WILL BE
VEERING OUT OF THE EAST-SOUTHEAST AND LIKELY NOT AFFECTING THOSE
AREAS TONIGHT. AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...
SCA CONDITIONS WILL LIKELY RETURN TO THE TYPICALLY WINDY WATERS ON
WEDNESDAY...FOLLOWED BY SOME WEAKENING AND VEERING OF THE WINDS
LATER IN THE WEEK.

NO LARGER SWELLS ARE DUE THIS WEEK. A DECLINING NORTHWEST SWELL HAS
RUNNING AROUND 4 TO 5 FT AT 14 SECONDS TODAY. THIS SWELL WILL DROP
ON TUESDAY AND FADE ON WEDNESDAY. A SMALL TO MODERATE SOUTH-
SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER THE NEXT
COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE
SECOND HALF OF THE WORK WEEK. ELEVATED WIND SWELL ALONG EAST FACING
SHORES WILL DROP A NOTCH ON TUESDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST TUESDAY FOR THE ALENUIHAHA
CHANNEL AND BIG ISLAND LEEWARD WATERS.

&&

$$

SHORT TERM LONG TERM AND MARINE...WROE
AVIATION...JELSEMA







000
FXHW60 PHFO 310154
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST MON MAR 30 2015

.SYNOPSIS...
MODERATE EASTERLY TRADE WINDS WILL BE DISRUPTED OVER THE SMALLER
ISLANDS ON TUESDAY...LEADING TO DAYTIME SEA BREEZES AND SCATTERED
SHOWERS ACROSS LEEWARD AND INTERIOR SECTIONS...ESPECIALLY OVER THE
WESTERN END OF THE STATE. TRADE WINDS WILL REBUILD ON WEDNESDAY...
LIKELY RETURNING THE FOCUS FOR RAINFALL TO WINDWARD SLOPES.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
MODERATE EASTERLY TRADE WINDS WILL GRADUALLY SHIFT OUT OF THE EAST-
SOUTHEAST ACROSS THE SMALLER ISLANDS TONIGHT AS A DEVELOPING TROUGH
NEARS. A SPRAWLING SURFACE HIGH LOCATED ABOUT 800 MILES NORTH OF
THE STATE IS DRIVING THE TRADES. MEANWHILE...AN ACTIVE SUBTROPICAL
JET STREAM ALOFT RUNNING NORTH OF THE STATE CONTAINS A SHORTWAVE
TROUGH ABOUT 700 MILES NORTHWEST OF KAUAI. THIS FEATURE IS ALREADY
INDUCING A SURFACE TROUGH ALONG AN OLD FRONTAL BOUNDARY 250 TO 300
MILES NORTHWEST OF KAUAI...AND AS THE SHORTWAVE APPROACHES
TONIGHT...THE SURFACE TROUGH WILL ADVANCE CLOSER...CAUSING THE TRADE
WINDS TO WEAKEN AND SHIFT OUT OF THE EAST-SOUTHEAST ACROSS THE
SMALLER ISLANDS. SHOWERS WILL STILL FAVOR WINDWARD SLOPES THROUGH
MUCH OF THE NIGHT...AND WE WILL HAVE TO CLOSELY MONITOR FOR THE
POTENTIAL PLUME MOISTURE TRIGGERING SOME ACTIVE SHOWERS ACROSS
WINDWARD OAHU AS THE LOW LEVEL INVERSION ERODES FROM ITS CURRENT
8000 FT.

A ROUND OF AFTERNOON SEA BREEZES WITH LEEWARD SHOWERS IS EXPECTED ON
TUESDAY. THE SHORTWAVE ALOFT WILL PASS OVERHEAD...DRAGGING ITS
ASSOCIATED WEAK SURFACE TROUGH NEAR KAUAI AND OAHU AND DISRUPTING
THE TRADE WINDS. AS A RESULT...DAYTIME SEA BREEZES WILL BE SOMEWHAT
WIDESPREAD ON THE SMALLER ISLANDS...ESPECIALLY FOR KAUAI AND OAHU...
LEADING TO AFTERNOON SHOWERS OVER LEEWARD AND INTERIOR SECTIONS. THE
SHORTWAVE WILL SIGNIFICANTLY ERODE THE INVERSION...AND PRECIPITABLE
WATER /PW/ VALUES SHOULD JUMP UP AROUND 25 PERCENT FROM THE CURRENT
SEASONABLE VALUES AROUND 1.1 INCHES. UNDER THESE CONDITIONS...A
BRIEF HAVE DOWNPOUR IS POSSIBLE...BUT WIDESPREAD HEAVY SHOWERS ARE
NOT EXPECTED. EXPECT THE BIG ISLAND TO REMAIN UNDER A MODERATE TRADE
WIND FLOW.

A RATHER TYPICAL TRADE WIND WEATHER PATTERN WILL RETURN TUESDAY
NIGHT AND WEDNESDAY AS THE SHORTWAVE LIFTS OUT TO THE NORTHEAST.
MODERATE EASTERLY TRADE WINDS WILL FILL BACK IN AS THE WEAK SURFACE
TROUGH WASHES OUT...FOCUSING SHOWERS BACK ON WINDWARD SLOPES.

.LONG TERM /THURSDAY THROUGH MONDAY/...
A CONTINUED MODERATE...EASTERLY TRADE WIND FLOW IS DEPICTED IN THE
FORECAST FOR THURSDAY ONWARD...THOUGH UNCERTAINTY IS SOMEWHAT HIGH.
FORECAST MODELS ARE SHOWING DIFFERENCES IN THE EVOLUTION OF THE JET
STREAM...WITH THE GFS PUSHING ANOTHER UPPER LEVEL TROUGH A COUPLE
HUNDRED MILES CLOSER TO THE ISLANDS THAN THE ECMWF AND CANADIAN
MODELS FOR THURSDAY THROUGH FRIDAY. THE GFS SOLUTION WOULD SUGGEST
ANOTHER ROUND OF DISRUPTED TRADES...WHILE THE ECMWF AND CANADIAN
MODELS WOULD TEND TO MAINTAIN MORE STABLE EASTERLY TRADE WINDS.
OVERALL...THE ECMWF IS BEING FAVORED BY NCEP...AND WE HAVE OPTED TO
GO WITH THAT FORECAST. ANOTHER FEATURE TO WATCH IS A POSSIBLE
INCREASE IN LOW LEVEL MOISTURE MOVING IN FROM THE SOUTHEAST THIS
WEEKEND.

&&

.AVIATION...
A TROUGH OF LOW PRESSURE WILL DEVELOP NORTH OF THE STATE TONIGHT
AND TUESDAY...ALLOWING THE TRADE WINDS TO DIMINISH ACROSS THE AREA.
CLOUDS AND SHRA WILL REMAIN FOCUSED ACROSS WINDWARD AND MAUKA AREAS
THROUGH TONIGHT WITH INTERIOR SHOWERS POSSIBLE TUESDAY.
PREDOMINANTLY VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH
01/00Z...ALTHOUGH BRIEF MVFR CIGS WILL PERIODICALLY AFFECT PHLI
THROUGH THE NIGHT.

AIRMET SIERRA REMAINS IN EFFECT FOR MTN OBSC ACROSS ALL ISLANDS
WITH THE EXCEPTION OF LANAI AND BIG ISLAND. MTN OBSC WILL LIKELY
REMAIN A PROBLEM ACROSS THE CENTRAL AND NORTHERN ISLANDS THROUGH
THE OVERNIGHT HOURS.

AIRMET TANGO REMAINS IN EFFECT FOR LOW LEVEL TURB THROUGH EARLY THIS
EVENING. TURB SHOULD DECREASE SUFFICIENTLY FOR THE AIRMET TO BE
CANCELLED BY 04Z.

&&

.MARINE...
LOCAL OBSERVATIONS AND AN EARLIER ASCAT PASS SUPPORTED A SMALL CRAFT
ADVISORY /SCA/ FOR THE ALENUIHAHA CHANNEL AND NEAR SOUTH POINT. HIGH
RESOLUTION WRF MODELS SHOW THESE STRONGER WINDS HANGING ON IN THESE
AREAS INTO TONIGHT...SO THE SCA HAS BEEN EXTENDED. THE SCA HAS BEEN
DROPPED FOR THE PAILOLO CHANNEL AND MAALAEA BAY SINCE TRADES WILL BE
VEERING OUT OF THE EAST-SOUTHEAST AND LIKELY NOT AFFECTING THOSE
AREAS TONIGHT. AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...
SCA CONDITIONS WILL LIKELY RETURN TO THE TYPICALLY WINDY WATERS ON
WEDNESDAY...FOLLOWED BY SOME WEAKENING AND VEERING OF THE WINDS
LATER IN THE WEEK.

NO LARGER SWELLS ARE DUE THIS WEEK. A DECLINING NORTHWEST SWELL HAS
RUNNING AROUND 4 TO 5 FT AT 14 SECONDS TODAY. THIS SWELL WILL DROP
ON TUESDAY AND FADE ON WEDNESDAY. A SMALL TO MODERATE SOUTH-
SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER THE NEXT
COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE
SECOND HALF OF THE WORK WEEK. ELEVATED WIND SWELL ALONG EAST FACING
SHORES WILL DROP A NOTCH ON TUESDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST TUESDAY FOR THE ALENUIHAHA
CHANNEL AND BIG ISLAND LEEWARD WATERS.

&&

$$

SHORT TERM LONG TERM AND MARINE...WROE
AVIATION...JELSEMA







000
FXHW60 PHFO 310154
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST MON MAR 30 2015

.SYNOPSIS...
MODERATE EASTERLY TRADE WINDS WILL BE DISRUPTED OVER THE SMALLER
ISLANDS ON TUESDAY...LEADING TO DAYTIME SEA BREEZES AND SCATTERED
SHOWERS ACROSS LEEWARD AND INTERIOR SECTIONS...ESPECIALLY OVER THE
WESTERN END OF THE STATE. TRADE WINDS WILL REBUILD ON WEDNESDAY...
LIKELY RETURNING THE FOCUS FOR RAINFALL TO WINDWARD SLOPES.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
MODERATE EASTERLY TRADE WINDS WILL GRADUALLY SHIFT OUT OF THE EAST-
SOUTHEAST ACROSS THE SMALLER ISLANDS TONIGHT AS A DEVELOPING TROUGH
NEARS. A SPRAWLING SURFACE HIGH LOCATED ABOUT 800 MILES NORTH OF
THE STATE IS DRIVING THE TRADES. MEANWHILE...AN ACTIVE SUBTROPICAL
JET STREAM ALOFT RUNNING NORTH OF THE STATE CONTAINS A SHORTWAVE
TROUGH ABOUT 700 MILES NORTHWEST OF KAUAI. THIS FEATURE IS ALREADY
INDUCING A SURFACE TROUGH ALONG AN OLD FRONTAL BOUNDARY 250 TO 300
MILES NORTHWEST OF KAUAI...AND AS THE SHORTWAVE APPROACHES
TONIGHT...THE SURFACE TROUGH WILL ADVANCE CLOSER...CAUSING THE TRADE
WINDS TO WEAKEN AND SHIFT OUT OF THE EAST-SOUTHEAST ACROSS THE
SMALLER ISLANDS. SHOWERS WILL STILL FAVOR WINDWARD SLOPES THROUGH
MUCH OF THE NIGHT...AND WE WILL HAVE TO CLOSELY MONITOR FOR THE
POTENTIAL PLUME MOISTURE TRIGGERING SOME ACTIVE SHOWERS ACROSS
WINDWARD OAHU AS THE LOW LEVEL INVERSION ERODES FROM ITS CURRENT
8000 FT.

A ROUND OF AFTERNOON SEA BREEZES WITH LEEWARD SHOWERS IS EXPECTED ON
TUESDAY. THE SHORTWAVE ALOFT WILL PASS OVERHEAD...DRAGGING ITS
ASSOCIATED WEAK SURFACE TROUGH NEAR KAUAI AND OAHU AND DISRUPTING
THE TRADE WINDS. AS A RESULT...DAYTIME SEA BREEZES WILL BE SOMEWHAT
WIDESPREAD ON THE SMALLER ISLANDS...ESPECIALLY FOR KAUAI AND OAHU...
LEADING TO AFTERNOON SHOWERS OVER LEEWARD AND INTERIOR SECTIONS. THE
SHORTWAVE WILL SIGNIFICANTLY ERODE THE INVERSION...AND PRECIPITABLE
WATER /PW/ VALUES SHOULD JUMP UP AROUND 25 PERCENT FROM THE CURRENT
SEASONABLE VALUES AROUND 1.1 INCHES. UNDER THESE CONDITIONS...A
BRIEF HAVE DOWNPOUR IS POSSIBLE...BUT WIDESPREAD HEAVY SHOWERS ARE
NOT EXPECTED. EXPECT THE BIG ISLAND TO REMAIN UNDER A MODERATE TRADE
WIND FLOW.

A RATHER TYPICAL TRADE WIND WEATHER PATTERN WILL RETURN TUESDAY
NIGHT AND WEDNESDAY AS THE SHORTWAVE LIFTS OUT TO THE NORTHEAST.
MODERATE EASTERLY TRADE WINDS WILL FILL BACK IN AS THE WEAK SURFACE
TROUGH WASHES OUT...FOCUSING SHOWERS BACK ON WINDWARD SLOPES.

.LONG TERM /THURSDAY THROUGH MONDAY/...
A CONTINUED MODERATE...EASTERLY TRADE WIND FLOW IS DEPICTED IN THE
FORECAST FOR THURSDAY ONWARD...THOUGH UNCERTAINTY IS SOMEWHAT HIGH.
FORECAST MODELS ARE SHOWING DIFFERENCES IN THE EVOLUTION OF THE JET
STREAM...WITH THE GFS PUSHING ANOTHER UPPER LEVEL TROUGH A COUPLE
HUNDRED MILES CLOSER TO THE ISLANDS THAN THE ECMWF AND CANADIAN
MODELS FOR THURSDAY THROUGH FRIDAY. THE GFS SOLUTION WOULD SUGGEST
ANOTHER ROUND OF DISRUPTED TRADES...WHILE THE ECMWF AND CANADIAN
MODELS WOULD TEND TO MAINTAIN MORE STABLE EASTERLY TRADE WINDS.
OVERALL...THE ECMWF IS BEING FAVORED BY NCEP...AND WE HAVE OPTED TO
GO WITH THAT FORECAST. ANOTHER FEATURE TO WATCH IS A POSSIBLE
INCREASE IN LOW LEVEL MOISTURE MOVING IN FROM THE SOUTHEAST THIS
WEEKEND.

&&

.AVIATION...
A TROUGH OF LOW PRESSURE WILL DEVELOP NORTH OF THE STATE TONIGHT
AND TUESDAY...ALLOWING THE TRADE WINDS TO DIMINISH ACROSS THE AREA.
CLOUDS AND SHRA WILL REMAIN FOCUSED ACROSS WINDWARD AND MAUKA AREAS
THROUGH TONIGHT WITH INTERIOR SHOWERS POSSIBLE TUESDAY.
PREDOMINANTLY VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH
01/00Z...ALTHOUGH BRIEF MVFR CIGS WILL PERIODICALLY AFFECT PHLI
THROUGH THE NIGHT.

AIRMET SIERRA REMAINS IN EFFECT FOR MTN OBSC ACROSS ALL ISLANDS
WITH THE EXCEPTION OF LANAI AND BIG ISLAND. MTN OBSC WILL LIKELY
REMAIN A PROBLEM ACROSS THE CENTRAL AND NORTHERN ISLANDS THROUGH
THE OVERNIGHT HOURS.

AIRMET TANGO REMAINS IN EFFECT FOR LOW LEVEL TURB THROUGH EARLY THIS
EVENING. TURB SHOULD DECREASE SUFFICIENTLY FOR THE AIRMET TO BE
CANCELLED BY 04Z.

&&

.MARINE...
LOCAL OBSERVATIONS AND AN EARLIER ASCAT PASS SUPPORTED A SMALL CRAFT
ADVISORY /SCA/ FOR THE ALENUIHAHA CHANNEL AND NEAR SOUTH POINT. HIGH
RESOLUTION WRF MODELS SHOW THESE STRONGER WINDS HANGING ON IN THESE
AREAS INTO TONIGHT...SO THE SCA HAS BEEN EXTENDED. THE SCA HAS BEEN
DROPPED FOR THE PAILOLO CHANNEL AND MAALAEA BAY SINCE TRADES WILL BE
VEERING OUT OF THE EAST-SOUTHEAST AND LIKELY NOT AFFECTING THOSE
AREAS TONIGHT. AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...
SCA CONDITIONS WILL LIKELY RETURN TO THE TYPICALLY WINDY WATERS ON
WEDNESDAY...FOLLOWED BY SOME WEAKENING AND VEERING OF THE WINDS
LATER IN THE WEEK.

NO LARGER SWELLS ARE DUE THIS WEEK. A DECLINING NORTHWEST SWELL HAS
RUNNING AROUND 4 TO 5 FT AT 14 SECONDS TODAY. THIS SWELL WILL DROP
ON TUESDAY AND FADE ON WEDNESDAY. A SMALL TO MODERATE SOUTH-
SOUTHEAST SWELL WILL ALSO BE ON A GRADUAL DECLINE OVER THE NEXT
COUPLE OF DAYS...FOLLOWED BY A SMALL SOUTH-SOUTHWEST SWELL FOR THE
SECOND HALF OF THE WORK WEEK. ELEVATED WIND SWELL ALONG EAST FACING
SHORES WILL DROP A NOTCH ON TUESDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST TUESDAY FOR THE ALENUIHAHA
CHANNEL AND BIG ISLAND LEEWARD WATERS.

&&

$$

SHORT TERM LONG TERM AND MARINE...WROE
AVIATION...JELSEMA






000
FXHW60 PHFO 302007
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST MON MAR 30 2015

.SYNOPSIS...
A SOMEWHAT WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH
PORTIONS OF THE UPCOMING WEEK. WHILE THE TRADE WINDS WILL FOCUS
SHOWERS OVER WINDWARD SLOPES AND COASTS...LEEWARD AREAS WILL SEE A
FEW SHOWERS AS WELL. LIGHTER WINDS WILL ALLOW SEABREEZES TO DEVELOP
ON TUESDAY...WITH SCATTERED SHOWERS POSSIBLE ACROSS INTERIOR AND
LEEWARD SECTIONS.

&&

.SHORT TERM /TODAY THROUGH WEDNESDAY NIGHT/...
MODERATE EASTERLY TRADE WINDS WILL CONTINUE TO PRODUCE A SOMEWHAT
ACTIVE RAINFALL PATTERN TODAY...MAINLY ACROSS WINDWARD SLOPES. A
1032 MB SURFACE HIGH PASSING ABOUT 850 MILES NORTH OF THE STATE
WILL KEEP TRADE WINDS BLOWING AT CURRENT STRENGTH THROUGH MUCH OF
THE DAY. OVERALL...THE ATMOSPHERE WILL REMAIN RATHER STABLE WITH
THE INVERSION NEAR 8000 FT...THOUGH MID TO UPPER LEVEL RIDGING WILL
BE ERODING LATER TODAY. PRECIPITABLE WATER /PW/ VALUES ARE RUNNING
AROUND 1.1 INCHES ACCORDING TO THE OVERNIGHT SOUNDINGS...WHICH IS
RIGHT AT SEASONAL NORMALS. IN SPITE OF THESE UNREMARKABLE PW
VALUES...RAINFALL ALONG WINDWARD SLOPES HAS BEEN A BIT ACTIVE
OVERNIGHT AND WILL CONTINUE TO BE SO THROUGH THE DAY. LEEWARD AREAS
WILL CONTINUE TO EXPERIENCE A FEW SHOWERS.

TRADE WINDS WILL GRADUALLY SHIFT OUT OF THE EAST-SOUTHEAST TONIGHT
AND BECOME DISRUPTED OVER THE WESTERN END OF THE STATE ON TUESDAY. A
SHORTWAVE TROUGH ALOFT...CURRENTLY 1000 MILES NORTHWEST OF KAUAI...
WILL APPROACH TONIGHT AND PASS OVERHEAD ON TUESDAY. THIS FEATURE
SHOULD BE STRONG ENOUGH TO INDUCE A WEAK SURFACE TROUGH OVER THE
WESTERN END OF THE STATE AND SIGNIFICANTLY ERODE THE INVERSION. AS
THIS PROCESS DEVELOPS...WE COULD SEE SOME ENHANCEMENT TO WINDWARD
OAHU RAINFALL LATE TONIGHT IF A PLUME SETS UP OFF OF MOLOKAI. THERE
IS HIGHER CONFIDENCE THAT THE SMALLER ISLANDS WILL EXPERIENCE
DAYTIME SEAS BREEZES WITH SOME AFTERNOON LEEWARD SHOWERS...SOME
LOCALLY HEAVY ON KAUAI AND OAHU. EXPECT THE BIG ISLAND TO REMAIN
UNDER A MODERATE TRADE WIND FLOW.

A RATHER TYPICAL...MODERATE TRADE WIND WEATHER PATTERN WILL RETURN
ON WEDNESDAY AS THE SHORTWAVE LIFTS OUT TO THE NORTHEAST. MODERATE
EASTERLY TRADE WINDS WILL FILL BACK IN AS THE WEAK SURFACE TROUGH
WASHES OUT...KEEPING SHOWERS FOCUSED ON WINDWARD SLOPES.

.LONG TERM /THURSDAY THROUGH SUNDAY/...
FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
HIGH PRESSURE NORTH OF THE STATE WILL KEEP A BREEZY TRADE WIND FLOW
IN PLACE ACROSS THE ISLANDS...WITH CLOUDS AND SHRA FOCUSED ACROSS
WINDWARD AND MAUKA AREAS. PREDOMINANTLY VFR CONDITIONS ARE EXPECTED
AT ALL TERMINALS THROUGH 31/18Z...ALTHOUGH BRIEF MVFR CIGS CAN/T BE
RULED OUT AT PHTO AND PHLI.

AIRMET SIERRA REMAINS IN EFFECT FOR MTN OBSC ACROSS ALL ISLANDS
WITH THE EXCEPTION OF LANAI. CONDITIONS SHOULD IMPROVE IN MOST AREAS
LATER THIS MORNING...AND WILL UPDATE THE AIRMETS WHEN THIS OCCURS.

AIRMET TANGO REMAINS IN EFFECT FOR LOW LEVEL TURB...WITH CONDITIONS
EXPECTED TO CONTINUE THROUGH THE DAY.

&&

.MARINE...
A SMALL CRAFT ADVISORY /SCA/ REMAINS POSTED FOR THE TYPICALLY WINDY
WATERS AROUND THE BIG ISLAND AND MAUI THROUGH THE AFTERNOON.
ACCORDING TO LOCAL BUOYS...THE PRESSURE GRADIENT IS BEGINNING TO
RELAX OVER THE ISLANDS...AND THE SCA WILL LIKELY BE DROPPED
TONIGHT. AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...SCA
CONDITIONS WILL LIKELY RETURN TO THE TYPICALLY WINDY WATERS ON
WEDNESDAY...FOLLOWED BY SOME WEAKENING AND VEERING OF THE WINDS
LATER IN THE WEEK.

NO LARGER SWELLS ARE DUE THIS WEEK. A DECLINING NORTHWEST SWELL IS
RUNNING AROUND 4 TO 5 FT AT 12 SECONDS THIS MORNING. THIS SWELL WILL
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

$$

SHORT TERM AND MARINE...WROE
LONG TERM...JACOBSON
AVIATION...JELSEMA






000
FXHW60 PHFO 302007
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST MON MAR 30 2015

.SYNOPSIS...
A SOMEWHAT WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH
PORTIONS OF THE UPCOMING WEEK. WHILE THE TRADE WINDS WILL FOCUS
SHOWERS OVER WINDWARD SLOPES AND COASTS...LEEWARD AREAS WILL SEE A
FEW SHOWERS AS WELL. LIGHTER WINDS WILL ALLOW SEABREEZES TO DEVELOP
ON TUESDAY...WITH SCATTERED SHOWERS POSSIBLE ACROSS INTERIOR AND
LEEWARD SECTIONS.

&&

.SHORT TERM /TODAY THROUGH WEDNESDAY NIGHT/...
MODERATE EASTERLY TRADE WINDS WILL CONTINUE TO PRODUCE A SOMEWHAT
ACTIVE RAINFALL PATTERN TODAY...MAINLY ACROSS WINDWARD SLOPES. A
1032 MB SURFACE HIGH PASSING ABOUT 850 MILES NORTH OF THE STATE
WILL KEEP TRADE WINDS BLOWING AT CURRENT STRENGTH THROUGH MUCH OF
THE DAY. OVERALL...THE ATMOSPHERE WILL REMAIN RATHER STABLE WITH
THE INVERSION NEAR 8000 FT...THOUGH MID TO UPPER LEVEL RIDGING WILL
BE ERODING LATER TODAY. PRECIPITABLE WATER /PW/ VALUES ARE RUNNING
AROUND 1.1 INCHES ACCORDING TO THE OVERNIGHT SOUNDINGS...WHICH IS
RIGHT AT SEASONAL NORMALS. IN SPITE OF THESE UNREMARKABLE PW
VALUES...RAINFALL ALONG WINDWARD SLOPES HAS BEEN A BIT ACTIVE
OVERNIGHT AND WILL CONTINUE TO BE SO THROUGH THE DAY. LEEWARD AREAS
WILL CONTINUE TO EXPERIENCE A FEW SHOWERS.

TRADE WINDS WILL GRADUALLY SHIFT OUT OF THE EAST-SOUTHEAST TONIGHT
AND BECOME DISRUPTED OVER THE WESTERN END OF THE STATE ON TUESDAY. A
SHORTWAVE TROUGH ALOFT...CURRENTLY 1000 MILES NORTHWEST OF KAUAI...
WILL APPROACH TONIGHT AND PASS OVERHEAD ON TUESDAY. THIS FEATURE
SHOULD BE STRONG ENOUGH TO INDUCE A WEAK SURFACE TROUGH OVER THE
WESTERN END OF THE STATE AND SIGNIFICANTLY ERODE THE INVERSION. AS
THIS PROCESS DEVELOPS...WE COULD SEE SOME ENHANCEMENT TO WINDWARD
OAHU RAINFALL LATE TONIGHT IF A PLUME SETS UP OFF OF MOLOKAI. THERE
IS HIGHER CONFIDENCE THAT THE SMALLER ISLANDS WILL EXPERIENCE
DAYTIME SEAS BREEZES WITH SOME AFTERNOON LEEWARD SHOWERS...SOME
LOCALLY HEAVY ON KAUAI AND OAHU. EXPECT THE BIG ISLAND TO REMAIN
UNDER A MODERATE TRADE WIND FLOW.

A RATHER TYPICAL...MODERATE TRADE WIND WEATHER PATTERN WILL RETURN
ON WEDNESDAY AS THE SHORTWAVE LIFTS OUT TO THE NORTHEAST. MODERATE
EASTERLY TRADE WINDS WILL FILL BACK IN AS THE WEAK SURFACE TROUGH
WASHES OUT...KEEPING SHOWERS FOCUSED ON WINDWARD SLOPES.

.LONG TERM /THURSDAY THROUGH SUNDAY/...
FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
HIGH PRESSURE NORTH OF THE STATE WILL KEEP A BREEZY TRADE WIND FLOW
IN PLACE ACROSS THE ISLANDS...WITH CLOUDS AND SHRA FOCUSED ACROSS
WINDWARD AND MAUKA AREAS. PREDOMINANTLY VFR CONDITIONS ARE EXPECTED
AT ALL TERMINALS THROUGH 31/18Z...ALTHOUGH BRIEF MVFR CIGS CAN/T BE
RULED OUT AT PHTO AND PHLI.

AIRMET SIERRA REMAINS IN EFFECT FOR MTN OBSC ACROSS ALL ISLANDS
WITH THE EXCEPTION OF LANAI. CONDITIONS SHOULD IMPROVE IN MOST AREAS
LATER THIS MORNING...AND WILL UPDATE THE AIRMETS WHEN THIS OCCURS.

AIRMET TANGO REMAINS IN EFFECT FOR LOW LEVEL TURB...WITH CONDITIONS
EXPECTED TO CONTINUE THROUGH THE DAY.

&&

.MARINE...
A SMALL CRAFT ADVISORY /SCA/ REMAINS POSTED FOR THE TYPICALLY WINDY
WATERS AROUND THE BIG ISLAND AND MAUI THROUGH THE AFTERNOON.
ACCORDING TO LOCAL BUOYS...THE PRESSURE GRADIENT IS BEGINNING TO
RELAX OVER THE ISLANDS...AND THE SCA WILL LIKELY BE DROPPED
TONIGHT. AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...SCA
CONDITIONS WILL LIKELY RETURN TO THE TYPICALLY WINDY WATERS ON
WEDNESDAY...FOLLOWED BY SOME WEAKENING AND VEERING OF THE WINDS
LATER IN THE WEEK.

NO LARGER SWELLS ARE DUE THIS WEEK. A DECLINING NORTHWEST SWELL IS
RUNNING AROUND 4 TO 5 FT AT 12 SECONDS THIS MORNING. THIS SWELL WILL
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

$$

SHORT TERM AND MARINE...WROE
LONG TERM...JACOBSON
AVIATION...JELSEMA







000
FXHW60 PHFO 302007
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST MON MAR 30 2015

.SYNOPSIS...
A SOMEWHAT WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH
PORTIONS OF THE UPCOMING WEEK. WHILE THE TRADE WINDS WILL FOCUS
SHOWERS OVER WINDWARD SLOPES AND COASTS...LEEWARD AREAS WILL SEE A
FEW SHOWERS AS WELL. LIGHTER WINDS WILL ALLOW SEABREEZES TO DEVELOP
ON TUESDAY...WITH SCATTERED SHOWERS POSSIBLE ACROSS INTERIOR AND
LEEWARD SECTIONS.

&&

.SHORT TERM /TODAY THROUGH WEDNESDAY NIGHT/...
MODERATE EASTERLY TRADE WINDS WILL CONTINUE TO PRODUCE A SOMEWHAT
ACTIVE RAINFALL PATTERN TODAY...MAINLY ACROSS WINDWARD SLOPES. A
1032 MB SURFACE HIGH PASSING ABOUT 850 MILES NORTH OF THE STATE
WILL KEEP TRADE WINDS BLOWING AT CURRENT STRENGTH THROUGH MUCH OF
THE DAY. OVERALL...THE ATMOSPHERE WILL REMAIN RATHER STABLE WITH
THE INVERSION NEAR 8000 FT...THOUGH MID TO UPPER LEVEL RIDGING WILL
BE ERODING LATER TODAY. PRECIPITABLE WATER /PW/ VALUES ARE RUNNING
AROUND 1.1 INCHES ACCORDING TO THE OVERNIGHT SOUNDINGS...WHICH IS
RIGHT AT SEASONAL NORMALS. IN SPITE OF THESE UNREMARKABLE PW
VALUES...RAINFALL ALONG WINDWARD SLOPES HAS BEEN A BIT ACTIVE
OVERNIGHT AND WILL CONTINUE TO BE SO THROUGH THE DAY. LEEWARD AREAS
WILL CONTINUE TO EXPERIENCE A FEW SHOWERS.

TRADE WINDS WILL GRADUALLY SHIFT OUT OF THE EAST-SOUTHEAST TONIGHT
AND BECOME DISRUPTED OVER THE WESTERN END OF THE STATE ON TUESDAY. A
SHORTWAVE TROUGH ALOFT...CURRENTLY 1000 MILES NORTHWEST OF KAUAI...
WILL APPROACH TONIGHT AND PASS OVERHEAD ON TUESDAY. THIS FEATURE
SHOULD BE STRONG ENOUGH TO INDUCE A WEAK SURFACE TROUGH OVER THE
WESTERN END OF THE STATE AND SIGNIFICANTLY ERODE THE INVERSION. AS
THIS PROCESS DEVELOPS...WE COULD SEE SOME ENHANCEMENT TO WINDWARD
OAHU RAINFALL LATE TONIGHT IF A PLUME SETS UP OFF OF MOLOKAI. THERE
IS HIGHER CONFIDENCE THAT THE SMALLER ISLANDS WILL EXPERIENCE
DAYTIME SEAS BREEZES WITH SOME AFTERNOON LEEWARD SHOWERS...SOME
LOCALLY HEAVY ON KAUAI AND OAHU. EXPECT THE BIG ISLAND TO REMAIN
UNDER A MODERATE TRADE WIND FLOW.

A RATHER TYPICAL...MODERATE TRADE WIND WEATHER PATTERN WILL RETURN
ON WEDNESDAY AS THE SHORTWAVE LIFTS OUT TO THE NORTHEAST. MODERATE
EASTERLY TRADE WINDS WILL FILL BACK IN AS THE WEAK SURFACE TROUGH
WASHES OUT...KEEPING SHOWERS FOCUSED ON WINDWARD SLOPES.

.LONG TERM /THURSDAY THROUGH SUNDAY/...
FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
HIGH PRESSURE NORTH OF THE STATE WILL KEEP A BREEZY TRADE WIND FLOW
IN PLACE ACROSS THE ISLANDS...WITH CLOUDS AND SHRA FOCUSED ACROSS
WINDWARD AND MAUKA AREAS. PREDOMINANTLY VFR CONDITIONS ARE EXPECTED
AT ALL TERMINALS THROUGH 31/18Z...ALTHOUGH BRIEF MVFR CIGS CAN/T BE
RULED OUT AT PHTO AND PHLI.

AIRMET SIERRA REMAINS IN EFFECT FOR MTN OBSC ACROSS ALL ISLANDS
WITH THE EXCEPTION OF LANAI. CONDITIONS SHOULD IMPROVE IN MOST AREAS
LATER THIS MORNING...AND WILL UPDATE THE AIRMETS WHEN THIS OCCURS.

AIRMET TANGO REMAINS IN EFFECT FOR LOW LEVEL TURB...WITH CONDITIONS
EXPECTED TO CONTINUE THROUGH THE DAY.

&&

.MARINE...
A SMALL CRAFT ADVISORY /SCA/ REMAINS POSTED FOR THE TYPICALLY WINDY
WATERS AROUND THE BIG ISLAND AND MAUI THROUGH THE AFTERNOON.
ACCORDING TO LOCAL BUOYS...THE PRESSURE GRADIENT IS BEGINNING TO
RELAX OVER THE ISLANDS...AND THE SCA WILL LIKELY BE DROPPED
TONIGHT. AFTER A BRIEF DISRUPTION OF THE TRADES ON TUESDAY...SCA
CONDITIONS WILL LIKELY RETURN TO THE TYPICALLY WINDY WATERS ON
WEDNESDAY...FOLLOWED BY SOME WEAKENING AND VEERING OF THE WINDS
LATER IN THE WEEK.

NO LARGER SWELLS ARE DUE THIS WEEK. A DECLINING NORTHWEST SWELL IS
RUNNING AROUND 4 TO 5 FT AT 12 SECONDS THIS MORNING. THIS SWELL WILL
FADE BY WEDNESDAY. A SMALL TO MODERATE SOUTH-SOUTHEAST SWELL WILL
ALSO BE ON A GRADUAL DECLINE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

$$

SHORT TERM AND MARINE...WROE
LONG TERM...JACOBSON
AVIATION...JELSEMA







000
FXHW60 PHFO 301334
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
334 AM HST MON MAR 30 2015

.SYNOPSIS...
A FAIRLY WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH MOST
OF THE UPCOMING WEEK. WHILE THE TRADE WINDS WILL FOCUS SHOWERS
OVER WINDWARD SLOPES AND COASTS...LEEWARD AREAS WILL SEE A FEW
SHOWERS AS WELL. LIGHTER WINDS WILL ALLOW SEABREEZES TO DEVELOP
IN SOME AREAS ON TUESDAY...WITH SCATTERED SHOWERS POSSIBLE ACROSS
INTERIOR AND LEEWARD SECTIONS.

&&

.DISCUSSION...
FREQUENT SHOWERS HAVE CONTINUED TO STREAM ACROSS MAINLY WINDWARD
SECTIONS OF THE STATE DURING THE NIGHT. RAINFALL AMOUNTS HAVE BEEN
GENERALLY LIGHT...WITH MOST WINDWARD GAUGES RECORDING LESS THAN A
QUARTER INCH DURING THE PAST SIX HOURS. SURFACE ANALYSIS DEPICTS A
1031 MB HIGH ABOUT 800 MILES NORTH OF KAUAI. MODERATE TO FRESH
TRADES PREVAIL OVER THE STATE TO THE SOUTH OF THIS HIGH. ALOFT...
A FLAT RIDGE AXIS IS BEING GRADUALLY SUPPRESSED SOUTH OF THE
STATE...AS A SHORTWAVE TROUGH PUSHES EASTWARD FROM THE DATELINE
ALONG 30N. THE 12Z SOUNDINGS SHOW SLIGHTLY WEAKENED INVERSIONS
BASED AROUND 8000 FEET...WITH NEAR NORMAL PWATS JUST OVER ONE
INCH. MIMIC-TPW SATELLITE IMAGERY INDICATES A SLIGHTLY DRIER AIRMASS
JUST TO THE EAST OF THE STATE...WITH ESTIMATED PWATS IN THAT AREA
SLIGHTLY BELOW ONE INCH.

MODERATE TO FRESH TRADES WILL CONTINUE ACROSS THE STATE TODAY...
AS THE SFC HIGH PASSES BY TO OUR NORTH. HEIGHTS WILL BEGIN TO FALL
ALOFT...AS A MID/UPPER LEVEL TROUGH PUSHES EASTWARD FROM THE
DATELINE OVER THE NW HAWAIIAN ISLANDS. THIS WILL ALLOW FOR THE
INVERSION TO RISE AND WEAKEN FURTHER...CONTINUING THE PROCESS
WHICH APPEARS TO HAVE ALREADY BEGUN DURING THE NIGHT. THIS SHOULD
KEEP TRADE WIND SHOWERS FAIRLY ACTIVE EVEN DURING THE AFTERNOON
HOURS...ALTHOUGH THE SLIGHTLY DRIER AIRMASS MOVING IN FROM THE
EAST MAY REDUCE SHOWER COVERAGE SOMEWHAT.

TRADES ARE EXPECTED TO WEAKEN TONIGHT AND TUESDAY...AS THE
MID/UPPER TROUGH PASSES NORTH OF THE STATE...AND A WEAK SFC TROUGH
DEVELOPS IN RESPONSE NEAR AND NORTH OF THE ISLANDS. MODELS
INDICATE THAT THE INVERSION WILL WEAKEN AND RISE A BIT FURTHER
DURING THIS TIME...WITH SOME MODEST INCREASE OF LOW LEVEL MOISTURE
AS WELL. THE TRADES MAY WEAKEN ENOUGH TO ALLOW SEABREEZES TO
DEVELOP ACROSS MANY AREAS ON TUESDAY AFTERNOON. INCREASED
MOISTURE/INSTABILITY COULD GENERATE A FEW HEAVIER DOWNPOURS MONDAY
NIGHT AND TUESDAY...POTENTIALLY ALSO ENHANCED BY SEABREEZE
CONVERGENCE TUESDAY AFTERNOON.

TRADE WINDS SHOULD INCREASE OVER THE ISLANDS ONCE AGAIN ON
WEDNESDAY AS THE MID LEVEL DISTURBANCE MOVES AWAY TO OUR NE AND
THE NEARBY LOW LEVEL TROUGH WASHES OUT. A SHORTWAVE MID LEVEL
RIDGE PASSING OVERHEAD SHOULD STRENGTHEN AND LOWER THE INVERSION
ONCE AGAIN AS WELL...THUS WOULD EXPECT TYPICAL TRADE WIND WEATHER
WITH MOSTLY LIGHT SHOWERS FOCUSING WINDWARD AND MAUKA.

FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
CLOUDS AND SHOWERS WILL REMAIN FOCUSED OVER WINDWARD SECTIONS OF
THE STATE TODAY...AS MODERATE TO FRESH TRADE WINDS PREVAIL. AIRMET
SIERRA FOR MOUNTAIN OBSCURATION REMAINS IN EFFECT FOR WINDWARD
SECTIONS OF ALL ISLANDS.

VFR CONDITIONS WILL PREVAIL ELSEWHERE...WITH JUST ISOLATED MVFR
CEILINGS POSSIBLE AT TIMES MAINLY IN -SHRA.

AIRMET TANGO FOR MODERATE LOW LEVEL TURBULENCE IS IN EFFECT
OVER AND S THRU W OF THE MOUNTAINS DUE TO THE TRADE WINDS.

&&

.MARINE...
NW SWELL PEAKED AROUND MIDDAY SUNDAY AT BUOY 51101...AND APPEARS
TO HAVE PEAKED DURING THE NIGHT AT THE NEARSHORE CDIP BUOYS OFF
KAUAI AND OAHU. THIS SWELL AND RESULTING SURF WILL CONTINUE
TO GRADUALLY SUBSIDE TODAY THROUGH TUESDAY...AND THE HIGH SURF
ADVISORY FOR NORTH AND WEST FACING SHORES HAS BEEN DROPPED.

OTHERWISE...SMALL SOUTH SWELL WILL CONTINUE PRODUCING SMALL SURF
ON SOUTH FACING SHORES THROUGH MID WEEK. A SMALL WNW SWELL MAY
ARRIVE INTO THE ISLANDS NEXT WEEKEND.

THE SUNDAY EVENING ASCAT PASS MISSED THE HAWAIIAN COASTAL WATERS...
BUT AVAILABLE MESONET DATA AND HIGH-RESOLUTION WRF MODEL OUTPUT
SUGGEST THAT SMALL CRAFT ADVISORY WINDS OF 25 KT ARE CONTINUING
IN THE TYPICALLY WINDY WATERS AROUND THE BIG ISLAND AND MAUI
COUNTY. THE ADVISORY REMAINS POSTED FOR THOSE AREAS THROUGH
TODAY. MODELS SUGGEST THAT 25 KT WINDS MAY PERSIST ACROSS SOME
WATERS INTO TONIGHT...BUT WILL LET THE DAY SHIFT MONITOR LATER
TRENDS AND HOPEFULLY SEE AN ASCAT PASS BEFORE DECIDING WHETHER TO
EXTEND THE SCA BEYOND 6 PM.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

$$

JACOBSON









000
FXHW60 PHFO 301334
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
334 AM HST MON MAR 30 2015

.SYNOPSIS...
A FAIRLY WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH MOST
OF THE UPCOMING WEEK. WHILE THE TRADE WINDS WILL FOCUS SHOWERS
OVER WINDWARD SLOPES AND COASTS...LEEWARD AREAS WILL SEE A FEW
SHOWERS AS WELL. LIGHTER WINDS WILL ALLOW SEABREEZES TO DEVELOP
IN SOME AREAS ON TUESDAY...WITH SCATTERED SHOWERS POSSIBLE ACROSS
INTERIOR AND LEEWARD SECTIONS.

&&

.DISCUSSION...
FREQUENT SHOWERS HAVE CONTINUED TO STREAM ACROSS MAINLY WINDWARD
SECTIONS OF THE STATE DURING THE NIGHT. RAINFALL AMOUNTS HAVE BEEN
GENERALLY LIGHT...WITH MOST WINDWARD GAUGES RECORDING LESS THAN A
QUARTER INCH DURING THE PAST SIX HOURS. SURFACE ANALYSIS DEPICTS A
1031 MB HIGH ABOUT 800 MILES NORTH OF KAUAI. MODERATE TO FRESH
TRADES PREVAIL OVER THE STATE TO THE SOUTH OF THIS HIGH. ALOFT...
A FLAT RIDGE AXIS IS BEING GRADUALLY SUPPRESSED SOUTH OF THE
STATE...AS A SHORTWAVE TROUGH PUSHES EASTWARD FROM THE DATELINE
ALONG 30N. THE 12Z SOUNDINGS SHOW SLIGHTLY WEAKENED INVERSIONS
BASED AROUND 8000 FEET...WITH NEAR NORMAL PWATS JUST OVER ONE
INCH. MIMIC-TPW SATELLITE IMAGERY INDICATES A SLIGHTLY DRIER AIRMASS
JUST TO THE EAST OF THE STATE...WITH ESTIMATED PWATS IN THAT AREA
SLIGHTLY BELOW ONE INCH.

MODERATE TO FRESH TRADES WILL CONTINUE ACROSS THE STATE TODAY...
AS THE SFC HIGH PASSES BY TO OUR NORTH. HEIGHTS WILL BEGIN TO FALL
ALOFT...AS A MID/UPPER LEVEL TROUGH PUSHES EASTWARD FROM THE
DATELINE OVER THE NW HAWAIIAN ISLANDS. THIS WILL ALLOW FOR THE
INVERSION TO RISE AND WEAKEN FURTHER...CONTINUING THE PROCESS
WHICH APPEARS TO HAVE ALREADY BEGUN DURING THE NIGHT. THIS SHOULD
KEEP TRADE WIND SHOWERS FAIRLY ACTIVE EVEN DURING THE AFTERNOON
HOURS...ALTHOUGH THE SLIGHTLY DRIER AIRMASS MOVING IN FROM THE
EAST MAY REDUCE SHOWER COVERAGE SOMEWHAT.

TRADES ARE EXPECTED TO WEAKEN TONIGHT AND TUESDAY...AS THE
MID/UPPER TROUGH PASSES NORTH OF THE STATE...AND A WEAK SFC TROUGH
DEVELOPS IN RESPONSE NEAR AND NORTH OF THE ISLANDS. MODELS
INDICATE THAT THE INVERSION WILL WEAKEN AND RISE A BIT FURTHER
DURING THIS TIME...WITH SOME MODEST INCREASE OF LOW LEVEL MOISTURE
AS WELL. THE TRADES MAY WEAKEN ENOUGH TO ALLOW SEABREEZES TO
DEVELOP ACROSS MANY AREAS ON TUESDAY AFTERNOON. INCREASED
MOISTURE/INSTABILITY COULD GENERATE A FEW HEAVIER DOWNPOURS MONDAY
NIGHT AND TUESDAY...POTENTIALLY ALSO ENHANCED BY SEABREEZE
CONVERGENCE TUESDAY AFTERNOON.

TRADE WINDS SHOULD INCREASE OVER THE ISLANDS ONCE AGAIN ON
WEDNESDAY AS THE MID LEVEL DISTURBANCE MOVES AWAY TO OUR NE AND
THE NEARBY LOW LEVEL TROUGH WASHES OUT. A SHORTWAVE MID LEVEL
RIDGE PASSING OVERHEAD SHOULD STRENGTHEN AND LOWER THE INVERSION
ONCE AGAIN AS WELL...THUS WOULD EXPECT TYPICAL TRADE WIND WEATHER
WITH MOSTLY LIGHT SHOWERS FOCUSING WINDWARD AND MAUKA.

FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
CLOUDS AND SHOWERS WILL REMAIN FOCUSED OVER WINDWARD SECTIONS OF
THE STATE TODAY...AS MODERATE TO FRESH TRADE WINDS PREVAIL. AIRMET
SIERRA FOR MOUNTAIN OBSCURATION REMAINS IN EFFECT FOR WINDWARD
SECTIONS OF ALL ISLANDS.

VFR CONDITIONS WILL PREVAIL ELSEWHERE...WITH JUST ISOLATED MVFR
CEILINGS POSSIBLE AT TIMES MAINLY IN -SHRA.

AIRMET TANGO FOR MODERATE LOW LEVEL TURBULENCE IS IN EFFECT
OVER AND S THRU W OF THE MOUNTAINS DUE TO THE TRADE WINDS.

&&

.MARINE...
NW SWELL PEAKED AROUND MIDDAY SUNDAY AT BUOY 51101...AND APPEARS
TO HAVE PEAKED DURING THE NIGHT AT THE NEARSHORE CDIP BUOYS OFF
KAUAI AND OAHU. THIS SWELL AND RESULTING SURF WILL CONTINUE
TO GRADUALLY SUBSIDE TODAY THROUGH TUESDAY...AND THE HIGH SURF
ADVISORY FOR NORTH AND WEST FACING SHORES HAS BEEN DROPPED.

OTHERWISE...SMALL SOUTH SWELL WILL CONTINUE PRODUCING SMALL SURF
ON SOUTH FACING SHORES THROUGH MID WEEK. A SMALL WNW SWELL MAY
ARRIVE INTO THE ISLANDS NEXT WEEKEND.

THE SUNDAY EVENING ASCAT PASS MISSED THE HAWAIIAN COASTAL WATERS...
BUT AVAILABLE MESONET DATA AND HIGH-RESOLUTION WRF MODEL OUTPUT
SUGGEST THAT SMALL CRAFT ADVISORY WINDS OF 25 KT ARE CONTINUING
IN THE TYPICALLY WINDY WATERS AROUND THE BIG ISLAND AND MAUI
COUNTY. THE ADVISORY REMAINS POSTED FOR THOSE AREAS THROUGH
TODAY. MODELS SUGGEST THAT 25 KT WINDS MAY PERSIST ACROSS SOME
WATERS INTO TONIGHT...BUT WILL LET THE DAY SHIFT MONITOR LATER
TRENDS AND HOPEFULLY SEE AN ASCAT PASS BEFORE DECIDING WHETHER TO
EXTEND THE SCA BEYOND 6 PM.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

$$

JACOBSON








000
FXHW60 PHFO 301334
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
334 AM HST MON MAR 30 2015

.SYNOPSIS...
A FAIRLY WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH MOST
OF THE UPCOMING WEEK. WHILE THE TRADE WINDS WILL FOCUS SHOWERS
OVER WINDWARD SLOPES AND COASTS...LEEWARD AREAS WILL SEE A FEW
SHOWERS AS WELL. LIGHTER WINDS WILL ALLOW SEABREEZES TO DEVELOP
IN SOME AREAS ON TUESDAY...WITH SCATTERED SHOWERS POSSIBLE ACROSS
INTERIOR AND LEEWARD SECTIONS.

&&

.DISCUSSION...
FREQUENT SHOWERS HAVE CONTINUED TO STREAM ACROSS MAINLY WINDWARD
SECTIONS OF THE STATE DURING THE NIGHT. RAINFALL AMOUNTS HAVE BEEN
GENERALLY LIGHT...WITH MOST WINDWARD GAUGES RECORDING LESS THAN A
QUARTER INCH DURING THE PAST SIX HOURS. SURFACE ANALYSIS DEPICTS A
1031 MB HIGH ABOUT 800 MILES NORTH OF KAUAI. MODERATE TO FRESH
TRADES PREVAIL OVER THE STATE TO THE SOUTH OF THIS HIGH. ALOFT...
A FLAT RIDGE AXIS IS BEING GRADUALLY SUPPRESSED SOUTH OF THE
STATE...AS A SHORTWAVE TROUGH PUSHES EASTWARD FROM THE DATELINE
ALONG 30N. THE 12Z SOUNDINGS SHOW SLIGHTLY WEAKENED INVERSIONS
BASED AROUND 8000 FEET...WITH NEAR NORMAL PWATS JUST OVER ONE
INCH. MIMIC-TPW SATELLITE IMAGERY INDICATES A SLIGHTLY DRIER AIRMASS
JUST TO THE EAST OF THE STATE...WITH ESTIMATED PWATS IN THAT AREA
SLIGHTLY BELOW ONE INCH.

MODERATE TO FRESH TRADES WILL CONTINUE ACROSS THE STATE TODAY...
AS THE SFC HIGH PASSES BY TO OUR NORTH. HEIGHTS WILL BEGIN TO FALL
ALOFT...AS A MID/UPPER LEVEL TROUGH PUSHES EASTWARD FROM THE
DATELINE OVER THE NW HAWAIIAN ISLANDS. THIS WILL ALLOW FOR THE
INVERSION TO RISE AND WEAKEN FURTHER...CONTINUING THE PROCESS
WHICH APPEARS TO HAVE ALREADY BEGUN DURING THE NIGHT. THIS SHOULD
KEEP TRADE WIND SHOWERS FAIRLY ACTIVE EVEN DURING THE AFTERNOON
HOURS...ALTHOUGH THE SLIGHTLY DRIER AIRMASS MOVING IN FROM THE
EAST MAY REDUCE SHOWER COVERAGE SOMEWHAT.

TRADES ARE EXPECTED TO WEAKEN TONIGHT AND TUESDAY...AS THE
MID/UPPER TROUGH PASSES NORTH OF THE STATE...AND A WEAK SFC TROUGH
DEVELOPS IN RESPONSE NEAR AND NORTH OF THE ISLANDS. MODELS
INDICATE THAT THE INVERSION WILL WEAKEN AND RISE A BIT FURTHER
DURING THIS TIME...WITH SOME MODEST INCREASE OF LOW LEVEL MOISTURE
AS WELL. THE TRADES MAY WEAKEN ENOUGH TO ALLOW SEABREEZES TO
DEVELOP ACROSS MANY AREAS ON TUESDAY AFTERNOON. INCREASED
MOISTURE/INSTABILITY COULD GENERATE A FEW HEAVIER DOWNPOURS MONDAY
NIGHT AND TUESDAY...POTENTIALLY ALSO ENHANCED BY SEABREEZE
CONVERGENCE TUESDAY AFTERNOON.

TRADE WINDS SHOULD INCREASE OVER THE ISLANDS ONCE AGAIN ON
WEDNESDAY AS THE MID LEVEL DISTURBANCE MOVES AWAY TO OUR NE AND
THE NEARBY LOW LEVEL TROUGH WASHES OUT. A SHORTWAVE MID LEVEL
RIDGE PASSING OVERHEAD SHOULD STRENGTHEN AND LOWER THE INVERSION
ONCE AGAIN AS WELL...THUS WOULD EXPECT TYPICAL TRADE WIND WEATHER
WITH MOSTLY LIGHT SHOWERS FOCUSING WINDWARD AND MAUKA.

FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
CLOUDS AND SHOWERS WILL REMAIN FOCUSED OVER WINDWARD SECTIONS OF
THE STATE TODAY...AS MODERATE TO FRESH TRADE WINDS PREVAIL. AIRMET
SIERRA FOR MOUNTAIN OBSCURATION REMAINS IN EFFECT FOR WINDWARD
SECTIONS OF ALL ISLANDS.

VFR CONDITIONS WILL PREVAIL ELSEWHERE...WITH JUST ISOLATED MVFR
CEILINGS POSSIBLE AT TIMES MAINLY IN -SHRA.

AIRMET TANGO FOR MODERATE LOW LEVEL TURBULENCE IS IN EFFECT
OVER AND S THRU W OF THE MOUNTAINS DUE TO THE TRADE WINDS.

&&

.MARINE...
NW SWELL PEAKED AROUND MIDDAY SUNDAY AT BUOY 51101...AND APPEARS
TO HAVE PEAKED DURING THE NIGHT AT THE NEARSHORE CDIP BUOYS OFF
KAUAI AND OAHU. THIS SWELL AND RESULTING SURF WILL CONTINUE
TO GRADUALLY SUBSIDE TODAY THROUGH TUESDAY...AND THE HIGH SURF
ADVISORY FOR NORTH AND WEST FACING SHORES HAS BEEN DROPPED.

OTHERWISE...SMALL SOUTH SWELL WILL CONTINUE PRODUCING SMALL SURF
ON SOUTH FACING SHORES THROUGH MID WEEK. A SMALL WNW SWELL MAY
ARRIVE INTO THE ISLANDS NEXT WEEKEND.

THE SUNDAY EVENING ASCAT PASS MISSED THE HAWAIIAN COASTAL WATERS...
BUT AVAILABLE MESONET DATA AND HIGH-RESOLUTION WRF MODEL OUTPUT
SUGGEST THAT SMALL CRAFT ADVISORY WINDS OF 25 KT ARE CONTINUING
IN THE TYPICALLY WINDY WATERS AROUND THE BIG ISLAND AND MAUI
COUNTY. THE ADVISORY REMAINS POSTED FOR THOSE AREAS THROUGH
TODAY. MODELS SUGGEST THAT 25 KT WINDS MAY PERSIST ACROSS SOME
WATERS INTO TONIGHT...BUT WILL LET THE DAY SHIFT MONITOR LATER
TRENDS AND HOPEFULLY SEE AN ASCAT PASS BEFORE DECIDING WHETHER TO
EXTEND THE SCA BEYOND 6 PM.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

$$

JACOBSON








000
FXHW60 PHFO 301334
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
334 AM HST MON MAR 30 2015

.SYNOPSIS...
A FAIRLY WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH MOST
OF THE UPCOMING WEEK. WHILE THE TRADE WINDS WILL FOCUS SHOWERS
OVER WINDWARD SLOPES AND COASTS...LEEWARD AREAS WILL SEE A FEW
SHOWERS AS WELL. LIGHTER WINDS WILL ALLOW SEABREEZES TO DEVELOP
IN SOME AREAS ON TUESDAY...WITH SCATTERED SHOWERS POSSIBLE ACROSS
INTERIOR AND LEEWARD SECTIONS.

&&

.DISCUSSION...
FREQUENT SHOWERS HAVE CONTINUED TO STREAM ACROSS MAINLY WINDWARD
SECTIONS OF THE STATE DURING THE NIGHT. RAINFALL AMOUNTS HAVE BEEN
GENERALLY LIGHT...WITH MOST WINDWARD GAUGES RECORDING LESS THAN A
QUARTER INCH DURING THE PAST SIX HOURS. SURFACE ANALYSIS DEPICTS A
1031 MB HIGH ABOUT 800 MILES NORTH OF KAUAI. MODERATE TO FRESH
TRADES PREVAIL OVER THE STATE TO THE SOUTH OF THIS HIGH. ALOFT...
A FLAT RIDGE AXIS IS BEING GRADUALLY SUPPRESSED SOUTH OF THE
STATE...AS A SHORTWAVE TROUGH PUSHES EASTWARD FROM THE DATELINE
ALONG 30N. THE 12Z SOUNDINGS SHOW SLIGHTLY WEAKENED INVERSIONS
BASED AROUND 8000 FEET...WITH NEAR NORMAL PWATS JUST OVER ONE
INCH. MIMIC-TPW SATELLITE IMAGERY INDICATES A SLIGHTLY DRIER AIRMASS
JUST TO THE EAST OF THE STATE...WITH ESTIMATED PWATS IN THAT AREA
SLIGHTLY BELOW ONE INCH.

MODERATE TO FRESH TRADES WILL CONTINUE ACROSS THE STATE TODAY...
AS THE SFC HIGH PASSES BY TO OUR NORTH. HEIGHTS WILL BEGIN TO FALL
ALOFT...AS A MID/UPPER LEVEL TROUGH PUSHES EASTWARD FROM THE
DATELINE OVER THE NW HAWAIIAN ISLANDS. THIS WILL ALLOW FOR THE
INVERSION TO RISE AND WEAKEN FURTHER...CONTINUING THE PROCESS
WHICH APPEARS TO HAVE ALREADY BEGUN DURING THE NIGHT. THIS SHOULD
KEEP TRADE WIND SHOWERS FAIRLY ACTIVE EVEN DURING THE AFTERNOON
HOURS...ALTHOUGH THE SLIGHTLY DRIER AIRMASS MOVING IN FROM THE
EAST MAY REDUCE SHOWER COVERAGE SOMEWHAT.

TRADES ARE EXPECTED TO WEAKEN TONIGHT AND TUESDAY...AS THE
MID/UPPER TROUGH PASSES NORTH OF THE STATE...AND A WEAK SFC TROUGH
DEVELOPS IN RESPONSE NEAR AND NORTH OF THE ISLANDS. MODELS
INDICATE THAT THE INVERSION WILL WEAKEN AND RISE A BIT FURTHER
DURING THIS TIME...WITH SOME MODEST INCREASE OF LOW LEVEL MOISTURE
AS WELL. THE TRADES MAY WEAKEN ENOUGH TO ALLOW SEABREEZES TO
DEVELOP ACROSS MANY AREAS ON TUESDAY AFTERNOON. INCREASED
MOISTURE/INSTABILITY COULD GENERATE A FEW HEAVIER DOWNPOURS MONDAY
NIGHT AND TUESDAY...POTENTIALLY ALSO ENHANCED BY SEABREEZE
CONVERGENCE TUESDAY AFTERNOON.

TRADE WINDS SHOULD INCREASE OVER THE ISLANDS ONCE AGAIN ON
WEDNESDAY AS THE MID LEVEL DISTURBANCE MOVES AWAY TO OUR NE AND
THE NEARBY LOW LEVEL TROUGH WASHES OUT. A SHORTWAVE MID LEVEL
RIDGE PASSING OVERHEAD SHOULD STRENGTHEN AND LOWER THE INVERSION
ONCE AGAIN AS WELL...THUS WOULD EXPECT TYPICAL TRADE WIND WEATHER
WITH MOSTLY LIGHT SHOWERS FOCUSING WINDWARD AND MAUKA.

FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
CLOUDS AND SHOWERS WILL REMAIN FOCUSED OVER WINDWARD SECTIONS OF
THE STATE TODAY...AS MODERATE TO FRESH TRADE WINDS PREVAIL. AIRMET
SIERRA FOR MOUNTAIN OBSCURATION REMAINS IN EFFECT FOR WINDWARD
SECTIONS OF ALL ISLANDS.

VFR CONDITIONS WILL PREVAIL ELSEWHERE...WITH JUST ISOLATED MVFR
CEILINGS POSSIBLE AT TIMES MAINLY IN -SHRA.

AIRMET TANGO FOR MODERATE LOW LEVEL TURBULENCE IS IN EFFECT
OVER AND S THRU W OF THE MOUNTAINS DUE TO THE TRADE WINDS.

&&

.MARINE...
NW SWELL PEAKED AROUND MIDDAY SUNDAY AT BUOY 51101...AND APPEARS
TO HAVE PEAKED DURING THE NIGHT AT THE NEARSHORE CDIP BUOYS OFF
KAUAI AND OAHU. THIS SWELL AND RESULTING SURF WILL CONTINUE
TO GRADUALLY SUBSIDE TODAY THROUGH TUESDAY...AND THE HIGH SURF
ADVISORY FOR NORTH AND WEST FACING SHORES HAS BEEN DROPPED.

OTHERWISE...SMALL SOUTH SWELL WILL CONTINUE PRODUCING SMALL SURF
ON SOUTH FACING SHORES THROUGH MID WEEK. A SMALL WNW SWELL MAY
ARRIVE INTO THE ISLANDS NEXT WEEKEND.

THE SUNDAY EVENING ASCAT PASS MISSED THE HAWAIIAN COASTAL WATERS...
BUT AVAILABLE MESONET DATA AND HIGH-RESOLUTION WRF MODEL OUTPUT
SUGGEST THAT SMALL CRAFT ADVISORY WINDS OF 25 KT ARE CONTINUING
IN THE TYPICALLY WINDY WATERS AROUND THE BIG ISLAND AND MAUI
COUNTY. THE ADVISORY REMAINS POSTED FOR THOSE AREAS THROUGH
TODAY. MODELS SUGGEST THAT 25 KT WINDS MAY PERSIST ACROSS SOME
WATERS INTO TONIGHT...BUT WILL LET THE DAY SHIFT MONITOR LATER
TRENDS AND HOPEFULLY SEE AN ASCAT PASS BEFORE DECIDING WHETHER TO
EXTEND THE SCA BEYOND 6 PM.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

$$

JACOBSON









000
FXHW60 PHFO 300624
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
824 PM HST SUN MAR 29 2015

.SYNOPSIS...
A FAIRLY WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH MOST
OF THE UPCOMING WEEK...ALTHOUGH WINDS WILL BE RATHER LIGHT ON
TUESDAY. WHILE THE TRADE WINDS WILL FOCUS SHOWERS OVER WINDWARD
SLOPES AND COASTS...LEEWARD AREAS WILL SEE A FEW SHOWERS AS WELL.

&&

.DISCUSSION...
SCATTERED SHOWERS CONTINUE TO STREAM ACROSS MAINLY WINDWARD
SECTIONS OF THE STATE THIS EVENING. RAINFALL AMOUNTS HAVE BEEN
GENERALLY LIGHT...WITH MOST WINDWARD GAUGES RECORDING LESS THAN A
QUARTER INCH DURING THE PAST SIX HOURS. SURFACE ANALYSIS DEPICTS
A 1032 MB HIGH ABOUT 1000 MILES NW OF PHNL...WITH ANOTHER WEAKER
HIGH ABOUT 1200 MILES NE OF PHNL. A WEAK FRONT BETWEEN THESE TWO
HIGHS IS PASSING WELL NORTH OF THE STATE. MODERATE TO FRESH TRADES
PREVAIL OVER THE ISLANDS. ALOFT...A FLAT RIDGE AXIS IS BEING
GRADUALLY SUPPRESSED SOUTH OF THE STATE...AS A SHORTWAVE TROUGH
PUSHES EASTWARD FROM THE DATELINE ALONG 30N. THE 00Z SOUNDINGS
SHOW WELL-DEFINED INVERSIONS BASED AROUND 7500 FEET...WITH
SOMEWHAT BELOW NORMAL PWATS NEAR ONE INCH. MIMIC-TPW SATELLITE
IMAGERY INDICATES LITTLE VARIATION IN THE AIRMASS AROUND THE
ISLANDS...WITH ESTIMATED PWATS MOSTLY BETWEEN 1.0 AND 1.1 INCHES.

EXPECT LITTLE CHANGE OVERNIGHT...WITH SHOWERS AND CLOUDS
CONTINUING TO FOCUS WINDWARD...AND SOME SHOWERS SPILLING OVER
LEEWARD ON THE SMALLER ISLANDS. THE EXISTING FORECAST IS ON
TRACK...AND NO CHANGES ARE PLANNED FOR THIS EVENING.

MODERATE TO FRESH TRADES WILL CONTINUE ACROSS THE STATE ON
MONDAY...AS THE SFC HIGH PASSES BY TO OUR NORTH. HEIGHTS WILL
BEGIN TO FALL ALOFT...AS A MID/UPPER LEVEL TROUGH PUSHES EASTWARD
FROM THE DATELINE OVER THE NW HAWAIIAN ISLANDS. THIS WILL ALLOW
FOR THE INVERSION TO RISE AND WEAKEN SOMEWHAT...LIKELY KEEPING
TRADE WIND SHOWERS FAIRLY ACTIVE EVEN DURING THE AFTERNOON HOURS.

TRADES ARE EXPECTED TO WEAKEN MONDAY NIGHT AND TUESDAY...AS
THE MID/UPPER TROUGH PASSES NORTH OF THE STATE...AND A WEAK
SFC TROUGH DEVELOPS IN RESPONSE NEAR AND NORTH OF THE ISLANDS.
MODELS INDICATE THAT THE INVERSION WILL WEAKEN AND RISE A BIT
FURTHER DURING THIS TIME...WITH SOME MODEST INCREASE OF LOW LEVEL
MOISTURE AS WELL. THE TRADES MAY WEAKEN ENOUGH TO ALLOW SEABREEZES
TO DEVELOP ACROSS MANY AREAS ON TUESDAY AFTERNOON. INCREASED
MOISTURE/INSTABILITY COULD GENERATE A FEW HEAVIER DOWNPOURS MONDAY
NIGHT AND TUESDAY...POTENTIALLY ALSO ENHANCED BY SEABREEZE
CONVERGENCE TUESDAY AFTERNOON.

TRADE WINDS SHOULD INCREASE OVER THE ISLANDS ONCE AGAIN ON
WEDNESDAY AS THE MID LEVEL DISTURBANCE MOVES AWAY TO OUR NE AND
THE NEARBY LOW LEVEL TROUGH WASHES OUT. A SHORTWAVE MID LEVEL
RIDGE PASSING OVERHEAD SHOULD STRENGTHEN AND LOWER THE INVERSION
ONCE AGAIN AS WELL...THUS WOULD EXPECT TYPICAL TRADE WIND WEATHER
WITH MOSTLY LIGHT SHOWERS FOCUSING WINDWARD AND MAUKA.

FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
CLOUDS AND SHOWERS WILL REMAIN FOCUSED OVER WINDWARD SECTIONS OF
THE STATE THROUGH TONIGHT...AS MODERATE TO FRESH TRADE WINDS
PREVAIL. AIRMET SIERRA FOR MOUNTAIN OBSCURATION REMAINS IN EFFECT
FOR WINDWARD SECTIONS OF KAUAI...OAHU AND MOLOKAI.

VFR CONDITIONS WILL PREVAIL ELSEWHERE...WITH JUST ISOLATED MVFR
CEILINGS POSSIBLE AT TIMES MAINLY IN -SHRA.

AIRMET TANGO FOR MODERATE LOW LEVEL TURBULENCE HAS BEEN POSTED S
AND W OF THE MOUNTAINS DUE TO INCREASING TRADE WINDS.

&&

.MARINE...
NW SWELL APPEARS TO HAVE PEAKED AROUND MIDDAY SUNDAY AT BUOY 51101...
AND IS PROBABLY PEAKING NOW AT THE NEARSHORE CDIP BUOYS. RESULTING
SURF WILL BE NEAR ADVISORY LEVELS ALONG NORTH/WEST FACING SHORES
OF KAUAI...AND NORTH FACING SHORES OF OAHU/MOLOKAI/MAUI OVERNIGHT.
THIS SWELL AND SURF SHOULD BEGIN TO SUBSIDE LATE TONIGHT...AND
CONTINUE DROPPING MONDAY THROUGH TUESDAY.

OTHERWISE...SMALL SOUTH SWELL WILL CONTINUE PRODUCING SMALL SURF
ON SOUTH FACING SHORES THROUGH MID WEEK. A SMALL WNW SWELL MAY
ARRIVE INTO THE ISLANDS NEXT WEEKEND.

THE SUNDAY MORNING ASCAT PASS FOUND WINDS UP TO 25 KT IN THE
ALENUIHAHA CHANNEL...AND A SMALL CRAFT ADVISORY /SCA/ HAS BEEN
POSTED THERE AS WELL AS SOUTH OF THE BIG ISLAND. RECENT MESONET
DATA FROM MAALAEA BAY AND LANAI INDICATE THAT WINDS MAY BE NEAR 25
KT IN MAALAEA AND THE PAILOLO CHANNEL AS WELL. WILL CONSIDER
EXPANDING THE SCA INTO THOSE WATERS WITH THE EVENING FORECAST
UPDATE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 AM HST MONDAY FOR NORTH AND WEST FACING
SHORES OF KAUAI AND NIIHAU AND FOR NORTH FACING SHORES OF OAHU
MOLOKAI AND MAUI.

SMALL CRAFT ADVISORY UNTIL 6 PM HST MONDAY FOR ALENUIHAHA
CHANNEL-BIG ISLAND LEEWARD WATERS-BIG ISLAND SOUTHEAST WATERS.

&&

$$

JACOBSON








000
FXHW60 PHFO 300624
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
824 PM HST SUN MAR 29 2015

.SYNOPSIS...
A FAIRLY WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH MOST
OF THE UPCOMING WEEK...ALTHOUGH WINDS WILL BE RATHER LIGHT ON
TUESDAY. WHILE THE TRADE WINDS WILL FOCUS SHOWERS OVER WINDWARD
SLOPES AND COASTS...LEEWARD AREAS WILL SEE A FEW SHOWERS AS WELL.

&&

.DISCUSSION...
SCATTERED SHOWERS CONTINUE TO STREAM ACROSS MAINLY WINDWARD
SECTIONS OF THE STATE THIS EVENING. RAINFALL AMOUNTS HAVE BEEN
GENERALLY LIGHT...WITH MOST WINDWARD GAUGES RECORDING LESS THAN A
QUARTER INCH DURING THE PAST SIX HOURS. SURFACE ANALYSIS DEPICTS
A 1032 MB HIGH ABOUT 1000 MILES NW OF PHNL...WITH ANOTHER WEAKER
HIGH ABOUT 1200 MILES NE OF PHNL. A WEAK FRONT BETWEEN THESE TWO
HIGHS IS PASSING WELL NORTH OF THE STATE. MODERATE TO FRESH TRADES
PREVAIL OVER THE ISLANDS. ALOFT...A FLAT RIDGE AXIS IS BEING
GRADUALLY SUPPRESSED SOUTH OF THE STATE...AS A SHORTWAVE TROUGH
PUSHES EASTWARD FROM THE DATELINE ALONG 30N. THE 00Z SOUNDINGS
SHOW WELL-DEFINED INVERSIONS BASED AROUND 7500 FEET...WITH
SOMEWHAT BELOW NORMAL PWATS NEAR ONE INCH. MIMIC-TPW SATELLITE
IMAGERY INDICATES LITTLE VARIATION IN THE AIRMASS AROUND THE
ISLANDS...WITH ESTIMATED PWATS MOSTLY BETWEEN 1.0 AND 1.1 INCHES.

EXPECT LITTLE CHANGE OVERNIGHT...WITH SHOWERS AND CLOUDS
CONTINUING TO FOCUS WINDWARD...AND SOME SHOWERS SPILLING OVER
LEEWARD ON THE SMALLER ISLANDS. THE EXISTING FORECAST IS ON
TRACK...AND NO CHANGES ARE PLANNED FOR THIS EVENING.

MODERATE TO FRESH TRADES WILL CONTINUE ACROSS THE STATE ON
MONDAY...AS THE SFC HIGH PASSES BY TO OUR NORTH. HEIGHTS WILL
BEGIN TO FALL ALOFT...AS A MID/UPPER LEVEL TROUGH PUSHES EASTWARD
FROM THE DATELINE OVER THE NW HAWAIIAN ISLANDS. THIS WILL ALLOW
FOR THE INVERSION TO RISE AND WEAKEN SOMEWHAT...LIKELY KEEPING
TRADE WIND SHOWERS FAIRLY ACTIVE EVEN DURING THE AFTERNOON HOURS.

TRADES ARE EXPECTED TO WEAKEN MONDAY NIGHT AND TUESDAY...AS
THE MID/UPPER TROUGH PASSES NORTH OF THE STATE...AND A WEAK
SFC TROUGH DEVELOPS IN RESPONSE NEAR AND NORTH OF THE ISLANDS.
MODELS INDICATE THAT THE INVERSION WILL WEAKEN AND RISE A BIT
FURTHER DURING THIS TIME...WITH SOME MODEST INCREASE OF LOW LEVEL
MOISTURE AS WELL. THE TRADES MAY WEAKEN ENOUGH TO ALLOW SEABREEZES
TO DEVELOP ACROSS MANY AREAS ON TUESDAY AFTERNOON. INCREASED
MOISTURE/INSTABILITY COULD GENERATE A FEW HEAVIER DOWNPOURS MONDAY
NIGHT AND TUESDAY...POTENTIALLY ALSO ENHANCED BY SEABREEZE
CONVERGENCE TUESDAY AFTERNOON.

TRADE WINDS SHOULD INCREASE OVER THE ISLANDS ONCE AGAIN ON
WEDNESDAY AS THE MID LEVEL DISTURBANCE MOVES AWAY TO OUR NE AND
THE NEARBY LOW LEVEL TROUGH WASHES OUT. A SHORTWAVE MID LEVEL
RIDGE PASSING OVERHEAD SHOULD STRENGTHEN AND LOWER THE INVERSION
ONCE AGAIN AS WELL...THUS WOULD EXPECT TYPICAL TRADE WIND WEATHER
WITH MOSTLY LIGHT SHOWERS FOCUSING WINDWARD AND MAUKA.

FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
CLOUDS AND SHOWERS WILL REMAIN FOCUSED OVER WINDWARD SECTIONS OF
THE STATE THROUGH TONIGHT...AS MODERATE TO FRESH TRADE WINDS
PREVAIL. AIRMET SIERRA FOR MOUNTAIN OBSCURATION REMAINS IN EFFECT
FOR WINDWARD SECTIONS OF KAUAI...OAHU AND MOLOKAI.

VFR CONDITIONS WILL PREVAIL ELSEWHERE...WITH JUST ISOLATED MVFR
CEILINGS POSSIBLE AT TIMES MAINLY IN -SHRA.

AIRMET TANGO FOR MODERATE LOW LEVEL TURBULENCE HAS BEEN POSTED S
AND W OF THE MOUNTAINS DUE TO INCREASING TRADE WINDS.

&&

.MARINE...
NW SWELL APPEARS TO HAVE PEAKED AROUND MIDDAY SUNDAY AT BUOY 51101...
AND IS PROBABLY PEAKING NOW AT THE NEARSHORE CDIP BUOYS. RESULTING
SURF WILL BE NEAR ADVISORY LEVELS ALONG NORTH/WEST FACING SHORES
OF KAUAI...AND NORTH FACING SHORES OF OAHU/MOLOKAI/MAUI OVERNIGHT.
THIS SWELL AND SURF SHOULD BEGIN TO SUBSIDE LATE TONIGHT...AND
CONTINUE DROPPING MONDAY THROUGH TUESDAY.

OTHERWISE...SMALL SOUTH SWELL WILL CONTINUE PRODUCING SMALL SURF
ON SOUTH FACING SHORES THROUGH MID WEEK. A SMALL WNW SWELL MAY
ARRIVE INTO THE ISLANDS NEXT WEEKEND.

THE SUNDAY MORNING ASCAT PASS FOUND WINDS UP TO 25 KT IN THE
ALENUIHAHA CHANNEL...AND A SMALL CRAFT ADVISORY /SCA/ HAS BEEN
POSTED THERE AS WELL AS SOUTH OF THE BIG ISLAND. RECENT MESONET
DATA FROM MAALAEA BAY AND LANAI INDICATE THAT WINDS MAY BE NEAR 25
KT IN MAALAEA AND THE PAILOLO CHANNEL AS WELL. WILL CONSIDER
EXPANDING THE SCA INTO THOSE WATERS WITH THE EVENING FORECAST
UPDATE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 AM HST MONDAY FOR NORTH AND WEST FACING
SHORES OF KAUAI AND NIIHAU AND FOR NORTH FACING SHORES OF OAHU
MOLOKAI AND MAUI.

SMALL CRAFT ADVISORY UNTIL 6 PM HST MONDAY FOR ALENUIHAHA
CHANNEL-BIG ISLAND LEEWARD WATERS-BIG ISLAND SOUTHEAST WATERS.

&&

$$

JACOBSON








000
FXHW60 PHFO 300624
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
824 PM HST SUN MAR 29 2015

.SYNOPSIS...
A FAIRLY WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH MOST
OF THE UPCOMING WEEK...ALTHOUGH WINDS WILL BE RATHER LIGHT ON
TUESDAY. WHILE THE TRADE WINDS WILL FOCUS SHOWERS OVER WINDWARD
SLOPES AND COASTS...LEEWARD AREAS WILL SEE A FEW SHOWERS AS WELL.

&&

.DISCUSSION...
SCATTERED SHOWERS CONTINUE TO STREAM ACROSS MAINLY WINDWARD
SECTIONS OF THE STATE THIS EVENING. RAINFALL AMOUNTS HAVE BEEN
GENERALLY LIGHT...WITH MOST WINDWARD GAUGES RECORDING LESS THAN A
QUARTER INCH DURING THE PAST SIX HOURS. SURFACE ANALYSIS DEPICTS
A 1032 MB HIGH ABOUT 1000 MILES NW OF PHNL...WITH ANOTHER WEAKER
HIGH ABOUT 1200 MILES NE OF PHNL. A WEAK FRONT BETWEEN THESE TWO
HIGHS IS PASSING WELL NORTH OF THE STATE. MODERATE TO FRESH TRADES
PREVAIL OVER THE ISLANDS. ALOFT...A FLAT RIDGE AXIS IS BEING
GRADUALLY SUPPRESSED SOUTH OF THE STATE...AS A SHORTWAVE TROUGH
PUSHES EASTWARD FROM THE DATELINE ALONG 30N. THE 00Z SOUNDINGS
SHOW WELL-DEFINED INVERSIONS BASED AROUND 7500 FEET...WITH
SOMEWHAT BELOW NORMAL PWATS NEAR ONE INCH. MIMIC-TPW SATELLITE
IMAGERY INDICATES LITTLE VARIATION IN THE AIRMASS AROUND THE
ISLANDS...WITH ESTIMATED PWATS MOSTLY BETWEEN 1.0 AND 1.1 INCHES.

EXPECT LITTLE CHANGE OVERNIGHT...WITH SHOWERS AND CLOUDS
CONTINUING TO FOCUS WINDWARD...AND SOME SHOWERS SPILLING OVER
LEEWARD ON THE SMALLER ISLANDS. THE EXISTING FORECAST IS ON
TRACK...AND NO CHANGES ARE PLANNED FOR THIS EVENING.

MODERATE TO FRESH TRADES WILL CONTINUE ACROSS THE STATE ON
MONDAY...AS THE SFC HIGH PASSES BY TO OUR NORTH. HEIGHTS WILL
BEGIN TO FALL ALOFT...AS A MID/UPPER LEVEL TROUGH PUSHES EASTWARD
FROM THE DATELINE OVER THE NW HAWAIIAN ISLANDS. THIS WILL ALLOW
FOR THE INVERSION TO RISE AND WEAKEN SOMEWHAT...LIKELY KEEPING
TRADE WIND SHOWERS FAIRLY ACTIVE EVEN DURING THE AFTERNOON HOURS.

TRADES ARE EXPECTED TO WEAKEN MONDAY NIGHT AND TUESDAY...AS
THE MID/UPPER TROUGH PASSES NORTH OF THE STATE...AND A WEAK
SFC TROUGH DEVELOPS IN RESPONSE NEAR AND NORTH OF THE ISLANDS.
MODELS INDICATE THAT THE INVERSION WILL WEAKEN AND RISE A BIT
FURTHER DURING THIS TIME...WITH SOME MODEST INCREASE OF LOW LEVEL
MOISTURE AS WELL. THE TRADES MAY WEAKEN ENOUGH TO ALLOW SEABREEZES
TO DEVELOP ACROSS MANY AREAS ON TUESDAY AFTERNOON. INCREASED
MOISTURE/INSTABILITY COULD GENERATE A FEW HEAVIER DOWNPOURS MONDAY
NIGHT AND TUESDAY...POTENTIALLY ALSO ENHANCED BY SEABREEZE
CONVERGENCE TUESDAY AFTERNOON.

TRADE WINDS SHOULD INCREASE OVER THE ISLANDS ONCE AGAIN ON
WEDNESDAY AS THE MID LEVEL DISTURBANCE MOVES AWAY TO OUR NE AND
THE NEARBY LOW LEVEL TROUGH WASHES OUT. A SHORTWAVE MID LEVEL
RIDGE PASSING OVERHEAD SHOULD STRENGTHEN AND LOWER THE INVERSION
ONCE AGAIN AS WELL...THUS WOULD EXPECT TYPICAL TRADE WIND WEATHER
WITH MOSTLY LIGHT SHOWERS FOCUSING WINDWARD AND MAUKA.

FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
CLOUDS AND SHOWERS WILL REMAIN FOCUSED OVER WINDWARD SECTIONS OF
THE STATE THROUGH TONIGHT...AS MODERATE TO FRESH TRADE WINDS
PREVAIL. AIRMET SIERRA FOR MOUNTAIN OBSCURATION REMAINS IN EFFECT
FOR WINDWARD SECTIONS OF KAUAI...OAHU AND MOLOKAI.

VFR CONDITIONS WILL PREVAIL ELSEWHERE...WITH JUST ISOLATED MVFR
CEILINGS POSSIBLE AT TIMES MAINLY IN -SHRA.

AIRMET TANGO FOR MODERATE LOW LEVEL TURBULENCE HAS BEEN POSTED S
AND W OF THE MOUNTAINS DUE TO INCREASING TRADE WINDS.

&&

.MARINE...
NW SWELL APPEARS TO HAVE PEAKED AROUND MIDDAY SUNDAY AT BUOY 51101...
AND IS PROBABLY PEAKING NOW AT THE NEARSHORE CDIP BUOYS. RESULTING
SURF WILL BE NEAR ADVISORY LEVELS ALONG NORTH/WEST FACING SHORES
OF KAUAI...AND NORTH FACING SHORES OF OAHU/MOLOKAI/MAUI OVERNIGHT.
THIS SWELL AND SURF SHOULD BEGIN TO SUBSIDE LATE TONIGHT...AND
CONTINUE DROPPING MONDAY THROUGH TUESDAY.

OTHERWISE...SMALL SOUTH SWELL WILL CONTINUE PRODUCING SMALL SURF
ON SOUTH FACING SHORES THROUGH MID WEEK. A SMALL WNW SWELL MAY
ARRIVE INTO THE ISLANDS NEXT WEEKEND.

THE SUNDAY MORNING ASCAT PASS FOUND WINDS UP TO 25 KT IN THE
ALENUIHAHA CHANNEL...AND A SMALL CRAFT ADVISORY /SCA/ HAS BEEN
POSTED THERE AS WELL AS SOUTH OF THE BIG ISLAND. RECENT MESONET
DATA FROM MAALAEA BAY AND LANAI INDICATE THAT WINDS MAY BE NEAR 25
KT IN MAALAEA AND THE PAILOLO CHANNEL AS WELL. WILL CONSIDER
EXPANDING THE SCA INTO THOSE WATERS WITH THE EVENING FORECAST
UPDATE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 AM HST MONDAY FOR NORTH AND WEST FACING
SHORES OF KAUAI AND NIIHAU AND FOR NORTH FACING SHORES OF OAHU
MOLOKAI AND MAUI.

SMALL CRAFT ADVISORY UNTIL 6 PM HST MONDAY FOR ALENUIHAHA
CHANNEL-BIG ISLAND LEEWARD WATERS-BIG ISLAND SOUTHEAST WATERS.

&&

$$

JACOBSON









000
FXHW60 PHFO 300624
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
824 PM HST SUN MAR 29 2015

.SYNOPSIS...
A FAIRLY WET TRADE WIND WEATHER PATTERN WILL PREVAIL THROUGH MOST
OF THE UPCOMING WEEK...ALTHOUGH WINDS WILL BE RATHER LIGHT ON
TUESDAY. WHILE THE TRADE WINDS WILL FOCUS SHOWERS OVER WINDWARD
SLOPES AND COASTS...LEEWARD AREAS WILL SEE A FEW SHOWERS AS WELL.

&&

.DISCUSSION...
SCATTERED SHOWERS CONTINUE TO STREAM ACROSS MAINLY WINDWARD
SECTIONS OF THE STATE THIS EVENING. RAINFALL AMOUNTS HAVE BEEN
GENERALLY LIGHT...WITH MOST WINDWARD GAUGES RECORDING LESS THAN A
QUARTER INCH DURING THE PAST SIX HOURS. SURFACE ANALYSIS DEPICTS
A 1032 MB HIGH ABOUT 1000 MILES NW OF PHNL...WITH ANOTHER WEAKER
HIGH ABOUT 1200 MILES NE OF PHNL. A WEAK FRONT BETWEEN THESE TWO
HIGHS IS PASSING WELL NORTH OF THE STATE. MODERATE TO FRESH TRADES
PREVAIL OVER THE ISLANDS. ALOFT...A FLAT RIDGE AXIS IS BEING
GRADUALLY SUPPRESSED SOUTH OF THE STATE...AS A SHORTWAVE TROUGH
PUSHES EASTWARD FROM THE DATELINE ALONG 30N. THE 00Z SOUNDINGS
SHOW WELL-DEFINED INVERSIONS BASED AROUND 7500 FEET...WITH
SOMEWHAT BELOW NORMAL PWATS NEAR ONE INCH. MIMIC-TPW SATELLITE
IMAGERY INDICATES LITTLE VARIATION IN THE AIRMASS AROUND THE
ISLANDS...WITH ESTIMATED PWATS MOSTLY BETWEEN 1.0 AND 1.1 INCHES.

EXPECT LITTLE CHANGE OVERNIGHT...WITH SHOWERS AND CLOUDS
CONTINUING TO FOCUS WINDWARD...AND SOME SHOWERS SPILLING OVER
LEEWARD ON THE SMALLER ISLANDS. THE EXISTING FORECAST IS ON
TRACK...AND NO CHANGES ARE PLANNED FOR THIS EVENING.

MODERATE TO FRESH TRADES WILL CONTINUE ACROSS THE STATE ON
MONDAY...AS THE SFC HIGH PASSES BY TO OUR NORTH. HEIGHTS WILL
BEGIN TO FALL ALOFT...AS A MID/UPPER LEVEL TROUGH PUSHES EASTWARD
FROM THE DATELINE OVER THE NW HAWAIIAN ISLANDS. THIS WILL ALLOW
FOR THE INVERSION TO RISE AND WEAKEN SOMEWHAT...LIKELY KEEPING
TRADE WIND SHOWERS FAIRLY ACTIVE EVEN DURING THE AFTERNOON HOURS.

TRADES ARE EXPECTED TO WEAKEN MONDAY NIGHT AND TUESDAY...AS
THE MID/UPPER TROUGH PASSES NORTH OF THE STATE...AND A WEAK
SFC TROUGH DEVELOPS IN RESPONSE NEAR AND NORTH OF THE ISLANDS.
MODELS INDICATE THAT THE INVERSION WILL WEAKEN AND RISE A BIT
FURTHER DURING THIS TIME...WITH SOME MODEST INCREASE OF LOW LEVEL
MOISTURE AS WELL. THE TRADES MAY WEAKEN ENOUGH TO ALLOW SEABREEZES
TO DEVELOP ACROSS MANY AREAS ON TUESDAY AFTERNOON. INCREASED
MOISTURE/INSTABILITY COULD GENERATE A FEW HEAVIER DOWNPOURS MONDAY
NIGHT AND TUESDAY...POTENTIALLY ALSO ENHANCED BY SEABREEZE
CONVERGENCE TUESDAY AFTERNOON.

TRADE WINDS SHOULD INCREASE OVER THE ISLANDS ONCE AGAIN ON
WEDNESDAY AS THE MID LEVEL DISTURBANCE MOVES AWAY TO OUR NE AND
THE NEARBY LOW LEVEL TROUGH WASHES OUT. A SHORTWAVE MID LEVEL
RIDGE PASSING OVERHEAD SHOULD STRENGTHEN AND LOWER THE INVERSION
ONCE AGAIN AS WELL...THUS WOULD EXPECT TYPICAL TRADE WIND WEATHER
WITH MOSTLY LIGHT SHOWERS FOCUSING WINDWARD AND MAUKA.

FORECAST UNCERTAINTY INCREASES FROM THURSDAY INTO NEXT WEEKEND...
DUE TO MODEL VARIATIONS IN THE EVOLUTION OF A COMPLEX DEEP LAYERED
TROUGH DEVELOPING OVER THE CENTRAL PACIFIC. MOST OF THE MODELS VEER
AND WEAKEN TRADE WIND FLOW LOCALLY TO SOME EXTENT...WITH THE
SMALLER ISLANDS POSSIBLY FALLING WITHIN THE RAIN SHADOW OF THE
BIG ISLAND. AS NOTED PREVIOUSLY...A 10-20 DEGREE DIFFERENCE IN
WIND DIRECTION WOULD HAVE SIGNIFICANT IMPLICATIONS FOR SENSIBLE
WEATHER OVER THE ISLANDS DURING THIS TIME. FORECAST MODELS HAVE
BEEN INCONSISTENT WITH THEIR SOLUTIONS FOR EARLY THIS WEEK...
THEREFORE CONFIDENCE IN THE LATER PERIOD FORECASTS IS NOT
PARTICULARLY HIGH AT THIS TIME.

&&

.AVIATION...
CLOUDS AND SHOWERS WILL REMAIN FOCUSED OVER WINDWARD SECTIONS OF
THE STATE THROUGH TONIGHT...AS MODERATE TO FRESH TRADE WINDS
PREVAIL. AIRMET SIERRA FOR MOUNTAIN OBSCURATION REMAINS IN EFFECT
FOR WINDWARD SECTIONS OF KAUAI...OAHU AND MOLOKAI.

VFR CONDITIONS WILL PREVAIL ELSEWHERE...WITH JUST ISOLATED MVFR
CEILINGS POSSIBLE AT TIMES MAINLY IN -SHRA.

AIRMET TANGO FOR MODERATE LOW LEVEL TURBULENCE HAS BEEN POSTED S
AND W OF THE MOUNTAINS DUE TO INCREASING TRADE WINDS.

&&

.MARINE...
NW SWELL APPEARS TO HAVE PEAKED AROUND MIDDAY SUNDAY AT BUOY 51101...
AND IS PROBABLY PEAKING NOW AT THE NEARSHORE CDIP BUOYS. RESULTING
SURF WILL BE NEAR ADVISORY LEVELS ALONG NORTH/WEST FACING SHORES
OF KAUAI...AND NORTH FACING SHORES OF OAHU/MOLOKAI/MAUI OVERNIGHT.
THIS SWELL AND SURF SHOULD BEGIN TO SUBSIDE LATE TONIGHT...AND
CONTINUE DROPPING MONDAY THROUGH TUESDAY.

OTHERWISE...SMALL SOUTH SWELL WILL CONTINUE PRODUCING SMALL SURF
ON SOUTH FACING SHORES THROUGH MID WEEK. A SMALL WNW SWELL MAY
ARRIVE INTO THE ISLANDS NEXT WEEKEND.

THE SUNDAY MORNING ASCAT PASS FOUND WINDS UP TO 25 KT IN THE
ALENUIHAHA CHANNEL...AND A SMALL CRAFT ADVISORY /SCA/ HAS BEEN
POSTED THERE AS WELL AS SOUTH OF THE BIG ISLAND. RECENT MESONET
DATA FROM MAALAEA BAY AND LANAI INDICATE THAT WINDS MAY BE NEAR 25
KT IN MAALAEA AND THE PAILOLO CHANNEL AS WELL. WILL CONSIDER
EXPANDING THE SCA INTO THOSE WATERS WITH THE EVENING FORECAST
UPDATE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 AM HST MONDAY FOR NORTH AND WEST FACING
SHORES OF KAUAI AND NIIHAU AND FOR NORTH FACING SHORES OF OAHU
MOLOKAI AND MAUI.

SMALL CRAFT ADVISORY UNTIL 6 PM HST MONDAY FOR ALENUIHAHA
CHANNEL-BIG ISLAND LEEWARD WATERS-BIG ISLAND SOUTHEAST WATERS.

&&

$$

JACOBSON









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