Area Forecast Discussion
Issued by NWS Honolulu, HI

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000
FXHW60 PHFO 271332
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
332 AM HST THU NOV 27 2014

.SYNOPSIS...
A RATHER DRY TRADE WIND PATTERN WILL PREVAIL ACROSS MOST OF THE
STATE THROUGH THE NEXT COUPLE OF DAYS...BUT LINGERING LOW LEVEL
MOISTURE WILL CONTINUE TO GENERATE SCATTERED SHOWER ACTIVITY
ACROSS WINDWARD PORTIONS OF THE BIG ISLAND AND MAUI. SURFACE HIGH
PRESSURE NORTH OF THE ISLANDS WILL DRIVE STRONG TRADE WINDS
ACROSS THE STATE THROUGH THE END OF THIS WEEK AND INTO THE
WEEKEND. TRADES SHOULD SLACKEN A BIT EARLY NEXT WEEK...WITH
SHOWERS REMAINING FOCUSED MAINLY ACROSS WINDWARD AREAS.

&&

.DISCUSSION...
BREEZY AND RATHER DRY CONDITIONS HAVE CONTINUED ACROSS MOST OF
THE STATE OVERNIGHT. SOME AREAS ON THE WINDWARD BIG ISLAND AND ON
THE WINDWARD SLOPES OF HALEAKALA CONTINUE TO RECEIVE MEASURABLE
RAINFALL AMOUNTS...WITH TRACE AMOUNTS BEING RECORDED AT SOME OF
THE WINDWARD STATIONS ON MOLOKAI AND OAHU. SURFACE ANALYSIS
DEPICTS A 1028 MB HIGH CENTERED 1200 MILES NNW OF KAUAI...WITH
FRESH TO LOCALLY STRONG TRADE WIND FLOW PREVAILING OVER THE MAIN
HAWAIIAN ISLANDS. THE 12Z LIHUE SOUNDING FOUND A DRY AND VERY
STABLE PROFILE...WITH A STRONG INVERSION BASED NEAR 5000 FEET AND
PWAT OF ONLY 0.76 INCHES. THE 12Z HILO SOUNDING REFLECTED THE
SLIGHTLY DEEPER MOISTURE LINGERING NEAR THE BIG ISLAND...WITH AN
INVERSION BASED AROUND 6500 FEET AND PWAT OF 1.10 INCHES. MIMIC-
TPW SATELLITE IMAGERY DEPICTS A DRY ATMOSPHERE AROUND AND NORTH OF
THE ISLANDS...WITH DEEPER TROPICAL MOISTURE CONFINED WELL TO THE
SOUTH OF THE BIG ISLAND.

A BREEZY...STABLE AND MAINLY DRY TRADE WIND PATTERN WILL PREVAIL
THROUGH THE NEXT SEVERAL DAYS. THE SURFACE HIGH INITIALLY TO OUR
NNW IS FORECAST TO BUILD SLOWLY EASTWARD TO THE NORTH OF THE STATE
BETWEEN 30N AND 40N THROUGH THE REST OF THIS WEEK AND INTO THE
WEEKEND. BREEZY CONDITIONS WILL BE WIDESPREAD OVER LAND AREAS
DURING THIS TIME AS FRESH TO STRONG TRADE WINDS PREVAIL. THE HIGH
RESOLUTION UH-WRF MODEL IS DEPICTING SUSTAINED WINDS OF 25 KNOTS
OR GREATER ACROSS PARTS OF THE BIG ISLAND TODAY...AND RECENT OBS
SHOW WINDS ALREADY NEAR ADVISORY CRITERIA AT TIMES ON LANAI. A
WIND ADVISORY HAS BEEN ISSUED FOR PARTS OF MAUI COUNTY AND THE BIG
ISLAND THROUGH 6 PM TODAY. IF WINDS VERIFY TODAY AS MODELS
INDICATE...THIS ADVISORY WOULD LIKELY NEED TO BE EXTENDED THROUGH
AT LEAST FRIDAY.

OTHERWISE...SHOWERS WILL BE MAINLY CONFINED TO WINDWARD AND MAUKA
AREAS THROUGH THE WEEKEND...WITH THE BEST RAIN CHANCES REMAINING
ACROSS THE WINDWARD BIG ISLAND. BLENDED MODEL DATA KEEPS PWATS
NEAR OR BELOW ONE INCH (BELOW THE 25TH PERCENTILE FOR THIS TIME OF
YEAR). THEREFORE WOULD EXPECT RAINFALL AMOUNTS TO REMAIN MOSTLY
ON THE LIGHT SIDE.

TRADE WINDS SHOULD SLACKEN A BIT EARLY NEXT WEEK...AS THE SURFACE
HIGH TO OUR NORTH WEAKENS. A MODEST INCREASE IN LOW LEVEL MOISTURE
MAY TAKE PLACE...AND A VERY WEAK FRONT OR SHEAR LINE MAY PASS
THROUGH THE STATE AROUND NEXT WEDNESDAY. WITH THE ADDED MOISTURE
WINDWARD/MAUKA SHOWERS COULD INCREASE SOMEWHAT...BUT OVERALL DO NOT
EXPECT ANY MAJOR CHANGES TO THE WEATHER PATTERN.

&&

.AVIATION...
FRESH AND GUSTY TRADE WINDS WILL CONTINUE FOR THE NEXT SEVERAL
PERIODS. WIND SPEEDS IN SOME AREAS ARE LIKELY TO EXCEED 20 TO 25 KT
WITH HIGHER GUSTS...ESPECIALLY OVER MOUNTAIN RIDGES AND THROUGH
VALLEYS. AIRMET TANGO FOR LOW LEVEL TURB IS EXPECTED TO REMAIN
POSTED DURING THIS TIME.

EARLY MORNING SOUNDINGS SHOW A STRONG LOW LEVEL INVERSION BETWEEN 5
AND 6 KFT. PRECIPITABLE WATER AMOUNTS RANGE FROM 0.76 INCHES IN
LIHUE TO 1.1 INCHES IN HILO. WINDWARD SHOWERS OVERNIGHT HAVE BEEN
SLIGHTLY MORE ACTIVE OVER THE EASTERN ISLANDS...BUT ALL IN ALL HAVE
REMAINED FAIRLY SHALLOW. CONDITIONS SHOULD REMAIN SIMILAR...WITH
VFR THROUGHOUT THANKSGIVING DAY.

&&

.MARINE...
NORTH-NORTHEAST SWELL APPEARS TO HAVE PEAKED AT THE WAIMEA BAY
AND PAUWELA CDIP BUOYS...BUT CONTINUES TO RUN ABOVE WAVEWATCH
GUIDANCE. THIS SWELL IS FORECAST TO GRADUALLY SUBSIDE THROUGH
TODAY...BUT GIVEN OBSERVATION TRENDS WILL MAINTAIN THE EXISTING
HIGH SURF ADVISORY FOR NORTH AND EAST FACING SHORES THROUGH 6 PM.
THE LARGE NNE SWELL MAY ALSO CAUSE HARBOR SURGES WITHIN KAHULUI
AND HILO HARBORS THROUGH TODAY...AND A MARINE WEATHER STATEMENT
HAS BEEN ISSUED.

A COMBINATION OF LINGERING MODERATE NNE SWELL AND SHORT PERIOD
WIND WAVES DRIVEN BY STRONG TRADES WILL MAINTAIN ELEVATED SURF
ACROSS NORTH AND EAST FACING SHORES FROM FRIDAY THROUGH THE
WEEKEND. THERE IS A STRONG POSSIBILITY THAT THE HIGH SURF
ADVISORY WILL NEED TO BE EXTENDED FOR EAST FACING SHORES BEYOND
TODAY.

THE OVERNIGHT ASCAT PASS MISSED THE HAWAIIAN COASTAL WATERS...
BUT DID FIND LARGE AREAS OF 25 KNOT WINDS WELL WEST AND SOUTHWEST
OF KAUAI. THE WEDNESDAY MORNING ASCAT PASS FOUND 25 KNOT WINDS IN
THE ALENUIHAHA CHANNEL AND SOUTH OF THE BIG ISLAND...WITH WINDS
NEAR 20 KNOTS IN THE KAIWI AND KAUAI CHANNELS. TRADES HAVE
INCREASED FURTHER SINCE THEN WITH HIGH PRESSURE BUILDING NORTH OF
THE STATE...AND THE COMBINATION OF WIND WAVES AND LARGE NNE SWELL
IS STILL GENERATING COMBINED SEAS OF 10 FEET OR HIGHER ACROSS MANY
AREAS. A SMALL CRAFT ADVISORY /SCA/ REMAINS POSTED FOR ALL OF THE
HAWAIIAN COASTAL WATERS. SCA CONDITIONS WILL LIKELY CONTINUE FOR
MOST OF THE WATERS THROUGH THE REST OF THIS WEEK.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 PM HST THIS EVENING FOR ALL NORTH
AND EAST FACING SHORES EXCEPT FOR LANAI AND KAHOOLAWE.

WIND ADVISORY UNTIL 6 PM HST THIS EVENING FOR LANAI-KAHOOLAWE-
MAUI CENTRAL VALLEY-SOUTH BIG ISLAND-BIG ISLAND NORTH AND EAST-
KOHALA.

SMALL CRAFT ADVISORY UNTIL 6 AM HST SATURDAY FOR KAUAI NORTHWEST
WATERS-OAHU LEEWARD WATERS-KAIWI CHANNEL-MAALAEA BAY-PAILOLO
CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG ISLAND
SOUTHEAST WATERS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR KAUAI
WINDWARD WATERS-KAUAI LEEWARD WATERS-KAUAI CHANNEL-OAHU WINDWARD
WATERS-MAUI COUNTY WINDWARD WATERS-MAUI COUNTY LEEWARD WATERS-
BIG ISLAND WINDWARD WATERS.

&&

$$

DISCUSSION/MARINE...JACOBSON
AVIATION...EATON





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