High Surf in Hawaii, May 6 to 7, 2015

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST WED MAY 6 2015

CORRECTED GRAMMAR IN DISCUSSION

.SYNOPSIS...
MODERATE TO FRESH TRADE WINDS WILL CONTINUE THROUGH THURSDAY...
INCREASE ON FRIDAY...AND THEN REMAIN STRONG THROUGH THE WEEKEND
AND INTO NEXT WEEK. CLOUDS AND SHOWERS WILL BE MOST ACTIVE OVER
WINDWARD SLOPES AND COASTS DURING NIGHTS AND MORNINGS...ALTHOUGH
SHOWERS WILL OCCASIONALLY MOVE OVER LEEWARD AREAS.

&&

.DISCUSSION...
BREEZY TRADE WIND WEATHER DOMINATES THE ISLAND WEATHER FORECAST FOR
THE FORESEEABLE FUTURE...WITH THE TRADE WINDS DELIVERING PATCHES OF
CLOUDS AND SHOWERS THAT WILL FOCUS OVER WINDWARD SLOPES AND COASTS...
AND BE MOST ACTIVE DURING NIGHTS AND MORNINGS. WITH A SOMEWHAT
ELEVATED INVERSION BASE AND TRADE WINDS EXTENDING AS HIGH AS 10
KFT...SHOWERS WILL OCCASIONALLY SPREAD TO LEEWARD AREAS OF THE
SMALLER ISLANDS. THE TRADE WINDS ARE CURRENTLY BEING SUPPLIED BY A
SURFACE HIGH TO THE DISTANT NE OF THE ISLANDS...WITH A NEW HIGH
BUILDING N OF THE ISLANDS BY WEEK/S END PROMOTING AN INCREASE IN
WIND SPEEDS. NO NOTEWORTHY FEATURES ALOFT ARE EXPECTED TO
SIGNIFICANTLY ENHANCE INCOMING MOISTURE INTO THE WEEKEND...BUT A
SHARPENING MID AND UPPER LEVEL TROUGH IS EXPECTED FROM SUNDAY INTO
EARLY NEXT WEEK. THIS COULD POTENTIALLY ACT TO WEAKEN THE SUBSIDENCE
INVERSION AND LEAD TO A GREATER NUMBER OF TRADE WIND SHOWERS.

&&

.AVIATION...
MODERATE TO FRESH TRADE WINDS WILL CONTINUE THROUGH THURSDAY.
THUS AIRMET TANGO FOR LOW LEVEL TURB OVER AND SW THRU W OF THE
MTNS...MAINLY THOSE ALIGNED FROM N TO S DUE TO THE EASTERLY
COMPONENT OF THE WINDS...WILL REMAIN POSTED UNDER THE BRISK WINDS.

RANDOM AREAS OF LOW CLOUDS EMBEDDED WITHIN THE TRADE WIND FLOW WILL
OCCASIONALLY MOVE THROUGH THE ISLANDS...RESULTING IN BRIEF MVFR
CEILING TYPICALLY ALONG WINDWARD AREAS. SOME OF THE LOW CLOUDS MAY
REACH THE LEE AREAS OF THE SMALLER ISLANDS. REGARDLESS...EXPECT
MAINLY VFR CONDITIONS TO PREVAIL FOR THE SITES.

&&

.MARINE...
A SMALL CRAFT ADVISORY /SCA/ REMAINS IN EFFECT THROUGH FRIDAY FOR
THE TYPICALLY WINDIER MARINE ZONES AROUND MAUI AND THE BIG ISLAND.
THE SCA FOR THESE AREAS WILL ALMOST UNDOUBTEDLY NEED TO BE EXTENDED
THROUGH THE WEEKEND AS A NEW HIGH BUILDS N OF THE ISLANDS...WITH
NEAR GALE FORCE WINDS ANTICIPATED IN SOME CHANNELS. THE SCA MAY ALSO
NEED TO BE EXPANDED TO OTHER MARINE ZONES THIS WEEKEND.

THE TRADE WINDS WILL MAINTAIN ELEVATED SHORT PERIOD SURF ALONG E
FACING SHORES THROUGH THE PERIOD...THOUGH HEIGHTS SHOULD REMAIN
BELOW THE ADVISORY THRESHOLD. WAVE WATCH GUIDANCE INDICATES LARGEST
WAVES ALONG E FACING SHORES WILL OCCUR THIS WEEKEND.

AN ANTICIPATED LONG-PERIOD SSW SWELL IS CURRENTLY IN THE PROCESS OF
MOVING THROUGH HAWAIIAN WATERS...AND A HIGH SURF ADVISORY IS IN
EFFECT FOR S FACING SHORES. BUOYS NEAR THE ISLANDS ARE INDICATING
THAT THE PEAK ENERGY OF THE SWELL HAS SHIFTED FROM NEAR 20 SECONDS
TO NEAR 16 SECONDS...WHICH SHOULD LEAD TO SHORTER LULLS BETWEEN
SETS. THE EXPECTATION IS THAT THE SWELL WILL PEAK TODAY...AND THEN
GRADUALLY LOWER INTO THE WEEKEND AS SEVERAL SMALLER PULSES OF
LONG-PERIOD SWELL ARRIVE FROM THE S HEMISPHERE. OTHERWISE...A
TINY N SWELL CONTINUES TO ARRIVE...WITH A SLIGHTLY LARGER NNW
SWELL EXPECTED FROM THURSDAY INTO SATURDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 10 AM HST THURSDAY FOR SOUTH FACING
SHORES OF NIIHAU KAUAI OAHU MOLOKAI MAUI KAHOOLAWE AND THE BIG
ISLAND.

SMALL CRAFT ADVISORY UNTIL 6 PM HST FRIDAY FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.

&&

DISCUSSION/MARINE...BIRCHARD
AVIATION...FUJII