High Surf in Hawaii, June 13 to 14, 2013

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
340 AM HST THU JUN 13 2013

.SYNOPSIS...
BREEZY TRADE WINDS WILL CONTINUE WELL INTO NEXT WEEK...BUT WILL BE
ESPECIALLY STRONG TODAY THROUGH FRIDAY. LOW CLOUDS AND SHOWERS
CARRIED IN BY THE TRADES WILL FOCUS OVER WINDWARD AREAS...BUT SOME
SHOWERS WILL BE CARRIED LEEWARD BY THE STRONG TRADES. LEEWARD BIG
ISLAND WILL HAVE THE TYPICAL SUMMERTIME AFTERNOON AND EVENING
CLOUDINESS...WITH A FEW SHOWERS OVER THE SLOPES.

&&

.DISCUSSION...
LITTLE CHANGE IN ONGOING FORECAST PHILOSOPHY. TRADE WIND WEATHER
WILL PREVAIL...WITH STRONGER WINDS AND SOMEWHAT WETTER CONDITIONS IN
THE SHORT TERM.

CURRENTLY...BREEZY TRADE WINDS ARE BEING SUPPORTED BY A PAIR OF
SURFACE HIGH PRESSURE SYSTEMS...CENTERED TO THE N AND NE OF THE
ISLANDS. WHILE MODEL ANALYSES CONTINUE TO INDICATE THAT THE ISLANDS
ARE UNDER THE INFLUENCE OF A STRONG MID-LEVEL RIDGE...THE ASSOCIATED
SUBSIDENCE INVERSION HAS WEAKENED SOMEWHAT...AND RISEN TO BETWEEN 8
AND 10 THOUSAND FEET...BASED ON 12Z SOUNDINGS. WHILE THIS IS NOT
ALLOWING SHOWERS TO BECOME HEAVY...THE DEEPER MIXED LAYER HAS
ALLOWED FOR GREATER COVERAGE OF TRADE SHOWERS...WITH THE INCOMING
CLOUD FIELD APPEARING QUITE SHOWERY.

THE HIGH TO THE NE WILL MOVE S TODAY...AND THEN MERGE WITH THE HIGH
TO THE N TONIGHT AND FRIDAY...WITH THIS BECOMING THE DOMINANT HIGH
THEREAFTER. TRADE WINDS OVER THE ISLANDS WILL INCREASE IN THE SHORT
TERM...AND WILL BE QUITE GUSTY THROUGH FRIDAY. WINDS WILL GRADUALLY
EASE OVER THE WEEKEND AS THE HIGH MOVES SLOWLY ESE AND WEAKENS
SLIGHTLY. THIS HIGH WILL THEN CONTINUE TO SUPPORT MODERATE TO
LOCALLY FRESH TRADE WINDS THROUGH THE MIDDLE OF NEXT WEEK...WITH
WINDS POTENTIALLY DROPPING ANOTHER NOTCH AROUND THE END OF NEXT WEEK
AS A TROUGH DEVELOPS NW OF THE ISLANDS.

WITH THE SOMEWHAT RELAXED CAP AND STRONG TRADE WINDS...PASSING
SHOWERS WILL BE MORE FREQUENT OVER WINDWARD COASTS AND SLOPES
THROUGH FRIDAY...WITH THE STRONG TRADES ABLE TO SEND A FEW OF THESE
SHOWERS LEEWARD ON THE SMALLER ISLANDS. THE INCREASED WINDS HAVE LED
TO THE ISSUANCE OF A WIND ADVISORY FOR AREAS WHERE THE WIND IS MOST
ACCELERATED BY ISLAND TERRAIN...AND FOR THE SUMMITS ON MAUI AND THE
BIG ISLAND.

A MID-LEVEL WEAKNESS DEVELOPING LATE THIS WEEKEND MAY KEEP TRADE
SHOWERS SOMEWHAT ACTIVE DESPITE THE EASING WIND SPEEDS...BUT LEEWARD
AREAS SHOULD STILL SEE PLENTY OF AFTERNOON SUN...ESPECIALLY SINCE
THE RECENT RUN OF HIGH CLOUDINESS IS ENDING.

&&

.AVIATION...
STRONG TRADES ENE G35-45KT AND OCCASIONALLY STRONGER STILL EXPECTED.
AIRMET TANGO REMAINS POSTED FOR MOD LEE TURB AOB 070. POSSIBLY AREAS
OF SEVERE TURB MAY BE POSSIBLE...ESPECIALLY AFT 20Z. THE TYPICALLY
WINDIEST TERMINALS WILL SEE SIGNIFICANT CHOP DURA.

OCNL SHRA WILL STILL FOCUS MVFR COND ALG WINDWARD TERRAIN. WINDWARD
TERMINALS WILL SEE PERIODS OF MVFR CIGS THROUGH AT LEAST 19Z-21Z.
OTHERWISE MAINLY VFR WILL BE THE RULE.

&&

.MARINE...
A SMALL CRAFT ADVISORY /SCA/ IS IN EFFECT FOR ALL HAWAIIAN WATERS...
WITH A GALE WARNING IN EFFECT FOR THE ALENUIHAHA CHANNEL TODAY.
DEPENDING ON HOW THINGS PAN OUT TODAY...THE GALE MAY NEED TO BE
EXTENDED IN TIME...AND POSSIBLY IN AREA...TO INCLUDE A FEW OTHER
WINDY MARINE ZONES AROUND MAUI AND THE BIG ISLAND.

WINDWARD NEAR SHORE BUOYS SHOWING SHORT-PERIOD SEAS HAVE INCREASED
SINCE YESTERDAY...WITH LATEST OBSERVATIONS INDICATING 8-10 FOOT
SEAS WITH A DOMINANT PERIOD NEAR 9 SECONDS. THIS SUPPORTS BOTH THE
SCA...AND THE NEED FOR A HIGH SURF ADVISORY FOR E FACING SHORES...
WITH THE HIGH SURF EXPECTED TO CONTINUE THROUGH FRIDAY. SURF WILL
REMAIN ON THE SMALL SIDE ALONG OTHER SHORES INTO NEXT WEEK.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 PM FRIDAY FOR EAST FACING SHORES OF KAUAI
OAHU MOLOKAI MAUI AND THE BIG ISLAND.

SMALL CRAFT ADVISORY UNTIL 6 PM HST FRIDAY FOR ALL HAWAIIAN
WATERS...EXCEPT GALE WARNING FOR ALENUIHAHA CHANNEL UNTIL 6 PM
TODAY.

WIND ADVISORY UNTIL 6 PM TODAY FOR KAHOOLAWE-HALEAKALA SUMMIT-SOUTH
BIG ISLAND-BIG ISLAND NORTH AND EAST-KOHALA-BIG ISLAND INTERIOR-BIG
ISLAND SUMMITS.

&&

DISCUSSION/MARINE...BIRCHARD
AVIATION...DEJESUS