High Surf in Hawaii, March 16 to 17, 2013

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST SAT MAR 16 2013

.SYNOPSIS...
THE REMAINS OF A COLD FRONT ARE FOUND OVER THE NORTHERN BIG ISLAND
THIS MORNING...WHILE AN UPPER LEVEL TROUGH REMAINS OVER THE
ISLANDS. THE UPPER LEVEL TROUGH WILL HELP TO BRING SHOWERS TO THE
HIGHER ELEVATIONS OF THE BIG ISLAND...AND WINTER WEATHER TO THE BIG
ISLAND SUMMITS. DRIER WEATHER IS FOUND BEHIND THE FRONT...WHICH IS
EXPECTED TO PERSIST OVER THE ISLANDS BEHIND THE FRONT THROUGH SUNDAY.

&&

.DISCUSSION...
THE FRONT HAS NOT BEEN THE GREAT RAIN PRODUCER WE THOUGHT IT MIGHT
BE...HOWEVER SHOWERS ARE MAKING IT OVER PORTIONS OF MAUI AND THE BIG
ISLAND THIS MORNING. AT THIS TIME...SHOWERS CONTINUE TO MOVE FAST
ENOUGH NOT TO BE CAUSING MANY ISSUES WITH LOCAL FLOODING.

THE SUMMITS OF THE BIG ISLAND REMAIN THE BIG STORY. THE 12Z SOUNDING
AT HILO HAD 600 MB WINDS OF 43 KTS. THE HIGHEST PEAK WIND OBSERVED
AT THE SUMMIT SO FAR WAS JUST BEFORE 7 AM OF 108 MPH. SUSTAINED
WINDS ON THE SUMMIT RANGE ANY WHERE FROM 30 TO 80 MPH THIS
MORNING...CONTINUING HAZARDOUS CONDITIONS THERE. AS THE FRONT EDGES
CLOSER TO THE BIG ISLAND INTERIOR...AND CLOUDS THICKEN OVER THE
SUMMIT AREAS...THE THREAT FOR SNOW WILL COMPOUND THE HAZARDOUS
CONDITIONS. THE MODELS SHOW 50 KT WINDS AT 600 MB LINGERING NEAR THE
BIG ISLAND THROUGH TONIGHT AND INTO TOMORROW...SO THE HIGH WIND
WARNING CONTINUES THROUGH SUNDAY.

WE/RE WATCHING THE FRONT CLOSELY TO SEE HOW THE WINTER SITUATION
PANS OUT ON THE SUMMITS. WHILE THE PREVIOUS FORECAST PHILOSOPHY
ANTICIPATED UP TO 2 INCHES FALLING AT THE SUMMIT BY NOW...NO SNOW
HAS BEEN REPORTED THUS FAR. WE/RE STICKING WITH THE UP TO 5 INCHES
TOTAL ACCUMULATION AT THIS POINT SINCE THE SLOWER MOVING SYSTEM
COULD STILL BRING IN MORE SNOW. THE WINTER WEATHER ADVISORY FOR THE
SUMMITS CONTINUES THROUGH TODAY...AND WE/LL SEE HOW THE DAY
PROGRESSES TO DETERMINE IF THE EVENT WILL CONTINUE INTO TONIGHT OR
NOT.

THE MODELS SHOW THE SURFACE FRONT CONTINUING TO WEAKEN AS ITS
ASSOCIATED SURFACE LOW LIFTS TO THE NORTHEAST. SOME LOW LEVEL
MOISTURE LOOKS TO LINGER NEAR THE SOUTHERN END OF THE STATE...WHICH
COULD BRING SOME WETTER THAN NORMAL TRADE WIND SHOWERS TO THE BIG
ISLAND AS A WEAK RIDGE TRIES TO BUILD IN DURING THE EARLY PART OF
THE WEEK. A NEW SYSTEM DEVELOPING NEAR 40N AND THE DATELINE AS WE
HEAD INTO MIDWEEK WILL HELP TO PREVENT THE RIDGE FROM BECOMING TOO
ESTABLISHED.

&&

.MARINE...
THE NORTHWEST SWELL ARRIVING TODAY IS RUNNING JUST A BIT HIGHER THAN
THE WAVE WATCH III GUIDANCE. WITH THAT IN MIND...SOME OF THE
NORTHERN WATERS START THEIR SMALL CRAFT ADVISORY AT NOON TODAY. THE
WATERS NEAR MAUI COUNTY WILL LIKELY SEE SEAS INCREASING TONIGHT. THE
SMALL CRAFT ADVISORY FOR THOSE AREAS WILL LIKELY BE ISSUED THIS
AFTERNOON AS WE SEE THE SWELL MOVE IN TODAY.

HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF NIIHAU AND
KAUAI...AND FOR NORTH FACING SHORES OF OAHU...MOLOKAI...AND MAUI
STARTS AT 4 PM TODAY DUE TO THIS INCOMING SWELL. THE SURF IS
EXPECTED TO PEAK SUNDAY...AND THEN DECREASE SUNDAY NIGHT.

&&

.AVIATION...
AIRMET SIERRA REMAINS UP FOR THE ISLANDS OF MOLOKAI LANAI MAUI AND
THE BIG ISLAND DUE TO MT OBSC AOA 020 DUE TO CLD/SHRA/BR/FG. EXPECT
CONDITIONS TO GRADUALLY IMPROVE OVER MOLOKAI LATER TODAY.

AIRMET TANGO REMAINS UP FOR TURB BTN FL300-FL420 OVER THE ENTIRE
AREA. ALSO EXPECT MOD TO ISOL SEV TURB OVER AND IMT N AND E OF BIG
ISLAND SUMMITS BTN FL100-FL140. ALSO EXPECT SOME MOD TURB N AND E OF
MT HALEAKALA BTN FL080-110.

AIRMET ZULU REMAINS UP FOR LGT-MDT ICE INC AND PCPN LYR FROM
FL120-FL200 OVER THE ISLANDS OF MOLOKAI LANAI MAUI AND THE BIG
ISLAND.

VFR CONDITIONS PREVAIL AT THE TAF SITES THOUGH THERE COULD BE SOME
BRIEF MVFR CONDITIONS IN SHRA/BR.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM HST MONDAY
FOR NIIHAU-KAUAI WINDWARD-KAUAI LEEWARD-OAHU NORTH SHORE-OAHU
KOOLAU-OLOMANA-MOLOKAI-MAUI WINDWARD WEST-MAUI CENTRAL VALLEY-
WINDWARD HALEAKALA.

HIGH WIND WARNING UNTIL 6 PM HST SUNDAY FOR BIG ISLAND SUMMITS.

WINTER WEATHER ADVISORY UNTIL 6 PM HST THIS EVENING FOR BIG
ISLAND SUMMITS.

WIND ADVISORY UNTIL 6 AM HST SUNDAY FOR HALEAKALA SUMMIT.

SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 PM HST SUNDAY FOR
KAUAI NORTHWEST WATERS-KAUAI WINDWARD WATERS-KAUAI LEEWARD
WATERS-KAUAI CHANNEL-OAHU WINDWARD WATERS.
&&

DISCUSSION/MARINE...M BALLARD
AVIATION...BURKE