712 
FXHW60 PHFO 031342
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
338 AM HST MON DEC 3 2012

.SYNOPSIS...
HIGH CLOUDS OVER THE ALOHA STATE WILL DECREASE TODAY AND MOVE EAST 
OF THE AREA BY THIS AFTERNOON. A WEAKENING COLD FRONT JUST TO THE 
NORTHWEST OF THE ISLANDS REMAINS NEARLY STATIONARY AND WILL CONTINUE 
TO BRING PASSING SHOWERS OVER NIIHAU AND KAUAI TODAY. SCATTERED 
SHOWERS MAY DEVELOP OVER THE REST OF THE ISLANDS LATER TODAY WITH 
RAIN IN GENERAL REMAINING LIGHT TO MODERATE. WINDS ARE EXPECTED TO 
DECREASE OR EVEN BECOME LIGHT ACROSS MUCH OF THE AREA LATER THIS 
AFTERNOON. ANOTHER COLD FRONT APPROACHES KAUAI FROM THE NORTHWEST ON 
TUESDAY AND BRINGS INCREASING SHOWERS...MAINLY WEST OF MAUI COUNTY 
THROUGH LATE WEDNESDAY. LIGHT TRADES ARE THEN EXPECTED TO RETURN FOR 
THE END OF THE WORK WEEK. 

&&

.DISCUSSION...
A DECAYING FRONTAL BOUNDARY REMAINS NEARLY STATIONARY JUST NW OF 
KAUAI WITH A NARROW BAND OF MOSTLY LIGHT RAIN STILL AFFECTING KAUAI 
AND NIIHAU THROUGH THIS MORNING. THE FRONT WILL SLOWLY PUSH 
EASTWARD...BUT IT WILL WEAKEN EVEN FURTHER OR MAY EVEN DISSIPATE OR 
LIFT NORTH BEFORE REACHING OAHU. SFC RIDGING EAST OF THE STATE IS 
STILL EXTENDING INTO THE BIG ISLAND AND MAUI COUNTY...AND SHOULD 
REMAIN IN PLACE DURING THE NEXT COUPLE OF DAYS.   

MEANWHILE...AN UPPER LVL TROUGH EXTENDS SOUTH OF AN UPPER LOW NEAR 
170W. THIS SYSTEM IS RESPONSIBLE FOR THE PERSISTING SW WINDS ALOFT 
AND THE MID/UPPER LVL CLOUD COVER THAT HAS KEPT MUCH OF THE AREA 
UNDER CLOUDY CONDITIONS THE LAST FEW DAYS. BUT THE CLOUD COVERAGE 
SHOULD GRADUALLY DECREASE TODAY AS THE FLOW ALOFT SWITCHES TO THE 
WEST AND PUSHES THE MAIN CANOPY OF CLOUDS FURTHER TO THE EAST OF THE 
ISLANDS. LATEST IR/WV IMAGERY IS INDEED SHOWING THE EDGE OF THE 
THICKER CLOUDS NOW PUSHING EAST OF MAUI COUNTY...AND THIS TREND 
SHOULD CONTINUE TODAY.  

THE REMAINING SHOWERS IN THE AREA WILL MOSTLY AFFECT NIIHAU AND 
KAUAI THROUGH THE MORNING HOURS. ELSEWHERE...ENOUGH MOISTURE WILL 
LINGER OVER THE AREA FOR SOME SCATTERED SHOWERS TO DEVELOP THROUGH 
THE DAY. RAIN IN GENERAL SHOULD REMAIN LIGHT TO MODERATE. THE STRONG 
SW FLOW ALOFT IS KEEPING WIND ADVISORY LEVELS AT THE MOUNTAIN 
SUMMITS UNTIL 6 AM HST THIS MORNING.   

THE SFC RIDGE OVER THE EASTERN PORTIONS OF THE ALOHA STATE IS 
TRYING TO SLOWLY PUSH NORTHWARD THROUGH TUESDAY WHILE THE TROUGH 
ALOFT TO THE WEST WILL LIFT OUT TO THE NE. LATEST MODEL RUNS DEVELOP 
A SECOND UPPER LVL TROUGH AROUND 170W ON TUESDAY...BRINGING BACK 
STRONG SW WINDS ALOFT AND INCREASING HIGH CLOUD COVER AGAIN ACROSS 
THE MAIN HAWAIIAN ISLANDS. AN ASSOCIATED FRONTAL BOUNDARY APPROACHES 
KAUAI FROM THE NW ALSO ON TUESDAY AS A COUPLE OF CLOSED LOWS ROTATE 
AROUND THE AFOREMENTIONED TROUGH. RAIN CHANCES WILL AGAIN INCREASE 
TUE THROUGH WED...BUT THE AIRMASS OVER THE AREA SEEMS TO REMAIN 
STABLE ENOUGH TO KEEP CHANCES OF THUNDERSTORM ACTIVITY LOW. 
HOWEVER...THE SITUATION WILL BE CLOSELY MONITORED IN CASE CONDITIONS 
CHANGE SIGNIFICANTLY IN UPCOMING MODEL GUIDANCE. 

FOR THE SECOND HALF OF THE WORK WEEK...LIGHT TRADE WINDS AND 
GENERALLY PARTLY CLOUDY SKIES SHOULD RETURN ACROSS MUCH OF THE AREA 
WITH LOW CLOUDS AND SHOWERS FAVORING WINDWARD AND MAUKA SECTIONS. 
THEN MODELS SUGGEST THE POSSIBLE ARRIVAL OF ANOTHER FRONTAL BOUNDARY 
FROM THE NORTHWEST DURING THE WEEKEND. 

&&

.MARINE...
A LARGE NORTHWEST SWELL WILL KEEP HIGH SURF CONDITIONS THROUGH LATER 
THIS AFTERNOON...THUS A HIGH SURF ADVISORY  REMAINS IN EFFECT FOR 
NORTH AND WEST FACING SHORES OF NIIHAU KAUAI AND MOLOKAI...AND NORTH 
FACING SHORES OF OAHU UNTIL 6 PM HST TODAY.  

ALSO...A SMALL CRAFT ADVISORY IS IN EFFECT FOR ALL KAUAI WATERS...
INCLUDING KAUAI CHANNEL...UNTIL 6 PM HST TODAY. CONDITIONS SHOULD 
THEN BEGIN SUBSIDING ON THIS EVENING. 

&&

.AVIATION...
SOME OF THE TAF SITES ARE REPORTING MVFR/IFR CIGS THIS MORNING... 
WITH LIFR CIGS RECENTLY REPORTED AT PHNY...WITH THE LOW CLOUD BASES 
DUE TO A SATURATED AIR MASS. LOW CLOUD BASES ARE EXPECTED TO RISE 
AFTER SUNRISE THIS MORNING...WITH ONLY ISOLATED MVFR CIG/VIS 
EXPECTED THEREAFTER. THIS WILL MAINLY BE NEAR KAUAI...WHERE A NE-SW 
ORIENTED BAND OF SHRA WILL PERSIST BEFORE GRADUALLY WEAKENING LATER 
TODAY.  

AIRMET TANGO REMAINS IN EFFECT FOR MOD TURB BLW 150 TO THE N AND E 
OF THE MTN OF ISLANDS FROM MAUI TO KAUAI AS LATEST RADAR VAD WIND 
PROFILES INDICATE WSW WINDS UP TO 30 KT IN THE LOWER LEVELS. 
GUIDANCE SHOWS THESE WINDS DIMINISHING BY LATE TODAY. 

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 PM HST TODAY FOR NIIHAU-KAUAI 
WINDWARD-KAUAI LEEWARD-OAHU NORTH SHORE-OAHU KOOLAU-MOLOKAI.

WIND ADVISORY UNTIL 10 AM HST MONDAY FOR HALEAKALA SUMMIT-BIG 
ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST MONDAY FOR KAUAI NORTHWEST 
WATERS-KAUAI WINDWARD WATERS-KAUAI LEEWARD WATERS-KAUAI CHANNEL.

&&

$$

DISCUSSION/MARINE...REYNES
AVIATION...BIRCHARD