FXHW60 PHFO 080554
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST MON DEC 7 2009

.SYNOPSIS...
A FEW CLOUDS AROUND MAUI COUNTY AND OAHU WILL DISSIPATE AS WEAK 
TRADES RETURN BY WEDNESDAY. THE TRADES WILL DIMINISH FURTHER BY 
FRIDAY...AND THEN TURN INTO SOUTHEASTERLIES AS ANOTHER FRONT 
APPROACHES THE STATE OVER THE WEEKEND.

&&

.DISCUSSION...
A CLOUD BAND ASSOCIATED WITH A WEAKENING COLD FRONT DISSIPATED 
SLOWLY AROUND MAUI COUNTY AND OAHU...PRODUCING LITTLE OR NO RAIN. 
THE SOUTHEASTWARD PROGRESS OF THIS FEATURE SLOWED TO A CRAWL...SO IT 
MAY NOT EVEN REACH THE BIG ISLAND BEFORE DISINTEGRATING COMPLETELY. 
SURFACE OBSERVATIONS ACROSS THE STATE REPORTED MOSTLY MODEST 
NORTHERLY WINDS...AND PRESSURE TRENDS SUGGESTED A CONTINUED 
TRANSITION TO MODERATE TRADES. PRE-FRONTAL CONVERGENCE STILL 
SUPPORTED A STRATUS BAND SOUTH OF AND PARALLEL TO THE MAIN FRONTAL 
BAND. WHILE THIS SECONDARY FEATURE HAD DRIFTED SOUTHEAST OF THE 
STATE...SOME FRAGMENTS STILL LINGERED ALONG THE EAST COAST OF THE 
BIG ISLAND...AND THE BAND MAY REBUILD TOWARD THE NORTHWEST AGAIN 
AFTER SUNSET. MEASUREMENTS FROM THE OBSERVATORIES ON MAUNA KEA 
CONTINUED TO REPORT DRY CONDITIONS...AND THE LOWERED INVERSION 
HEIGHT ON THE HILO SOUNDING SHOWED SOME SHALLOWING OF THE SURFACE 
MIXED LAYER...THOUGH LESS THAN AT LIHUE. ALOFT...A SHELF OF BROAD 
AND FLAT RIDGING OVER THE CENTRAL NORTH PACIFIC KEPT THE MORE 
EXTREME ACTIVITY WELL NORTH OF THE STATE...THOUGH OVERALL THE NORTH 
PACIFIC DISPLAYED A PROGRESSIVE PATTERN OF FAST-MOVING LONG WAVES.

GUIDANCE GENERALLY AGREES THAT THE SUBTROPICAL RIDGE WILL REBUILD 
QUICKLY AS THE FRONT DISSIPATES...BRINGING TRADES BACK TO THE 
ISLANDS BY WEDNESDAY MORNING...BUT THE RIDGE WILL BE DISPLACED SOUTH 
AGAIN BY THURSDAY UNDER THE INFLUENCE OF ANOTHER APPROACHING 
FRONT...KEEPING THE TRADES LIGHT LOCALLY. THIS SECOND FRONT IS 
EXPECTED TO DISSIPATE NORTH OF THE STATE AROUND FRIDAY MORNING... 
THUS LIMITING ITS EFFECT ON THE ISLANDS TO A PERIOD OF SLACK WINDS 
FROM THURSDAY NIGHT INTO FRIDAY. GUIDANCE PREDICTS A THIRD... 
STRONGER FRONT TO TURN THE WEAK TRADES AROUND INTO SOUTHEASTERLIES 
OVER THE WEEKEND...AND THEN TO REACH KAUAI ON SUNDAY NIGHT. THIS 
THIRD FRONT IS LIKELY TO BRING MORE RAINFALL THAN DID THE ONE 
AFFECTING THE STATE SUNDAY NIGHT AND THIS MORNING...BUT ACCUMULATION 
STILL PROBABLY WILL NOT PROVE HEAVY ENOUGH TO POSE SIGNIFICANT 
PROBLEMS.

&&

.MARINE...
DANGEROUS AND POSSIBLY DESTRUCTIVE SURF IS EXPECTED TO CONTINUE ON 
SHORES FACING NORTHWEST. THE CURRENT FORECAST SURF HEIGHTS LOOK 
GOOD. THE HIGH SURF WARNING AND SMALL CRAFT ADVISORY WILL REMAIN IN 
EFFECT.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF WARNING UNTIL 6 PM HST WEDNESDAY FOR NIIHAU-KAUAI 
WINDWARD-KAUAI LEEWARD-WAIANAE COAST-OAHU NORTH SHORE-OAHU 
KOOLAU-OLOMANA-MOLOKAI-MAUI WINDWARD WEST-MAUI LEEWARD WEST-MAUI 
CENTRAL VALLEY-WINDWARD HALEAKALA-KONA-BIG ISLAND NORTH AND EAST-
KOHALA.

SMALL CRAFT ADVISORY UNTIL 6 PM HST WEDNESDAY FOR KAUAI 
NORTHWEST WATERS-KAUAI WINDWARD WATERS-KAUAI LEEWARD WATERS-
KAUAI CHANNEL-OAHU WINDWARD WATERS-OAHU LEEWARD WATERS-KAIWI 
CHANNEL-MAUI COUNTY WINDWARD WATERS-MAUI COUNTY LEEWARD WATERS-
ALENUIHAHA CHANNEL-BIG ISLAND WINDWARD WATERS-BIG ISLAND LEEWARD 
WATERS-BIG ISLAND SOUTHEAST WATERS.

&&

$$

RYSHKO