High Surf in Hawaii, November 2 to 5, 2005

HAWAIIAN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST WED NOV 2 2005

.SYNOPSIS...
A STRONG HIGH PRESSURE SYSTEM NORTH OF THE STATE WILL PROVIDE BREEZY
TRADE WINDS FOR THE NEXT FEW DAYS. SHOWERS WILL FAVOR WINDWARD AND
MAUKA AREAS BUT THE STRONG TRADE WINDS MAY BLOW SOME SHOWERS OVER
LEEWARD AREAS DURING THE LATE NIGHT AND EARLY MORNING HOURS.
&&

.DISCUSSION...
A BLOCKING PATTERN HAS SETUP IN THE UPPER LEVELS ACROSS THE CENTRAL
PACIFIC THIS MORNING. OVER THE MAIN HAWAIIAN ISLANDS A WEAK RIDGE IN
THE UPPER LEVELS CONTINUES TO BRING HIGH CLOUDINESS TO THE ISLANDS.
THE GFS HAS THIS PRETTY WELL IN THE MODEL. THE HIGH CLOUDS ARE
EXPECTED TO FADE BY MID AFTERNOON AS THE UPPER RIDGE FROM THE
BLOCKING PATTERN DRAWS CLOSER. THE CHANGE TODAY FROM THE PAST COUPLE
OF DAYS WILL BE A RETURN TO MOSTLY CLEAR SKIES BY LATE THIS
AFTERNOON. THE ATMOSPHERE ABOVE 800 MB BECOMES VERY DRY AND MID
LEVEL LAPSE RATES SHOW A MORE STABLE LAYER AROUND 800 MB. THEREFORE
THE PATTERN SHOULD BE A VERY TYPICAL TRADE WIND ONE FOR THE NEXT
FEW DAYS WITH MORE CLOUDS AND SHOWERS AT NIGHT MAINLY WINDWARD AND
MAUKA. ON THE SURFACE HIGH PRESSURE CONTINUES TO BUILD INTO THE
REGION THIS SHOULD MAINTAIN THE TRADES AT STRONG LEVELS TODAY.

THE HIGH BEGINS A WEAKENING PROCESS ON THURSDAY INTO THE WEEKEND.
THE TRADES SHOULD SLOWLY WEAKEN THROUGH THE PERIOD. THURSDAY AND
FRIDAY LOOK TO BE MODERATE TRADE DAYS WITHOUT MUCH OUT OF THE
ORDINARY AS THE UPPER LEVEL BLOCKING PATTERN QUICKLY ERODES OVER
THE REGION. LAYERED RELATIVE HUMIDITY REMAINS FAIRLY LOW BEYOND THE
LOWEST LAYERS FOR CONTINUED PARTLY CLOUDY NIGHTS/MOSTLY SUNNY DAYS.

THE WEEKEND REMAINS THE STICKY PART OF THE FORECAST PACKAGE. ALL THE
MODELS HAVE INTRODUCED DIFFERENT SOLUTIONS THE PAST FEW DAYS FOR THE
WEEKEND. THE GFS AND ECMWF HAVE WITH DIFFERENT RUNS DEVELOPED A
VERY STRONG KONA LOW TO THE NORTHEAST OF THE MAIN HAWAIIAN
ISLANDS...HOWEVER IN THE NEXT RUNS THEY BACK OFF FROM IT. THIS 00Z
RUN WITH THE GFS150 AND ECMWF...THE ECMWF DEVELOPS A STRONG KONA LOW
OFF TO THE NORTH OF THE ISLANDS WITH MID LEVEL RIDGING AND AN UPPER
TROUGH ALOFT. THIS SUPPORTS A NORMAL TRADE WIND SOLUTION FOR THE
ISLAND CHAIN. NOW THE GFS150 HAS WEAK TROUGHING ALOFT FOR THE
WEEKEND...AND BRINGS AN INCREASE IN MOISTURE ACROSS THE AREA. OR A
WETTER SOLUTION...NOT A KONA LOW TYPE...BUT MORE SHOWERS COVERAGE
ACROSS THE AREA WITH WEAKER WINDS AND AN INTERIOR CONVECTIVE
PATTERN. ROLL BACK THE CLOCK 24 HOURS AGO AND THE ECMWF WAS WEAKER
WITHOUT A KONA LOW...AND THE GFS150 WAS ALL OVER THE KONA LOW. THE
GOING FORECAST IS MORE OF A CLIMO TREND WHICH IS SUPPORTED BY THE
ECMWF THIS RUN WILL BE FORECAST. WITHOUT A GOOD SIGNALS FROM ANY
MODEL I DON/T FEEL COMFORTABLE MAKING A CHANGE FROM CLIMO IN THE
FORECAST DATABASE AT THIS TIME.

&&

.MARINE...
THE STRONG TRADE WINDS WILL BOOST SHORT PERIOD SURF FOR EAST
FACING SHORES OF ALL ISLANDS. THE WAVEWATCH MODEL SHOWS SEAS
BUILDING TO NEAR 10 FEET ON TODAY. THIS WILL LIKELY CAUSE SURF TO
REACH THE ADVISORY LEVEL OF 8 FEET ON EAST FACING SHORES BY LATER
ON TODAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR ALL HAWAIIAN COASTAL WATERS.
HIGH SURF ADVISORY FOR EAST FACING SHORES OF KAUAI OAHU MOLOKAI MAUI
AND THE BIG ISLAND.
&&

PROTON