Area Forecast Discussion
Issued by NWS Honolulu, HI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXHW60 PHFO 261928
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST WED NOV 26 2014

.SYNOPSIS...
A RATHER DRY TRADE WIND PATTERN WILL PREVAIL ACROSS MOST OF THE
STATE TODAY...BUT LINGERING LOW LEVEL MOISTURE WILL CONTINUE TO
GENERATE SHOWERS ACROSS WINDWARD PORTIONS OF THE BIG ISLAND. A
STRONG HIGH WILL SETTLE NORTH OF THE ISLANDS STARTING
TONIGHT...DRIVING STRONGER TRADE WINDS FOR THE REST OF THE WEEK AND
INTO THE WEEKEND. CLOUDS AND SHOWERS WILL FAVOR WINDWARD AND MAUKA
AREAS.

&&

.DISCUSSION...
A 1027 MB HIGH NEAR 35N171W...FAR NORTHWEST OF THE MAIN HAWAIIAN
ISLANDS...HAS AN ASSOCIATED RIDGE EXTENDING THROUGH 27N160W AND
27N140W. THE PRESSURE GRADIENT BETWEEN THIS RIDGE AND EQUATORIAL LOW
PRESSURE IS SUFFICIENTLY STEEP TO SUPPORT 15 TO 20 MPH TRADE WINDS
ACROSS MOST LOCAL WATERS. AN OVERNIGHT ASCAT PASS SHOWED STRONGER
WINDS...IN THE 25 TO 30 MPH RANGE...WITHIN THE ALENUIHAHA CHANNEL
AND ACROSS WATERS SOUTH OF THE BIG ISLAND. OVERNIGHT SOUNDINGS SHOW
A STABLE AIRMASS ACROSS THE STATE...WITH CAPE LESS THAN 100 J/KG.
THE MOIST BOUNDARY LAYER NOTED IN THE HILO SOUNDING CORROBORATES THE
LINGERING OVERCAST LOW CLOUDS NOTED ON SATELLITE IMAGERY ACROSS
WINDWARD PORTIONS OF THE EASTERN AND CENTRAL ISLANDS. IN
CONTRAST...THE LIHUE SOUNDING IS QUITE DRY...WITH A PW OF 0.77
INCHES.

WE EXPECT THE CURRENT CLOUD COVER ACROSS WINDWARD AREAS FROM OAHU TO
THE BIG ISLAND WILL DECREASE AS THE DAY WEARS ON. MOST OF THE STATE
SHOULD REMAIN DRY...THANKS TO OUR STABLE AIRMASS AND A GENERAL LACK
OF AVAILABLE MOISTURE. HOWEVER...SCATTERED SHOWERS WILL REMAIN
ACROSS WINDWARD PORTIONS OF THE BIG ISLAND WHERE A BIT MORE MOISTURE
IS AVAILABLE. MODELS SHOW THE HIGH TO OUR NORTHWEST WILL STRENGTHEN
AND MOVE EAST FROM TONIGHT INTO THE WEEKEND...CAUSING LOCAL TRADE
WINDS TO INCREASE INTO THE FRESH TO STRONG CATEGORY. A TRADE WIND
WEATHER PATTERN WILL PERSIST...WITH CLOUDS AND SHOWERS EXPECTED TO
FAVOR WINDWARD AND MAUKA AREAS. WE MAY SEE A MODEST INCREASE IN
WINDWARD SHOWERS ON FRIDAY...WHEN THE REMNANTS OF AN OLD FRONTAL
BOUNDARY REACH THE STATE. ANOTHER WEAK FRONT MAY APPROACH THE STATE
FROM THE NORTHWEST NEXT TUESDAY OR WEDNESDAY.

&&

.AVIATION...
DRY BREEZY TRADES HAVE LEFT MOST OF THE STATE UNDER VFR CONDITIONS.
ONE MAJOR EXCEPTION IS WINDWARD PORTIONS OF THE BIG ISLAND...WHERE
TEMPO MVFR CIGS IN TRADE SHOWERS ARE EXPECTED TO PERSIST THROUGH THE
REMAINDER OF TODAY AND THROUGH TONIGHT. AIRMET SIERRA FOR MTN OBSC
SHOULD REMAIN NECESSARY THROUGH EARLY THURSDAY MORNING.

AIRMET TANGO FOR LOW LEVEL TURBULENCE ON LEE SIDES OF ALL ISLANDS
WILL ALSO LIKELY REMAIN NECESSARY THROUGH THURSDAY MORNING. AN 8000
FT INVERSION ALOFT WILL PERSIST WHILE LOW LEVEL WINDS FURTHER
INTENSIFY THIS AFTERNOON. WINDS WILL REMAIN FRESH AND GUSTY
OVERNIGHT.

&&

.MARINE...
A NORTH NORTHEAST SWELL PEAKING TONIGHT...COMBINED WITH BUILDING
WIND WAVES DUE TO INCREASING TRADE WINDS...WILL CAUSE ROUGH SURF TO
DEVELOP ON EAST FACING SHORES...ESPECIALLY THOSE WITH A NORTHERN
EXPOSURE. NEAR ADVISORY LEVEL SURF MAY OCCUR ACROSS SOME OF THE EAST
FACING SHORES TONIGHT INTO EARLY THURSDAY. THIS SWELL MAY ALSO CAUSE
HARBOR SURGES WITHIN KAHULUI AND HILO HARBORS TONIGHT INTO THURSDAY.

A SMALL CRAFT ADVISORY WILL REMAIN POSTED FOR MOST OF THE MARINE
ZONES DUE TO STRONG WINDS IN THE TYPICALLY WINDY AREAS AROUND MAUI
COUNTY AND THE BIG ISLAND...AND A COMBINATION OF WIND WAVES AND
SWELLS PUSHING COMBINED SEAS TO 10 FEET. ADVISORY CONDITIONS ARE
LIKELY TO REMAIN WIDESPREAD ACROSS THE HAWAIIAN COASTAL WATERS FROM
TONIGHT THROUGH THE REMAINDER OF THIS WEEK AS STRONG TRADE WINDS
CONTINUE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST THURSDAY FOR KAUAI NORTHWEST
WATERS-KAUAI WINDWARD WATERS-KAUAI CHANNEL-OAHU WINDWARD WATERS-
KAIWI CHANNEL-MAUI COUNTY WINDWARD WATERS-MAALAEA BAY-PAILOLO
CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG ISLAND
SOUTHEAST WATERS.

&&

$$

DISCUSSION/MARINE...POWELL
AVIATION...BEDAL









USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.