High Surf Advisory 8, NWS Honolulu, HI

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST FRI JAN 27 2012

.UPDATE...
WE HAVE UPDATED THE FORECASTS TO ADJUST THE PROBABILITY OF
PRECIPITATION...WEATHER AND CLOUD COVER.

&&

.SYNOPSIS...
MOISTURE FROM A DISSIPATING FRONT WILL PRODUCE CLOUDS AND SHOWERS
OVER INTERIOR AREAS THIS AFTERNOON AND EVENING. LIGHT WINDS WILL
KEEP THE AIR HAZY THROUGH TONIGHT. A SURFACE RIDGE WILL BUILD NORTH
OF THE ISLANDS OVERNIGHT...BRINGING TRADE WINDS BY TOMORROW. THE
TRADES WILL PERSIST THROUGH NEXT WEEK.

&&

.PREV DISCUSSION 1000 AM...
A WEAK NORTHEAST TO SOUTHWEST TROUGH...THE REMNANT OF A FRONT...
RUNS ACROSS THE KAUAI CHANNEL AND AN EAST WEST SURFACE RIDGE LIES
JUST NORTH OF KAUAI. THESE FEATURES WILL PRODUCE GENTLE TO MODERATE
SOUTHEAST TRADE WINDS NEAR THE BIG ISLAND...AND LIGHT AND VARIABLE
WINDS ELSEWHERE AROUND THE MAIN HAWAIIAN ISLANDS TODAY. A CLOUD BAND
ASSOCIATED WITH THE FRONT RUNS NORTHEAST TO SOUTHEAST ACROSS THE
ISLANDS NEAR...BUT THERE IS A BREAK IN THE BAND WHERE IT CROSSES THE
ISLANDS. THE SOUTHEAST FLOW NEAR THE BIG ISLAND IS CARRYING SHOWERS
ONSHORE ALONG THE SOUTHEAST COAST OF THAT ISLAND. LAND BREEZES
CLEARED THE SHOWERS FROM THE REST OF THE LAND AREAS LAST NIGHT BUT
SHOWERS LINGER OVER WATERS NORTHEAST AND SOUTHWEST OF OAHU.

WITH THE LIGHT WINDS AROUND THE ISLANDS...IT WILL REMAIN HAZY
TODAY. AS THE ISLANDS HEAT UP TODAY...CLOUDS WILL BUILD OVER THE
ISLANDS AND SHOWERS WILL DEVELOP...ESPECIALLY OVER INTERIOR AREAS...
AND SOME OF THE SHOWERS COULD BE BRIEFLY HEAVY. THE SHOWER ACTIVITY
WILL SUBSIDE THIS EVENING.

THE COMPUTER MODELS ARE IN GOOD AGREEMENT SHOWING THE SURFACE RIDGE
BUILDING NORTH OVERNIGHT. AS THE RIDGE BUILDS...TRADE WINDS WILL
RETURN. THE TRADE WINDS WILL CONTINUE THROUGH THE WEEK. THE PRESSURE
GRADIENT WILL BE TIGHT ENOUGH TO PRODUCE LOCALLY BREEZY TRADES
THROUGH MONDAY. THE TRADES MAY EVEN BE STRONG ENOUGH TO REQUIRE A
WIND ADVISORY FOR THE VOLCANO SUMMITS STARTING TOMORROW. THE TRADES
WILL TAPER OFF ON MONDAY...BUT MAY BECOME BREEZY AGAIN WEDNESDAY
THROUGH FRIDAY AS THE PRESSURE GRADIENT TIGHTENS AGAIN.

MEANWHILE...THE TROUGH ALOFT THAT HAS BEEN MAKING THE ATMOSPHERE
OVER THE ISLANDS SOMEWHAT UNSTABLE WILL MOVE AWAY TO THE NORTHEAST.
A RIDGE WILL BUILD OVER THE ISLANDS FROM THE SOUTHWEST AND THE
ATMOSPHERE WILL BECOME QUITE STABLE STARTING TOMORROW. THE TRADE
WINDS WILL CARRY SOME SHOWERS OVER WINDWARD AREAS STARTING TOMORROW
BUT THE STABLE ATMOSPHERE WILL KEEP RAINFALL LIGHT.

&&

.AVIATION...
THERE ARE NO AIRMETS UP AT THIS TIME BUT AFTERNOON CONVECTION COULD
PRODUCE ENOUGH LOW CEILINGS AND VISIBILITIES TO REQUIRE AN AIRMET
FOR MOUNTAIN OBSCURATION LATER TODAY. STRENGTHENING TRADE WINDS WILL
LIKELY REQUIRE AN AIRMET FOR LOW LEVEL TURBULENCE BY SATURDAY NIGHT.

&&

.MARINE...
SURF WILL BUILD ABOVE THE ADVISORY LEVEL BY EARLY SATURDAY MORNING
ON KAUAI AND COULD REACH NEAR 20 FEET SATURDAY AFTERNOON. A HIGH
SURF ADVISORY WILL LIKELY BE ISSUED THIS AFTERNOON. A LARGER
NORTHWEST SWELL MAY PRODUCE WARNING LEVEL SURF ON MONDAY FOR NORTH
AND WEST SHORES.

SMALL CRAFT ADVISORIES WILL LIKELY BE NEEDED FOR COMBINED SEAS AND
WINDS SATURDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

DONALDSON