Weather Service Report


267 
FXHW60 PHFO 292000
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST FRI APR 29 2016

.SYNOPSIS...
A HIGH PRESSURE RIDGE NORTH OF THE ISLANDS WILL MAINTAIN LOCALLY
BREEZY TRADE WINDS THROUGH TONIGHT. EXPECT TRADES TO WEAKEN
SLIGHTLY ON SATURDAY AS A WEAK FRONT PASSES TO THE NORTH OF THE
ISLANDS. A NEW HIGH WILL BUILD NORTH OF THE REGION...BUMPING TRADE
WINDS UP AGAIN FOR THE NEW WEEK. LOOK FOR SHOWERS TO BE FOCUSED
OVER THE WINDWARD SIDES OF THE ISLANDS...WITH AN INCREASE IN
SHOWER ACTIVITY DURING THE MIDDLE OF THE WEEK.

&&

.DISCUSSION...
THE MODELS ARE IN GOOD AGREEMENT WITH THE HANDLING OF THE WEATHER
SITUATION FOR THE FORECAST PERIOD. THE HIGH PRESSURE RIDGE NORTH
OF THE ISLANDS WILL CONTINUE TO BRING LOCALLY BREEZY TRADE WINDS
TO THE ISLANDS THROUGH TONIGHT. A COLD FRONT PASSING FROM WEST TO
EAST NORTH OF THE ISLANDS WILL WEAKEN THE PRESSURE GRADIENT OVER
THE ISLANDS...ALLOWING THE WINDS TO WEAKEN SLIGHTLY ON SATURDAY.
ANOTHER HIGH BUILDS IN BEHIND THE FRONT...MOVING NORTH OF THE
ISLANDS BY SUNDAY AFTERNOON. THIS STRONG HIGH PRESSURE SYSTEM WILL
ONCE AGAIN INCREASE THE PRESSURE GRADIENT OVER THE ISLANDS...SO
EXPECT WINDS TO ONCE AGAIN PICK UP.

MOISTURE FROM THE FRONT PASSING BY THIS WEEKEND IS EXPECTED TO
REACH THE ISLANDS ON THE TRADE WINDS DURING THE MIDDLE OF THE
WEEK. BY WEDNESDAY...THE HIGH WILL BE OFF TO THE NORTHEAST...AS
ANOTHER FRONT WILL APPROACH FROM THE WEST. THERE ARE SOME
DIFFERENCES IN THE MODELS IN THE LONGER TERM FOR THE PLACEMENT OF
THIS FRONT...BUT THE OVERALL FLAVOR SHOWS WINDS NEAR THE ISLANDS
BECOMING A BIT SOUTHEASTERLY ON THURSDAY. THE CURRENT FORECAST
PACKAGE MAINTAINS EASTERLY WINDS THROUGH THE END OF THE WEEK. WILL
BE MAKING SOME MODIFICATIONS TO THE WINDS IN A BIT TO BETTER
REFLECT THIS TREND. THE GFS MODEL BRINGS THIS NEXT FRONT DOWN TO
KAUAI NEXT WEEKEND...WHILE THE ECMWF STARTS TO WASH IS OUT FURTHER
FROM THE ISLANDS. STILL A WAYS OUT...SO WON'T BE MAKING
SIGNIFICANT CHANGES TO THE OTHER FIELDS UNTIL SEEING HOW THIS PANS
OUT.

&&

.AVIATION...
EXPECT MODERATE TO LOCALLY BREEZY TRADE WINDS TO CONTINUE FOR THE
NEXT SEVERAL PERIODS. A FRONT PASSING TO THE NORTH WILL EASE WINDS
ONLY SLIGHTLY LATE TONIGHT INTO SATURDAY BEFORE REBOUNDING SUNDAY.
AIRMET TANGO FOR LOW LEVEL TURB HAS BEEN CANCELLED AS OF
2000Z...THERE HAVE BEEN LIMITED PIREPS SUGGESTING WIDESPREAD
MODERATE LOW LEVEL TURB. HOWEVER...WITH INVERSION HEIGHTS NEAR 7
KFT...WE CAN NOT RULE ISOLATED LIGHT TURB OVER AND IMMEDIATELY SOUTH
THROUGH WEST OF THE MOUNTAINS. 

CLOUDS AND SHOWERS WILL FOCUS ALONG WINDWARD AND MAUKA AREAS.
CONDITIONS SHOULD REMAIN VFR FOR THE MOST PART THROUGH THIS
AFTERNOON...SELECT SHOWERS MAY CARRY BRIEF MVFR CONDITIONS. COOLING
TRENDS THIS EVENING AND TONIGHT WILL LIKELY INCREASE CHANCES FOR
CLOUDS AND SHOWERS ALONG WINDWARD AREAS...SOME AREAS MAY NEED AIRMET
SIERRAS FOR MOUNTAIN OBSC. 

&&

.MARINE...
THE SMALL CRAFT ADVISORY /SCA/ CONTINUES FOR SOME OF THE WINDIER
LOCATIONS. THE SCA MAY BE DROPPED FOR THESE AREAS ON SATURDAY AS
THE WINDS WEAKEN A BIT...BUT THEN AN SCA IS LIKELY GOING TO BE
NEEDED AT LEAST FOR THE TYPICAL WINDER LOCATIONS AS THE NEW WEEK
STARTS. 

THE RESULTANT TRADE WIND SWELL SHOULD DECREASE SLIGHTLY AS WELL ON
SATURDAY...WITH AN INCREASE AGAIN EARLY NEXT WEEK AS THE WINDS
PICK UP AGAIN. SMALL SWELLS FROM THE NORTHWEST WILL CONTINUE
THROUGH THE WEEKEND. SURF ALONG SOUTH FACING SHORES SHOULD
INCREASE SOMEWHAT DURING THE WEEKEND AND INTO EARLY NEXT WEEK AS A
SWELL FROM EAST OF NEW ZEALAND REACHES THE ISLANDS.
OVERALL...EXPECT SURF TO REMAIN BELOW ADVISORY LEVELS ON ALL
SHORES THROUGH THE WEEKEND.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 6 AM HST SATURDAY FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS.


&&

$$

DISCUSSION/MARINE...M BALLARD
AVIATION...EATON

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