Weather Service Report


248 
FXHW60 PHFO 230630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST MON SEP 22 2014

.SYNOPSIS...
RETURNING TRADE WINDS WILL SHIFT CLOUD COVER AND SHOWER ACTIVITY 
OVER WINDWARD AND MOUNTAIN AREAS DURING THE NEXT COUPLE OF DAYS. 
LEEWARD AREAS WILL REMAIN RATHER DRY...EXCEPT FOR AFTERNOON SHOWERS 
DEVELOPING OVER THE KONA COAST. THE TRADES ARE ALSO BRINGING A 
RELIEF FROM THE MUGGY AND HUMID CONDITIONS FORM THE PAST SEVERAL 
DAYS. A WET TRADE WIND PATTERN IS EXPECTED TO DEVELOP STARTING LATE 
WEDNESDAY AND INTO THURSDAY...AND POSSIBLY PERSISTING THROUGH THE 
UPCOMING WEEKEND.

&&

.DISCUSSION...
THE TRADES ARE FINALLY MAKING A COMEBACK WITH SPEEDS GRADUALLY 
BECOMING MODERATE DURING THE NEXT COUPLE OF DAYS AND PERSISTING 
THROUGH THE WEEKEND. THIS IS MAINLY DUE TO A STRENGTHENING SFC HIGH 
FAR NW OF THE ALOHA STATE...WHICH IS BRINGING TIGHTER PRESSURE 
GRADIENTS ACROSS THE AREA. SLIGHTLY STRONGER TRADES WILL BUILD ON 
TUE...THEN RELAX A LITTLE ON WED AS THE HIGH SLOWLY MIGRATES E 
DURING THE NEXT SEVERAL DAYS. 

THE TRADES ARE ALSO PROVIDING FOR A MUCH ANTICIPATED RELIEF FROM 
THE MUGGY AND HUMID CONDITIONS FROM LAST WEEK. LATEST MIMIC/MODEL 
MOISTURE ANALYSES DEPICT A DRIER AIRMASS MOVING INTO THE AREA WITH
DEW POINTS A FEW DEGREES LOWER FROM THE VALUES EXPERIENCED DURING 
THE PAST SEVERAL DAYS. TEMPERATURES WILL ALSO COOL DOWN A 
LITTLE...BUT LEEWARD AREAS WILL LIKELY REMAIN SEASONABLY HOT 
HOVERING THE 90 DEGREE MARK THROUGH THE NEXT COUPLE OF DAYS.  

THROUGH MID WEEK...SHOWER ACTIVITY WILL SHIFT TO WINDWARD AND 
MOUNTAIN AREAS...AS WELL AS AFTERNOON PERIODS OF CLOUDS AND SHOWERS 
OVER THE KONA SLOPES. RAINFALL ACCUMULATIONS IN GENERAL SHOULD 
REMAIN LIGHT.  

MODELS DEPICT A RATHER WETTER SCENARIO FOR THE SECOND HALF OF THE 
WEEK AS THE AFOREMENTIONED HIGH MOVES TO THE N OF THE ISLAND CHAIN 
AND PUSHES A REMNANT BAND OF MOISTURE FROM A FORMER FRONTAL BOUNDARY 
TOWARD THE AREA. THIS WILL BRING AN INCREASE IN TRADE SHOWERS 
STARTING WED NIGHT AND LASTING PROBABLY THROUGH THE WEEKEND. THIS 
ENHANCED MOISTURE WILL PROVIDE FOR AN ACTIVE RAIN PATTERN ESPECIALLY 
OVER WINDWARD AND MOUNTAIN AREAS...WITH SOME OF THE LARGER SHOWERS 
REACHING LEEWARD LOCATIONS AT TIMES INCLUDING THE HONOLULU METRO 
AREA. MEANWHILE...MODELS ALSO SHOW A MID/UPPER LEVEL TROUGH MOVING 
NEAR THE ISLAND CHAIN FROM THE SE ON THE FRI-SAT TIMEFRAME...WHICH 
COULD FURTHER ENERGIZE THE BAND OF MOISTURE AND BRING THE POTENTIAL 
FOR PERIODS OF LOCALIZED HEAVY RAIN. 

SINCE THE OVERALL SCENARIO IS STILL BEING EVALUATED...THE FORECAST 
WILL CONTINUE TO CARRY HIGHER POPS FOR THE LATER PART OF THE WEEK 
BUT WITH NO MENTION OF HEAVY RAINFALL ATTM. THE DETAILS WILL BECOME 
CLEARER OVER THE NEXT COUPLE OF DAYS.

&&

.AVIATION...
TRADE WINDS WILL CONTINUE TO GRADUALLY STRENGTHEN THROUGH TUESDAY. 
CLOUDS AND SHOWERS WILL BE FOCUSED PRIMARILY ACROSS WINDWARD AND 
MAUKA AREAS...WITH BRIEF MVFR CONDITIONS OCCURRING IN SHOWERS. AN 
AIRMET FOR LOW LEVEL TURBULENCE TO THE LEE OF HIGHER TERRAIN MAY 
BECOME NECESSARY LATER TONIGHT OR TUESDAY MORNING AS THE TRADES
INCREASE.

&&

.MARINE...
TRADES WILL BE CLOSE TO SMALL CRAFT ADVISORY LEVELS ACROSS 
THE TYPICALLY WINDIER WATERS AROUND THE BIG ISLAND AND MAUI COUNTY 
THROUGH AT LEAST FRIDAY. WINDS MAY BRIEFLY INCREASE A LITTLE OVER 
THE NORTHERN HALF OF THE ISLAND CHAIN AS A BAND OF MOISTURE MOVES 
INTO THE CENTRAL PORTIONS OF THE ALOHA STATE ON THURSDAY.

SURF WILL REMAIN AROUND BACKGROUND LEVELS THROUGH MUCH OF THE WEEK. 
A SLIGHTLY HIGHER SWELL...POSSIBLY UP TO 4 FEET...IS EXPECTED FROM 
THE NNE THURSDAY THROUGH SATURDAY. A MODERATE SSW IS ALSO EXPECTED 
TO ARRIVE THIS WEEKEND.

&&

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

&&

$$

DISCUSSION/MARINE...REYNES
AVIATION...JACOBSON




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