Weather Service Report


336 
FXHW60 PHFO 250630
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST FRI OCT 24 2014

.SYNOPSIS...
LIGHT TO MODERATE TRADES CONTINUE TONIGHT AND THROUGH THE REST OF 
THE WEEKEND WITH SHOWERS FAVORING WINDWARD AND MAUKA AREAS. SOME OF 
THE LARGER SHOWERS WILL REACH LEEWARD LOCATIONS AT TIMES...INCLUDING 
THE HONOLULU METRO AREA. SHOWERS MAY INCREASE LATE SATURDAY AND 
EARLY SUNDAY AS A WEAK FRONT REACHES THE ISLANDS FROM THE NORTH. 
STABLE MODERATE TRADES ARE EXPECTED THROUGH EARLY NEXT WEEK...THEN 
STRONGER TRADES ARE POSSIBLE FOR THE LATER PART OF THE WORK WEEK. 

&&

.DISCUSSION...
A STRONG SFC HIGH PRESSURE SYSTEM REMAINS FAR NNE OF THE MAIN 
HAWAIIAN ISLANDS AND KEEPING A TRADE WIND WEATHER REGIME IN PLACE 
TONIGHT. RATHER ABUNDANT LOW LEVEL MOISTURE WILL KEEP FEEDING TRADE 
WIND SHOWERS...MAINLY FOCUSING OVER WINDWARD AND MOUNTAIN AREAS. 
BUT SOME OF THE LARGER SHOWERS WILL REACH LEEWARD LOCATIONS AT 
TIMES...INCLUDING THE HONOLULU METRO AREA THIS EVENING AND THROUGH 
THE OVERNIGHT HOURS. 

SATELLITE IMAGERY AND MODEL DATA DEPICT A BAND OF CLOUDS AND SHOWERS 
ASSOCIATED WITH A WEAKENING FRONTAL BOUNDARY N OF THE ISLANDS MOVING 
TOWARDS THE AREA...LOCATED ABOUT 250 MILES NE OF MAUI. MEANWHILE...A 
WEAKER BAND OF SHOWERS BETWEEN THE ISLANDS AND THE FRONTAL BOUNDARY 
IS ALSO SLOWLY DRIFTING INTO THE AREA. BOTH THESE FEATURES WILL 
COMBINE TO KEEP A RELATIVELY ACTIVE TRADE WIND SHOWER PATTERN IN 
PLACE THROUGH THE WEEKEND. BEST POTENTIAL FOR SHOWERS IS EXPECTED 
SAT EVENING THROUGH EARLY SUN WHEN THE LARGER FRONTAL BAND REACHES 
THE ISLANDS. HOWEVER...MODELS REMAIN CONSISTENT IN KEEPING HIGH 
PRESSURE ALOFT OVER THE AREA DURING THE NEXT SEVERAL DAYS...WHICH 
SHOULD LIMIT SOMEWHAT RAINFALL COVERAGE. NEVERTHELESS....EXPECT 
LIGHT TO MODERATE TRADES WITH PASSING SHOWERS TO CONTINUE THROUGH 
EARLY NEXT WEEK WITH BEST CHANCES FOR HEAVIER RAIN OVER WINDWARD AND 
MAUKA AREAS.

MODELS SHOW THE HIGH PRESSURE FAR NNE OF THE ISLANDS STRENGTHENING 
AGAIN DURING THE SECOND HALF OF NEXT WEEK AS A DEEP TROUGH FAR NW OF 
THE AREA LIFTS OUT. THIS MAY ALLOW FOR THE HIGH TO INTENSIFY...
BRINGING STRONGER PRESSURE GRADIENTS ACROSS THE ISLAND CHAIN. 
THUS...POTENTIALLY STRONGER TRADES COULD BE IN STORE FOR THE LATER 
PART OF NEXT WEEK. 

&&

.AVIATION...
NO AIRMETS ARE IN EFFECT THIS EVENING. PASSING TRADE WIND CLOUDS 
AND SHOWERS...IMPACTING WINDWARD AND MAUKA AREAS...WILL PROVIDE 
ISOLATED MVFR CEILINGS TONIGHT AND SATURDAY MORNING. LEEWARD AREAS 
SHOULD REMAIN VFR.

&&

.MARINE...
SMALL SOUTHERLY AND NORTHWESTERLY SWELLS WILL DECREASE OVER THE NEXT 
FEW DAYS. EXPECTING A MODERATE NORTHERLY SWELL FOR THE SECOND HALF 
OF NEXT WEEK. 

LARGE SCALE TRADE WINDS ARE EXPECTED TO REMAIN IN THE LIGHT TO 
MODERATE CATEGORY WHICH MEANS LOCALLY FRESH TRADES IN THE 
WINDIER CHANNELS THROUGH THE MIDDLE OF NEXT WEEK.  TRADE WINDS ARE 
EXPECTED TO INCREASE DRAMATICALLY THURSDAY AND FRIDAY OF NEXT WEEK 
AS A STRONG HIGH BUILDS IN TO THE NORTH.

&&

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

&&

$$

REYNES



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