983 
FXHW60 PHFO 300658
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST TUE SEP 29 2015

.SYNOPSIS...
A HIGH TO THE NORTH WILL MAINTAIN LOCALLY BREEZY TRADE WINDS FOR
THE NEXT FEW DAYS. THE TRADE WINDS WILL FOCUS SHOWERS OVER MAINLY
WINDWARD AREAS. QUITE A FEW SHOWERS WILL SPREAD LEEWARD TONIGHT AS
THE TRADES PUSH A BAND OF SHOWERY LOW CLOUDS OVER THE ISLANDS. THE
WEATHER WILL DRY OUT A BIT TOMORROW...BUT WINDWARD AREAS WILL
REMAIN RATHER SHOWERY. A DEEP TROUGH ALOFT AND A TROPICAL
DISTURBANCE COULD COMBINE TO PRODUCE WET AND WINDY WEATHER STARTING 
AS EARLY AS SATURDAY. THE UNSETTLED WEATHER COULD CONTINUE FOR 
SEVERAL DAYS.

&&

.DISCUSSION...
SATELLITE LOOPS SHOW AN EAST NORTHEAST TO WEST 
SOUTHWEST BAND OF SHOWERY LOW CLOUDS MOVING OVER THE ISLANDS IN THE 
TRADE-WIND FLOW. THIS CLOUD BAND WILL KEEP WINDWARD AREAS QUITE 
SHOWERY TONIGHT AND LEEWARD AREAS OF THE SMALLER ISLANDS WILL SEE 
SOME SHOWERS AS WELL. 

A 1021 MB SURFACE HIGH ABOUT 850 MILES NORTH NORTHEAST OF OAHU WILL 
MOVE SOUTHEAST AND WEAKEN TO A RIDGE OVER THE NEXT FEW DAYS. HOWEVER 
LOW PRESSURE SOUTH OF THE ISLANDS WILL KEEP THE PRESSURE GRADIENT 
TIGHT ENOUGH TO MAINTAIN LOCALLY BREEZY TRAD WINDS THROUGH FRIDAY. 
SHOWERS CARRIED BY THE TRADE WINDS WILL KEEP WINDWARD AREAS A BIT 
SHOWERY BUT LEEWARD AREAS WILL BE MOSTLY FAIR FROM WEDNESDAY THROUGH 
FRIDAY. 

THE GLOBAL MODELS CONTINUE TO SHOW A TROUGH ALOFT FAR NORTH OF THE 
AREA DIGGING SOUTH RAPIDLY. A SURFACE LOW WILL CUT OFF TO THE 
NORTHEAST OF THE ISLANDS BY FRIDAY AFTERNOON. MEANWHILE...ONE OR 
MORE TROPICAL DISTURBANCES MAY DEVELOP IN AN AREA OF DISTURBED 
WEATHER ASSOCIATED WITH THE MONSOON TROUGH SOUTHWEST OF THE MAIN 
HAWAIIAN ISLANDS ALONG 15N.

THE MODELS SUGGEST THAT THE WINTRY TROUGH TO THE NORTHEAST MAY PULL 
MOISTURE UP OVER THE ISLANDS FROM THE DEEP TROPICS. ONE OR MORE 
TROPICAL CYCLONES COULD EVEN MOVE TOWARD THE ISLANDS FROM THE 
SOUTHWEST. SO...THE WEATHER OVER THE ISLANDS MAY BECOME VERY 
UNSETTLED STARTING AS EARLY AS SATURDAY AND CONTINUING INTO AT LEAST 
THE FIRST HALF OF NEXT WEEK. AT THIS TIME THE DETAILS OF THIS 
COMPLEX PATTERN ARE STILL UNCLEAR.

&&

.AVIATION...
THE LOCALLY STRONG TRADE WINDS WILL CONTINUE TO PRODUCE LOW LEVEL
TURB...SO AIRMET TANGO WILL REMAIN IN EFFECT FOR TURB S THRU W OF
THE MTN OF ALL THE ISLANDS THROUGH AT LEAST TONIGHT AND PROBABLY
LONGER. A BAND OF SHOWERY LOW CLOUDS WILL CONTINUE TO PRODUCE MVFR
CEILINGS AND VSBY IN CLD AND SHRA OVER WINDWARD AREAS THROUGH
TONIGHT. AIRMET SIERRA WILL REMAIN UP R MTN OBSC OVERNIGHT. COND
ARE EXPECTED TO IMPROVE WEDNESDAY AS THE SHOWER BAND CLEARS THE 
ISLANDS.

&&

.MARINE...
A SMALL CRAFT ADVISORY...SCA...REMAINS IN EFFECT FOR ALL WATERS
THROUGH TONIGHT FOR STRONG TRADE WINDS AND ROUGH SEAS. WINDS 
AND SEAS WILL SUBSIDE A BIT OVER THE NEXT COUPLE OF DAYS...BUT THE 
SCA WILL LIKELY STAY UP FOR THE WINDY ZONES AROUND THE BIG ISLAND 
AND MAUI...AND MAY NEED TO STAY UP FOR SOME OTHER AREAS AS WELL.

THE BREEZY TRADES WILL KEEP SURF ELEVATED ALONG EAST FACING SHORES 
THROUGH THE WEEK. A NORTH NORTHEAST SWELL EXPECTED TO ARRIVE FRIDAY 
COULD BRING ADVISORY LEVEL SURF TO NORTH AND EAST FACING SHORES THIS 
WEEKEND.

&&

.HFO WATCHES/WARNINGS/ADVISORIES... SMALL CRAFT ADVISORY UNTIL 600 
AM WEDNESDAY FOR ALL HAWAIIAN WATERS.

&&

$$
DONALDSON