High Surf in Hawaii, December 10 to 23, 2012

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
313 PM HST MON DEC 10 2012

.SYNOPSIS...
STRONG AND GUSTY TRADE WINDS WILL IMPACT THE ISLANDS THROUGHOUT
THE WEEK AS HIGH PRESSURE STRENGTHENS TO THE NORTH AND NORTHEAST.
THE WINDS WILL USHER IN A DRIER THAN AVERAGE AIRMASS...WITH
SHOWERS FAVORING WINDWARD AND MAUKA AREAS. AN UPPER-LEVEL LOW MAY
INCREASE SHOWER COVERAGE DURING THE MIDDLE OF THE WEEK.

&&

.DISCUSSION...
STRONG HIGH PRESSURE FAR TO THE NORTH AND NORTHEAST
OF THE STATE WILL DOMINATE OUR WEATHER PATTERN THROUGH THE
REMAINDER OF THE WEEK AND EVEN INTO THE WEEKEND. THE RIDGE IS
BUILDING STRONGLY AND GENERATING A SIGNIFICANT PRESSURE GRADIENT
ACROSS THE AREA. TRADE WINDS HAVE RESPONDED UPWARD INTO THE BREEZY
RANGE IN MANY LOCATIONS. THIS PATTERN WILL GENERALLY REMAIN IN
PLACE WITH ONLY A SLOW DRIFT TO THE SOUTH BY THE RIDGE. WINDS WILL
REMAIN GUSTY THROUGHOUT...WHILE THE PRESSURE GRADIENT REMAINS
ESSENTIALLY INTACT.

SATELLITE IMAGERY AND SOUNDING INFORMATION ARE IN AGREEMENT THAT A
DRY AND STABLE AIRMASS REMAINS UPSTREAM OF THE STATE. THIS AIRMASS
WILL BE ADVECTED OVER THE STATE THROUGHOUT THE REMAINDER OF THE
WEEK. THE REDUCED MOISTURE WILL LIMIT SHOWER ACTIVITY...WITH ANY
SHOWERS THAT FORM FAVORING WINDWARD AND MAUKA AREAS. A WEAK UPPER-
LEVEL FEATURE PASSING OVER THE STATE MID-WEEK MAY ACT TO ENHANCE
SHOWER ACTIVITY TO A SMALL DEGREE...BUT WILL BE LIMITED BY THE
LACK OF MOISTURE.

MID RANGE MODELS ARE IN GOOD AGREEMENT THAT THE RIDGE WILL LINGER
INTO THE WEEKEND...WITH HINTS THAT IT WILL BE REINFORCED EARLY
NEXT WEEK.

&&

.AVIATION...
VFR WILL BE THE PREVAILING CONDITION AT ALL TERMINALS EXCEPT PHTO
THROUGH THE TAF PERIOD. FOR PHTO...EXPECT MVFR CONDITIONS TO
PREVAIL AS SHOWERS AND CLOUDS MOVE IN...MAINLY AT NIGHT AND IN THE
EARLY MORNING HOURS.

AIRMET TANGO REMAINS IN EFFECT FOR MODERATE LOW LEVEL TURBULENCE W
THRU NW OF THE MTN ON ALL ISLANDS...AND THIS WILL REMAIN IN PLACE
FOR THE FORESEEABLE FUTURE. NO OTHER AIRMETS ARE IN EFFECT.

&&

.MARINE...
A LONG FETCH OF STRONG TRADE WINDS WILL LEAD TO INCREASING SHORT PERIOD
EAST SWELL. THE BUILDING SWELL WILL LEAD TO VERY ROUGH AND CHOPPY
CONDITIONS FOR EAST FACING SHORES. WAVE HEIGHTS WILL STEADILY
INCREASE WITH THE ISSUANCE OF A HIGH SURF ADVISORY PRODUCT
LIKELY OVER THE NEXT COUPLE OF DAYS.

THE SMALL CRAFT ADVISORY WILL EXPAND TO ALL COASTAL WATERS BY
EARLY TUESDAY MORNING. WINDS WILL CONTINUE TO BE OVER 25 KNOTS
THROUGH MOST OF THE WEEK.

&&

.FIRE WEATHER...
THE COMBINATION OF STRONG WINDS AND LOW HUMIDITY
USHERED IN A PERIOD OF RED FLAG CONDITIONS FOR PORTIONS OF LEEWARD
AREAS TODAY. CONDITIONS WILL REMAIN IN PLACE FOR A POTENTIAL
REPEAT TUESDAY AFTERNOON. WE WILL BE MONITORING THE CONDITIONS
CLOSELY FOR POTENTIAL ISSUANCE OF ANOTHER WARNING PRODUCT. EVEN IF
RELATIVE HUMIDITY DOES NOT REACH THE 45 PERCENT CRITERIA...WINDS
WILL BE STRONG ENOUGH TO CREATE RAPID FIRE SPREAD IN LEEWARD AREAS
AFFECTED BY DROUGHT CONDITIONS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 6 PM HST THIS EVENING FOR LEEWARD AREAS OF
ALL ISLANDS.

SMALL CRAFT ADVISORY UNTIL 6 AM TUESDAY FOR WATERS NORTHWEST OF
KAUAI...KAUAI/OAHU/MAUI COUNTY/BIG ISLAND WINDWARD WATERS...
CHANNELS BETWEEN THE ISLANDS...MAALAEA BAY...AND WATERS AROUND
SOUTH POINT.

SMALL CRAFT ADVISORY FROM 6 AM TUESDAY TO 6 PM HST THURSDAY FOR
FOR ALL HAWAIIAN WATERS.

&&

DISCUSSION/MARINE/FIRE WEATHER...CANTIN
AVIATION...BRENCHLEY