High Surf Advisory 1, NWS Honolulu, HI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST MON JAN 1 2007

.SYNOPSIS...EXCEPT FOR A FEW SHOWERS OVER MOUNTAIN AREAS AND ALONG
THE WINDWARD BIG ISLAND...THE STATE WILL ENJOY MOSTLY DRY WEATHER
THROUGH TONIGHT. TRADE WINDS WILL BE LIGHT TODAY AND TUESDAY...BUT
WILL INCREASE WEDNESDAY AS A STRONG HIGH PASSES TO THE NORTH OF THE
STATE. ALSO...EXPECT AN INCREASE IN TRADE WIND SHOWERS FROM LATE
TUESDAY THROUGH FRIDAY.

&&

.DISCUSSION...THE FIRST DAY OF THE NEW YEAR WILL CONTINUE TO HAVE
MINIMAL SHOWER ACTIVITY OVER MOST AREAS OF THE ALOHA STATE THROUGH
TONIGHT. THOSE SHOWERS THAT DO OCCUR WILL MAINLY BE ALONG THE
WINDWARD SLOPES...AS WELL AS THE WINDWARD AND SOUTHEASTERN COASTAL
SECTIONS OF THE BIG ISLAND.

THE ISLANDS ARE BETWEEN AN UPPER TROPOSPHERIC RIDGE TO THE NORTH AND
AN UPPER TROPOSPHERIC LOW LOCATED ABOUT 650 MILES SOUTHEAST OF HILO.
THE GRADIENT BETWEEN THESE FEATURES CONTINUES TO PRODUCE STRONG
EASTERLY WINDS ACROSS THE SUMMITS ON MAUI AND THE BIG ISLAND. A WIND
ADVISORY REMAINS POSTED FOR HALEAKALA AND THE BIG ISLAND SUMMITS. IT
IS EXPECTED THERE WILL BE A DECREASE IN THE UPPER LEVEL WIND SPEEDS
BY TUESDAY MORNING.

THE UPPER TROPOSPHERIC LOW SOUTHEAST OF THE BIG ISLAND IS MOVING
WESTWARD AT ABOUT 10 MPH. BROKEN TO OVERCAST MULTI-LAYERED CLOUDS
WITH EMBEDDED ISOLATED THUNDERSTORMS ARE WITHIN 600 MILES EAST AND
SOUTHEAST OF THIS LOW ALOFT. AS THIS LOW MOVES WESTWARD...EXPECT
MIDDLE AND HIGH LEVEL CLOUDS TO SPREAD UP FROM THE SOUTHEAST OVER
THE BIG ISLAND TUESDAY. THE MOISTURE THAT SPREADS UP THE ISLAND
CHAIN IS NOT EXPECTED TO BE EXCESSIVE.

ON WEDNESDAY...A COLD FRONT WILL APPROACH KAUAI FROM THE NORTHWEST.
THIS FRONT IS EXPECTED TO RAPIDLY TRANSFORM TO A SHEAR LINE.
HOWEVER...THIS SHEAR LINE IS NOT EXPECTED TO REACH THE ISLANDS DUE
TO THE LACK OF UPPER LEVEL SUPPORT. BY WEDNESDAY AFTERNOON...THE
MODELS INDICATE A 1035 MB SURFACE HIGH WILL BE LOCATED ABOUT 1050
MILES NORTH OF HONOLULU. THIS WILL RESULT IN A SIGNIFICANT INCREASE
IN THE TRADE WINDS FROM WEDNESDAY INTO FRIDAY.

EXPECT AN INCREASE IN WINDWARD SHOWERS FROM LATE TUESDAY THROUGH
FRIDAY. ALTHOUGH THE PRECIPITATION IS EXPECTED PRIMARILY IN THE
USUALLY WET WINDWARD AND MOUNTAIN AREAS. CONDITIONS OVERALL WILL BE
RATHER BLUSTERY WITH THE ADDED STRONG TRADE WINDS BLOWING SOME OF
THE SHOWERS OVER TO THE LEEWARD PARTS OF THE ISLANDS.

TRADES WILL SLOWLY WEAKEN AGAIN BY FRIDAY NIGHT AND SATURDAY...SINCE
THE THE SURFACE HIGH WILL HAVE MOVED FARTHER EAST. THE MODELS
INDICATE THE ASSOCIATED SURFACE RIDGE TO OUR NORTH WILL ALSO WEAKEN
THIS WEEKEND. THE LONG RANGE SCENARIO DEPICTS A LARGE SURFACE TROUGH
FORMING WEST OF KAUAI BY NEXT MONDAY. IF THIS OCCURS...THERE MAY BE
A SIGNIFICANT CHANGE IN THE SYNOPTIC PATTERN...AND OUR LOCAL WEATHER
CONDITIONS...EARLY NEXT WEEK.

&&

.MARINE...
THE VERY LARGE WEST-NORTHWEST SWELL ARRIVING TONIGHT IS EXPECTED TO
PRODUCE SURF HEIGHTS AT OR ABOVE THE HIGH SURF WARNING THRESHOLD
ALONG NORTH AND WEST FACING SHORES OF THE SMALLER ISLANDS FROM KAUAI
TO MAUI...EXCLUDING LANAI...BY TUESDAY MORNING. THEREFORE...EXPECT
HIGH SURF WARNINGS/ADVISORIES TO BE ISSUED THIS AFTERNOON. ON THE
LEEWARD BIG ISLAND...WAVE WATCH III MODEL INDICATES THAT THE SWELL
WILL BE FROM ABOUT 300 DEGREES. THIS WILL LIKELY RESULT IN SURF
HEIGHTS ABOVE THE HIGH SURF WARNING THRESHOLD OF 12 FEET FOR
PORTIONS OF THE COASTLINE OF THE LEEWARD BIG ISLAND. THIS HIGH SURF
EPISODE WILL LIKELY CONTINUE INTO WEDNESDAY.

AS A RESULT OF THIS LARGE SWELL...SMALL CRAFT ADVISORIES WILL BE
ISSUED FOR TONIGHT THROUGH WEDNESDAY AFTERNOON FOR ALL COASTAL
WATERS AND CHANNELS...EXCLUDING MAALAEA BAY AND THE PAILOLO CHANNEL.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY THROUGH TONIGHT FOR HALEAKALA SUMMIT AND THE SUMMITS
OF THE BIG ISLAND.

SMALL CRAFT ADVISORY TONIGHT THROUGH WEDNESDAY AFTERNOON FOR ALL
COASTAL WATERS AND CHANNELS...EXCLUDING MAALAEA BAY AND THE PAILOLO
CHANNEL.

&&

HOUSTON