000 FZHW70 PHFO 130711 MWSHFO MARINE WEATHER STATEMENT NATIONAL WEATHER SERVICE HONOLULU HI 900 PM HST SUN DEC 12 2004 PHZ110>124-131900- KAUAI NORTHWEST WATERS-KAUAI WINDWARD WATERS- KAUAI LEEWARD WATERS-KAUAI CHANNEL-OAHU WINDWARD WATERS- OAHU LEEWARD WATERS-KAIWI CHANNEL-MAUI COUNTY WINDWARD WATERS- MAUI COUNTY LEEWARD WATERS-MAALAEA BAY-PAILOLO CHANNEL- ALENUIHAHA CHANNEL-BIG ISLAND WINDWARD WATERS- BIG ISLAND LEEWARD WATERS-BIG ISLAND SOUTHEAST WATERS- 900 PM HST SUN DEC 12 2004 ...LARGE NORTHWEST SWELLS WILL IMPACT HAWAIIAN COASTAL WATERS THIS WEEK... A SERIES OF POWERFUL STORMS IN THE NORTHWEST PACIFIC...THE SAME STORMS FORCING THE SUBTROPICAL RIDGE OVER THE ISLANDS...WILL SEND LARGE NORTHWEST SWELLS TO THE ISLANDS THIS WEEK. THE FIRST SWELL WILL ARRIVE OVERNIGHT AND PRODUCE SURF VERY CLOSE TO THE NORTH SHORE WARNING LEVEL OF 25 FEET. FORERUNNERS FROM THIS SWELL REACHED BUOY 51001 AROUND MIDDAY SUNDAY AND HAVE BEEN SLOWLY INCREASING IN ENERGY. A HIGH SURF ADVISORY IS IN EFFECT FOR NORTH AND WEST FACING SHORES OF ALL ISLANDS...EXCEPT FOR THE WEST FACING SHORES OF THE BIG ISLAND WHICH WILL BE SHADOWED. WHILE SURF FROM THIS SYSTEM MAY BRIEFLY DIP BELOW ADVISORY LEVELS TUESDAY AFTERNOON...A VERY LARGE NORTHWEST SWELL WILL START TO ARRIVE TUESDAY EVENING. THE TWO STORMS GENERATING THIS SECOND SWELL DEVELOPED ACROSS THE NORTHWEST AND CENTRAL NORTH PACIFIC AS FORECAST. THE INTERACTION OF THESE TWO STORMS PRODUCED AN UNUSUALLY LONG FETCH OF NORTHWEST WINDS AIMED TOWARDS THE MAIN HAWAIIAN ISLANDS. SHIP OBSERVATIONS IN THE AREA INDICATE AT LEAST 40 KNOT SUSTAINED WINDS THROUGHOUT THE ENTIRE FETCH. SURF WILL BUILD RAPIDLY TUESDAY NIGHT...REACHING HEIGHTS WELL ABOVE THE WARNING THRESHOLD OF 25 FEET BY SUNRISE WEDNESDAY ALONG THE EXPOSED NORTH FACING SHORES OF ISLANDS. WARNINGS WILL ALSO BE NEEDED FOR WEST FACING SHORES OF KAUAI...OAHU...AND MOLOKAI. SWELL SHADOWING DUE TO THE ISLANDS OF MAUI COUNTY WILL CREATE A TRICKY FORECAST FOR THE KONA COAST OF THE BIG ISLAND. WHILE ADVISORY LEVEL SURF...8 FEET FOR THE KONA COAST...IS EXPECTED AT A MINIMUM...WHETHER IT WILL REACH THE WARNING LEVEL OF 12 FEET IS NOT AS CLEAR CUT. WE ARE WATCHING THIS SWELL VERY CLOSELY SINCE THE SURF WILL LIKELY BE LARGE ENOUGH TO WASH OVER COASTAL ROADS AND DAMAGE PROPERTY ALONG PORTIONS OF THE AFFECTED SHORELINES. IN ADDITION TO THE LARGE SURF...AN EXTREME HIGH TIDE IS EXPECTED AROUND SUNRISE WEDNESDAY MORNING. THE SURF WILL SLOWLY SUBSIDE BELOW WARNING LEVELS BY THURSDAY...BUT REMAIN ABOVE ADVISORY LEVELS INTO SATURDAY. ACROSS HAWAIIAN COASTAL WATERS...OPEN OCEAN SWELLS WILL BUILD SUNDAY NIGHT...REACHING 12 TO 13 FEET MONDAY. SWELL HEIGHTS WILL BRIEFLY SUBSIDE TO AROUND 10 FEET TUESDAY...BUT RAPIDLY BUILD TUESDAY EVENING...REACHING 20 FEET AND POSSIBLY HIGHER BY MIDNIGHT AND REMAIN AT THIS LEVEL WEDNESDAY. THE SWELL WILL GRADUALLY SUBSIDE THURSDAY...BUT REMAIN ELEVATED AT 10 TO 13 FEET THURSDAY NIGHT. OPEN OCEAN SWELL HEIGHTS MAY POSSIBLE RISE TO 15 FEET FRIDAY. HARBORS EXPOSED TO NORTHWEST AND NORTH FACING SWELLS MAY SEE HARBOR SURGES THAT WILL BE DAMAGING TO MOORED VESSELS. IN ADDITION...WAVES BREAKING ACROSS HARBOR ENTRANCES WILL CREATE ADDITIONAL HAZARDS...ESPECIALLY FOR THE TUESDAY NIGHT AND WEDNESDAY EVENT. STAY TUNED TO NOAA WEATHER RADIO AND LOCAL MEDIA SOURCES FOR UPDATES. $$ TANABE