High Surf in Hawaii, March 25 to 28, 2009

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
326 AM HST WED MAR 25 2009

.SYNOPSIS...
HIGH PRESSURE FAR NORTHEAST OF THE ISLANDS WILL PROVIDE MODERATE
TO FRESH TRADE WINDS THROUGH THE WEEK. THE TRADE WINDS WILL REMAIN
OUT OF THE EAST SOUTHEAST OVER THE SMALLER ISLANDS FOR THE NEXT
COUPLE OF DAYS...THEN BECOME EASTERLY BY THE END OF THE WEEK.
PASSING SHOWERS WILL FOCUS OVER WINDWARD AND MAUKA AREAS.

&&

.DISCUSSION...
THE ATMOSPHERE HAS BECOME MORE STABLE OVER THE PAST 24 HOURS AND
COMPARED TO MONDAY NIGHT...RAINFALL HAS BEEN MINIMAL WITH ONLY
SELECT LOCATIONS SEEING ANY SIGNIFICANT RAINFALL. THE WINDWARD BIG
ISLAND HAD THE MOST COVERAGE WITH UPWARDS OF A QUARTER OF AN INCH
FALLING FROM LAUPAHOEHOE TO GLENWOOD. EVEN THE RAINFALL JUGGERNAUT
MOUNT WAIALEALE HAS DROPPED IN RAINFALL PRODUCTION...ONLY TAKING IN
0.11 INCHES OVER A 6 HOUR PERIOD...COMPARED TO 0.56 INCHES FOR THE
6 HOURS ENDING AT 8PM LAST NIGHT.

A 1039 MB SURFACE HIGH LOCATED FAR NORTHEAST OF THE ISLANDS NEAR
37N141W IS BRINGING MODERATE TO FRESH TRADE WINDS TO THE ALOHA
STATE. AN INTENSIFYING SURFACE TROUGH WEST OF KAUAI CONTINUES TO
TURN THE TRADE WINDS OUT OF THE EAST SOUTHEAST...INSTEAD OF THE
NORMAL NORTHEAST DIRECTION. THE TROUGH AND EMBEDDED SURFACE LOW IS
EXPECTED TO LINGER WEST OF THE ISLANDS NEAR 170W THROUGH THE
WEEK...KEEPING THE WINDS OVER THE SMALLER ISLANDS OUT OF EAST
SOUTHEAST.

THE SURFACE HIGH IS EXPECTED TO REMAIN IN PLACE THROUGH THE
WEEK...KEEPING IT/S PRESENT INTENSITY THROUGH THURSDAY AND THEN
SLOWLY WEAKEN INTO THE WEEKEND. WINDS CAN BE EXPECTED TO REMAIN AT
MODERATE TO FRESH LEVELS THROUGH THE FORECAST PERIOD AS THE
PRESSURE GRADIENT OVER THE ISLANDS REMAINS IN PLACE. SATELLITE
MOISTURE ESTIMATES AND THE GFS SHOW LIMITED VALUES UPSTREAM OF THE
ISLANDS OUT TO 150W AND STEADILY INCREASING VALUES FARTHER EAST.
SHOWER ACTIVITY WILL REMAIN SPARSE TODAY...AND FOCUSED OVER
WINDWARD AND MAUKA LOCATIONS. THE GFS TRACKS THE INCREASED
MOISTURE EAST OF 150W INTO THE BIG ISLAND FRIDAY...LIKELY BRINGING
AN UP TICK IN TRADE WIND SHOWERS FOR THE WINDWARD BIG ISLAND.

THE GFS SHOWS A LARGER MOISTURE POOL REACHING THE ISLANDS BY
SUNDAY AND REMAINING INTO THE BEGINNING OF NEXT WEEK. IN THE UPPER
LEVELS...THE GFS ALSO SHOWS A TROUGH FORMING OVER THE ISLANDS.
THE COMBINATION OF INCREASED MOISTURE AND UPPER LEVEL INSTABILITY
WILL LIKELY LEAD TO WETTER TRADE WIND SHOWERS SUNDAY AND INTO NEXT
WEEK.

&&

.MARINE...
THE HIGH SURF ADVISORY FOR EAST FACING SHORES CONTINUES. LONGER
PERIOD SWELL IS EXPECTED TO REACH THE ISLANDS THURSDAY BRINGING A
SLIGHT INCREASE TO SURF HEIGHTS. THE SURF WILL ALSO REMAIN ROUGH
AND SLOPPY WITH CONTINUED TRADES. THIS ADVISORY MAY REQUIRE AN
EXTENSION BEYOND 6 AM HST FRI.

A HURRICANE FORCE LOW NEAR THE DATELINE PRODUCED A WNW SWELL CURRENTLY
SLATED TO ARRIVE WEDNESDAY AND BUILD TO NEAR ADVISORY LEVELS ON
WEDNESDAY NIGHT AND THURSDAY. GIVEN THE WESTERLY COMPONENT OF THE
SWELL...290-300 DEG...A SIGNIFICANT AMOUNT OF SWELL WILL CLIP
EXPOSED W FACING SHORES OF THE BIG ISLAND ON THU.

THE SCA REMAINS FOR COASTAL ZONES EXPOSED TO THE STEEP EAST WIND SWELL
AND FRESH TRADE WINDS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 AM HST FRIDAY FOR KAUAI WINDWARD-OAHU
KOOLAU-OLOMANA-MOLOKAI WINDWARD-MAUI WINDWARD WEST-WINDWARD
HALEAKALA-SOUTH BIG ISLAND-BIG ISLAND NORTH AND EAST.

SMALL CRAFT ADVISORY UNTIL 6 AM HST FRIDAY FOR KAUAI NORTHWEST
WATERS-KAUAI WINDWARD WATERS-KAUAI CHANNEL-OAHU WINDWARD WATERS-
KAIWI CHANNEL-MAUI COUNTY WINDWARD WATERS-MAALAEA BAY-PAILOLO
CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG ISLAND
SOUTHEAST WATERS.

&&

MORRISON