High Surf in Hawaii, March 1 to 5, 2009

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST SAT FEB 28 2009

.SYNOPSIS...
HIGH PRESSURE TO THE NORTH WILL MAINTAIN TRADE WINDS OVER THE
ISLANDS THROUGH NEXT WEEK. THE HIGH PRESSURE WILL REMAIN STRONG
ENOUGH TO KEEP THE TRADES LOCALLY WINDY THROUGH WEDNESDAY. TRADES
WILL FOCUS SHOWERS OVER WINDWARD AREAS...BUT THE ATMOSPHERE WILL
REMAIN DRY AND STABLE...SO RAINFALL WILL BE LIGHT. TOWARD THE END OF
THE WEEK THE HIGH...AND THE TRADES...WILL WEAKEN. THE ATMOSPHERE
WILL BECOME MORE MOIST LATE IN THE WEEK SO SHOWERS MAY BECOME MORE
ACTIVE.

&&

.DISCUSSION...
SURFACE OBSERVATIONS SHOW WIDESPREAD BREEZY TRADE WINDS. LOW CLOUDS
ARE GENERALLY BROKEN OVER WINDWARD AREAS AND SCATTERED OVER LEE
AREAS WITH THIN CIRRUS ABOVE. RADAR IMAGERY SHOWS ISOLATED TO
SCATTERED SHOWERS MOVING OVER THE ISLANDS IN THE TRADE-WIND FLOW.
THERE WILL BE LITTLE CHANGE OVERNIGHT.

A STRONG HIGH...WITH A CENTRAL PRESSURE NEAR 1040 MB...SITS FAR
NORTH NORTHWEST OF THE ISLANDS. THE PRESSURE GRADIENT SOUTH OF THE
HIGH IS TIGHT ENOUGH TO PRODUCE BREEZY TRADE WINDS OVER THE ISLANDS.
OVER THE NEXT FEW DAYS THE HIGH WILL MOVE SOUTHEAST AND WEAKEN. THE
PRESSURE GRADIENT OVER THE ISLANDS WILL REMAIN TIGHT AND THE TRADES
WILL REMAIN BREEZY. AS THE HIGH MOVES SOUTHEAST THE TRADE-WIND
DIRECTION WILL GRADUALLY SHIFT FROM NORTHEAST TO EAST NORTHEAST. THE
WIND ADVISORY MAY NEED TO BE EXTENDED BEYOND TOMORROW MORNING.

THE TRADE WINDS WILL CARRY SOME SHOWERS OVER THE ISLANDS BUT THE
ATMOSPHERE WILL REMAIN DRY AND STABLE FOR THE NEXT FEW DAYS...SO
RAINFALL WILL BE LIGHT. SHOWERS WILL BE MOST ACTIVE NIGHTS AND
MORNINGS. THE SHOWERS WILL BE FOCUSED MAINLY OVER WINDWARD
AREAS...BUT SINCE THE WINDS ARE SO STRONG...ISOLATED SHOWERS WILL
SPREAD LEEWARD ON THE SMALLER ISLANDS.

LOW TEMPERATURES HAVE BEEN NEAR NORMAL BUT HIGH TEMPERATURES HAVE
BEEN COOLER THAN NORMAL. THE STRONG WINDS AND LOW HUMIDITIES ARE
MAKING IT FEEL MORE CHILLY THAN THE TEMPERATURES WOULD SUGGEST.
THESE CONDITIONS WILL CONTINUE THROUGH AT LEAST EARLY NEXT WEEK.

BY WEDNESDAY NIGHT...THE PRESSURE GRADIENT WILL WEAKEN A BIT AND OUR
TRADE WINDS WILL TAPER OFF. THE COMPUTER MODELS ALSO SUGGEST THAT
ATMOSPHERIC MOISTURE WILL INCREASE...SO RAINFALL TOTALS MAY
INCREASE ABOVE THE RECENT VERY LOW AMOUNTS.

&&

.MARINE...
A GALE WARNING CONTINUES FOR THE ALENUIHAHA AND PAILOLO CHANNELS
WHILE A SMALL CRAFT ADVISORY CONTINUES FOR THE REST OF THE COASTAL
WATERS. ALSO...A HIGH SURF ADVISORY CONTINUES FOR EAST FACING SHORES
OF ALL THE ISLANDS. THE THREAT FOR MODERATE HARBOR SURGES AT KAHULUI
AND HILO HARBORS WILL ALSO CONTINUE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 AM HST SUNDAY FOR ALL AREAS EXCEPT THE BIG
ISLAND SUMMITS.

HIGH SURF ADVISORY UNTIL 6 AM HST MONDAY FOR EAST FACING SHORES OF
ALL ISLANDS.

GALE WARNING UNTIL 6 AM HST SUNDAY FOR THE PAILOLO AND ALENUIHAHA
CHANNELS.

SMALL CRAFT ADVISORY UNTIL 6 AM HST MONDAY FOR ALL REMAINING
HAWAIIAN COASTAL WATERS.

&&

DONALDSON