High Surf in Hawaii, March 19 to 20, 2011

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
850 PM HST SAT MAR 19 2011

.SYNOPSIS...
GUSTY TRADE WINDS WILL FOCUS SCATTERED TO NUMEROUS SHOWERS ALONG
WINDWARD TERRAIN THROUGH TONIGHT. THE TRADES WILL DECREASE SLIGHTLY
THROUGH MONDAY AS THE AIRMASS DRYS OUT. TRADE WINDS WILL BECOME
STRONG AND WINDWARD SHOWERS WILL INCREASE AGAIN NEXT WEEK AS HIGH
PRESSURE REBUILDS OVER THE CENTRAL NORTH PACIFIC.
&&

.DISCUSSION...
GUSTY TRADE WINDS CONTINUE TO BLOW ACROSS THE ISLANDS DUE TO A HIGH
PRESSURE SYSTEM NORTH OF THE ISLANDS. CLOUDS AND SHOWERS ARE RIDING
IN ON THE TRADES...BRINGING BOTH TO MOSTLY THE WINDWARD AND MAUKA
AREAS OF THE ISLANDS.

TRADES ARE EXPECTED TO CONTINUE FOR THE FORESEEABLE FUTURE AS THE
HIGH NORTH OF THE ISLANDS WILL BE REPLACED BY ANOTHER HIGH OVER THE
WEEKEND. AS THE NEW HIGH BUILDS IN...WE WILL SEE A SMALL DROP IN
TRADE WIND SPEEDS THROUGH MONDAY.

A SLIGHTLY DRIER AIRMASS IS MOVING TOWARDS THE ISLANDS TONIGHT ON
THE TRADE WIND FLOW...WHICH SHOULD RESULT IN FEW SHOWERS ON SUNDAY
AND INTO THE BEGINNING OF THE NEW WORK WEEK. A COLD FRONT MOVING TO
THE EAST NORTH OF THE HIGH WILL INTRODUCE ADDITIONAL MOISTURE INTO
THE TRADE WIND FLOW FOR THE MIDDLE PART OF THE WEEK.

WINDS HAVE REMAINED GUSTY OVER MAUI AND THE BIG ISLAND...WHERE THE
WIND ADVISORY REMAINS POSTED. WILL BE MONITORING CLOSELY
TONIGHT...BUT DO ANTICIPATE THE WINDS TO DROP BELOW ADVISORY LEVELS
BY SUNRISE.

NO CHANGES TO THE GRIDS AT THIS TIME.

&&

.MARINE...
THE ELEVATED TRADES AND SWELL WILL LIKELY KEEP THE SMALL CRAFT
ADVISORY AROUND. CURRENTLY IT IS SET TO EXPIRE SUNDAY
AFTERNOON...BUT IT WILL LIKELY BE EXTENDED DUE TO A COMBINATION OF
WINDS AND SEAS.

NO CHANGES TO THE SURF...WITH THE ADVISORY FOR EAST FACING SHORES
CONTINUING THROUGH SUNDAY AFTERNOON. THE NORTHWEST SWELL WILL IMPACT
THE NORTH SHORES OF KAUAI AND OAHU...WITH THE REMAINING ISLANDS
BEING SOMEWHAT SHADOWED. THESE ISLANDS WILL SEE AN INCREASE IN SURF
ALONG NORTH FACING SHORES...BUT IT IS EXPECTED TO REMAIN BELOW THE
15 FT ADVISORY LEVELS THERE. THIS SWELL WILL DROP OFF SLOWLY INTO
NEXT WEEK WITH ANOTHER ROUND OF SMALLER NORTHWEST SWELL DUE THURSDAY.

&&

.AVIATION...
THE STRONG HIGH PRESSURE NORTH OF HAWAII WILL CONTINUE TO DRIVE
STRONG TRADE WINDS ACROSS THE AREA...AND AS SUCH...AIRMET TANGO
REMAINS IN EFFECT FOR MECHANICALLY GENERATED MODERATE TURBULENCE ON
LEEWARD SIDES OF THE ISLANDS BELOW 9000 FEET. THE SHOWERS IMPACTING
THE MOSTLY WINDWARD AND MAUKA AREAS MAY RESULT IN SOME OCCASIONAL
MVFR CIGS AND MOUNTAIN OBSCURATIONS...BUT AREAL COVERAGE IS NOT BE
WIDESPREAD ENOUGH TO WARRANT AN AIRMET FOR IT. A JET STREAK
WILL DEVELOP ON THE SOUTHERN FLANK OF THE NEARBY UPPER LOW TONIGHT
WHICH COULD PRODUCE SOME UPPER LEVEL TURBULENCE OVER AND SOUTH OF
THE HAWAII.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 AM HST MONDAY FOR NIIHAU-KAUAI
WINDWARD-KAUAI LEEWARD-OAHU NORTH SHORE-OAHU KOOLAU.

HIGH SURF ADVISORY UNTIL 6 PM HST SUNDAY FOR OLOMANA-MOLOKAI
WINDWARD-MAUI WINDWARD WEST-WINDWARD HALEAKALA-SOUTH BIG ISLAND-
BIG ISLAND NORTH AND EAST.

WIND ADVISORY UNTIL 6 AM HST SUNDAY FOR KAHOOLAWE-MAUI-KONA-
SOUTH BIG ISLAND-BIG ISLAND NORTH AND EAST-KOHALA-BIG ISLAND
INTERIOR.

SMALL CRAFT ADVISORY UNTIL 6 PM HST SUNDAY FOR ALL HAWAIIAN
WATERS-

&&