High Surf in Hawaii, April 16 to 18, 2004

HAWAIIAN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
10 AM HST FRI APR 16 2004

.SYNOPSIS...
BRISK TRADE WINDS WILL BRING PASSING SHOWERS TO THE ISLANDS
TODAY. SUNNIER AND DRIER CONDITIONS ARE EXPECTED OVER THE WEEKEND
AND DURING THE EARLY PART OF NEXT WEEK. LESS WINDY CONDITIONS ARE
EXPECTED FROM SUNDAY ON.

&&

.DISCUSSION...
A 1035 MB HIGH PRESSURE SYSTEM NORTHEAST OF THE ISLANDS IS CENTERED
NEAR 39N 150W. IT IS SLOWLY MOVING SOUTH TO MAINTAIN A STRONG
PRESSURE GRADIENT FOR BRISK TRADE WINDS OVER THE STATE. THE HIGH IS
FORECASTED TO BE CENTERED NEAR 31N 150W AT 1031 MB IN 24 HOURS...
AND NEAR 29N 155W AT 1027MB IN 48 HOURS. A HIGH OF THIS STRENGTH AND
MOVING ALONG THIS TRAJECTORY WILL CAUSE STRONG AND GUSTY TRADES
OVER THE STATE...THOUGH BY SUNDAY WITH THE CENTER THEN SOUTH OF 30N
SOME RELAXATION OF THE PRESSURE GRADIENT AND WINDS WILL LIKELY
OCCUR. THE INCREASING ANTICYCLONIC VORTICITY IN THE FORM OF BOTH
CURVATURE AND SHEAR OF THE BOUNDARY LAYER FLOW AS THE CENTER OF THE
HIGH APPROACHES SHOULD ALSO MEAN SUNNIER AND DRIER WEATHER.  THE
MODELS HOWEVER DO BRING A WEAK TROUGH IN THE UPPER WESTERLIES TOWARD
THE ISLANDS FROM THE WEST ALREADY BEGINNING LATE MONDAY FOR THE
CHANCE OF SOME SHOWERS THROUGH MIDWEEK. MODERATE TRADE WINDS WILL
PERSIST IN THE LOWER LAYERS.

SURF...THE STRONG TRADES TO THE EAST OF THE STATE AND OVER THE STATE
HAVE MADE FOR ROUGH SURF ALONG THE EAST FACING SHORES. A HIGH SURF
ADVISORY HAS THEREFORE BEEN ISSUED AT 10 AM FOR 6 TO 10 FOOT SURF
ALONG THESE SHORELINES. THIS HIGH SURF ADVISORY WILL LIKELY BE UP AT
LEAST THROUGH SATURDAY.

&&

.WATCHES/WARNINGS/ADVISORIES...
 SMALL CRAFT ADVISORY...ALL WATERS.
 HIGH SURF ADVISORY AT 10 AM FOR EAST SHORES.

ROSENDAL