High Surf in Hawaii, March 18 to 19, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST SUN MAR 18 2007

.SYNOPSIS...MODERATE TO FRESH TRADE WINDS WILL CARRY SCATTERED
SHOWERS TO WINDWARD AND MAUKA SECTIONS OF THE ISLANDS THROUGH
TUESDAY. SOME SHOWERS MAY OCCASIONALLY DRIFT OVER TO LEEWARD
SECTIONS OF THE SMALLER ISLANDS. THE TRADE WIND SPEEDS WILL DECREASE
SLIGHTLY BY MID-WEEK.

&&

.DISCUSSION...A 1028 MB SURFACE HIGH NEAR 36N 164W CONTINUES TO
MAINTAIN MODERATE TO LOCALLY FRESH TRADES EARLY THIS MORNING. THIS
HIGH...WHICH IS MOVING NORTHEAST AT ABOUT 15 MPH...IS FORECAST TO BE
NEAR 38N 159W WITH A PRESSURE OF 1032 MB BY THIS EVENING.

LOW CLOUDS AND SHOWERS CONTINUE TO LINGER ACROSS PORTIONS OF THE
HAWAIIAN ISLANDS AND ADJACENT COASTAL WATERS EARLY THIS MORNING.
MOST OF THE CLOUDS AND SHOWERS ARE OVER WINDWARD SECTIONS OF THE
ISLANDS. HOWEVER...SOME OF THE PRECIPITATION HAS BEEN CARRIED OVER
TO THE LEEWARD SIDES OF SOME OF THE SMALLER ISLANDS BY THE BRISK
TRADE WINDS.

WATER VAPOR IMAGERY INDICATES STRONG SUBSIDENCE CONTINUES ALOFT OVER
THE HAWAIIAN ISLANDS. THIS SHOULD REMAIN THE CASE AS MIDDLE AND
UPPER TROPOSPHERIC RIDGING...WHICH IS EVIDENT IN THE SATELLITE
DERIVED UPPER LEVEL WIND VECTORS...CONTINUES TO BUILD OVER THE STATE
TODAY.

EXPECT CONTINUED STABILIZATION OF THE ATMOSPHERE ACROSS THE ALOHA
STATE. AS A RESULT...SOMEWHAT DRIER CONDITIONS WILL LIKELY DEVELOP
LATER TODAY AND TONIGHT. MOST SHOWERS THAT DO ARRIVE IN THE TRADES
WILL AFFECT THE WINDWARD AND MOUNTAIN AREAS OF THE ISLANDS.
HOWEVER...SINCE THE TRADES WILL BE RATHER BRISK...THERE IS A CHANCE
A FEW OF THE PRECIPITATION BEARING LOW CLOUDS WILL ARRIVE OVER ON
THE LEEWARD SIDES OF SOME OF THE SMALLER ISLANDS. THIS WILL BE
ESPECIALLY TRUE AT NIGHT AND EARLY IN THE MORNING.

A SURFACE TROUGH NORTH OF THE ISLANDS WILL CAUSE OUR TRADE WINDS TO
EASE SLIGHTLY BY WEDNESDAY. HOWEVER...THE TRADES ARE EXPECTED TO
REMAIN WITH US THROUGH THE END OF THIS WEEK.

&&

.MARINE...THE NORTHWEST SWELL ARRIVED AT BUOY 1 AROUND 400 PM HST
SATURDAY AFTERNOON. THE SWELL HEIGHT THERE WAS 11.5 FEET 17 SECONDS
FROM 310 DEGREES AT 300 AM HST THIS MORNING. IT SHOULD BE NOTED THAT
THE WAVE WATCH III MODEL OUTPUT INDICATED THE ESTIMATED SWELL HEIGHT
WOULD ONLY BE 9 FEET 16 SECONDS BY NOW AT BUOY 1. THE DATA FROM THE
WAIMEA BAY BUOY LOCATED JUST OFFSHORE OF NORTHERN OAHU INDICATES
THE SWELL ARRIVED AT OAHU A SEVERAL HOURS AGO. THE SURF PRODUCED BY
THIS SWELL WILL CONTINUE TO RISE RAPIDLY ALONG THE NORTH AND WEST
FACING SHORES OF MOST OF THE SMALLER HAWAIIAN ISLANDS THIS MORNING.
SURF WILL ALSO LIKELY REACH THE ADVISORY THRESHOLD ALONG PARTS OF
THE WEST FACING SHORES OF THE BIG ISLAND AFTER NOON HST TODAY.

MODERATE TO FRESH TRADE WINDS REQUIRED THE ISSUANCE OF A SMALL CRAFT
ADVISORY FOR THE TYPICALLY BREEZY MARINE ZONES LATE SATURDAY. IN
ADDITION...THE COMBINED SEAS ARE INCREASING TO 10 FEET OR GREATER
WITH THE ARRIVAL OF THE NEW NORTHWEST SWELL. THEREFORE...A SMALL
CRAFT ADVISORY HAS BEEN ISSUED FOR THOSE MARINE ZONES AROUND KAUAI
AND OVER MOST OF THE WINDWARD OAHU WATERS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY THROUGH 6 PM HST MONDAY FOR NORTH AND WEST
FACING SHORES OF NIIHAU KAUAI OAHU AND MOLOKAI AND NORTH FACING
SHORES OF MAUI.

HIGH SURF ADVISORY FROM NOON HST TODAY TO 6 AM HST MONDAY FOR WEST
FACING SHORES OF THE BIG ISLAND.

SMALL CRAFT ADVISORY UNTIL 8 PM HST TUESDAY FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND SOUTHEAST WATERS.

SMALL CRAFT ADVISORY UNTIL 6 AM HST MONDAY FOR WATERS AROUND KAUAI
AND THE WINDWARD OAHU WATERS.

&&

HOUSTON