Heavy Rain in Hawaii, June 8, 2003

HAWAIIAN ISLANDS SYNOPTIC DISCUSSION AND GUIDANCE
NATIONAL WEATHER SERVICE HONOLULU HI
10 AM HST SUN JUN 8 2003

SUMMARY...EXPECT A NEAR REPEAT OF YESTERDAYS WEATHER...WITH HEAVY
AFTERNOON SHOWERS OVER INTERIOR SECTIONS ONCE AGAIN TODAY. TRADE
WINDS WILL BEGIN THEIR RETURN ON MONDAY...STRENGTHENING TUESDAY...
AND CONTINUING THROUGH THE COMING WEEK. NIGHT AND MORNING TRADE
SHOWERS WILL ACCOMPANY THE RETURN OF THE TRADES.

SATELLITE...THE RATHER DEEP UPPER LEVEL TROUGH THAT HELPED PRODUCE
THE UNSTABLE ATMOSPHERIC CONDITIONS ACROSS HAWAII YESTERDAY HAS
PASSED TO THE NORTHEAST OF HAWAII. HOWEVER...WATER VAPOR IMAGERY
INDICATED THAT A MIDDLE TO UPPER LEVEL SHORT WAVE WAS IN THE
VICINITY OF THE ISLANDS. THERE WAS STILL EVIDENCE OF LOW-LEVEL
CONVERGENCE IN THE VICINITY OF THE WESTERN ISLAND CHAIN AGAIN THIS
MORNING. NEAR THE BIG ISLAND AND MAUI...THE LOW CLOUD MOTIONS WERE
GENERALLY TOWARD THE WEST SOUTHWEST AT 5 TO 10 MPH. THE LOW CLOUDS
NEAR KAUAI AND OAHU WERE PRIMARILY MOVING EASTWARD AT ABOUT 5 MPH.
FINALLY...THE LOW CLOUDS JUST NORTH OF OAHU WERE DRIFTING SLOWLY
TOWARD THE NORTH NORTHWEST. THERE WAS A RATHER PERSISTENT LINE OF
TOWERING CUMULUS CLOUDS IN THE KAUAI CHANNEL THAT APPEARED TO BE
RELATED TO THIS LOW-LEVEL CONVERGENT FLOW. THIS SHORT WAVE ALOFT AND
THE LOW-LEVEL CONVERGENCE MAY AGAIN SUPPORT AN UNSTABLE ATMOSPHERE
OVER THE ISLANDS...ESPECIALLY WHEN LOCAL SEABREEZE CIRCULATIONS
BECOME ESTABLISHED LATER THIS MORNING AND DURING THE AFTERNOON.

DISCUSSION...THE LIHUE SOUNDING REFLECTS AN EVEN MORE UNSTABLE DAY
TODAY...SO A REPEAT PERFORMANCE OF HEAVY SHOWERS BY AFTERNOON CAN BE
EXPECTED TODAY...MAINLY ON KAUAI AND OAHU...BUT ALSO POSSIBLY OVER
MUCH OF MAUI COUNTY...AND PERHAPS THE BIG ISLAND AS WELL. LIGHT
WINDS ARE PREVALENT OVER ALL ISLANDS THIS MORNING...AND THIS WILL
ALLOW SEA BREEZES ONCE AGAIN TO DEVELOP AND CONVERGE OVER THE
CENTRAL PORTIONS OF ALL ISLANDS...WITH SUBSEQUENT CONVECTION AND
HEAVY SHOWERS DEVELOPMENT DURING THE AFTERNOON HOURS...WITH CLEARING
BY EVENING.

FORECAST MODELS ARE STILL BUILDING THE HIGH PRESSURE FAR OFF TO OUR
NORTHEAST...NEAR THE PACIFIC NORTHWEST...SOUTHWESTWARD...TO
REINFORCE THE SUBTROPICAL HIGH NORTH OF THE STATE AND BRING A RETURN
OF OUR TRADE WINDS BY MONDAY. THESE WILL STRENGTHEN TUESDAY AND
REMAIN IN PLACE THROUGH THE COMING WEEK. THE RETURN OF TRADE WINDS
WILL ALTER HAWAII WEATHER SIGNIFICANTLY FROM THE AFTERNOON CLOUD AND
SHOWER PATTERN SEEN OVER THE PAST WEEK OR MORE. CLOUD COVER AND
SHOWERS WILL ONCE AGAIN FAVOR WINDWARD AND MAUKA AREAS...MOSTLY AT
NIGHT AND DURING THE MORNING HOURS.

SOUTH SWELL IS EXPECTED TO CONTINUE THE HIGH SURF ALONG SOUTH SHORES
STATEWIDE TODAY. SURF WILL DECREASE THROUGH THE COMING WEEK.

FARRELL

.HFO...HIGH SURF ADVISORY FOR SOUTH SHORES
.      SMALL CRAFT ADVISORY FOR SOUTH SWELL