High Surf in Hawaii, May 17 to 20, 2001

AFDHI
HAWAIIAN ISLANDS SYNOPTIC DISCUSSION AND GUIDANCE
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST THU MAY 17 2001

SUMMARY...THE TRADES ARE GETTING A LITTLE LIGHTER AND TURNING MORE
EAST SOUTHEASTERLY OVER THE NORTHERN ISLANDS AS A TROUGH DEVELOPS TO
THE WEST OF THE STATE. RAINFALL WILL BE SPOTTY BUT COULD BE BRIEFLY
HEAVY.

DISCUSSION...THE UPPER LOW THAT HAS BEEN MEANDERING AROUND TO THE
EAST OF THE ISLANDS IS PRESENTLY DRIFTING NORTHWARD. ITS INFLUENCE
ON ISLANDS WEATHER REMAINS MINOR AND IS MAINLY RESTRICTED TO
INCREASED INSTABILITY OVER OUR AREA. OUR PRESSURES ARE STILL
DROPPING AT A RATE OF CLOSE TO 2 MILLIBARS IN 24 HOURS. AS POINTED
OUT IN THE PREVIOUS DISCUSSION THESE PRESSURE FALLS ARE OCCURING ON
A LARGER SCALE ENCOMPASSING THE AREA BETWEEN HERE AND MIDWAY ISLAND
AND BEYOND. HIGH LATITUDE BLOCKING CENTERED OVER THE WESTERN
ALEUTIANS AND KAMCHATKA IS INDUCING TROUGHINESS TO THE SOUTH OF THE
HIGH STRETCHING FROM JAPAN EASTWARD TO MIDWAY AND ON TOWARD HAWAII.
THIS APPEARS TO BE A TRANSIENT FEATURE AS THE PROGS SHOW THAT THE
HIGH TO THE NORTHWEST OVER THE ALEUTIANS WILL BUILD SOUTHEASTWARD
TOWARD HAWAII AND RETURN OUR PRESSURES TO THE NEAR NORMAL 1018 TO
1020 MB IN A COUPLE OF DAYS.  IN ANY EVENT IT LOOKS LIKE THE FLOW
WILL REMAIN RATHER SLUGGISH WITH WINDS REMAINING ON THE LIGHT SIDE.
THE RAINFALL PATTERN WILL THEREFORE BECOME A MIX OF BOTH
NIGHT AND MORNING TRADE SHOWERS AND SOME LOCALIZED AFTERNOON
CONVECTIVE ONES..CONVECTION WILL TEND TO FAVOR THE WEST OR NORTHWEST
SIDES OF MOST ISLANDS.

SURF...SOUTHERLY SURF WILL INCREASE TO 6 FEET THIS EVENING AND ON
FRIDAY. ADVISORY WAS ISSUED AT 6 PM.  RORSENDAL

.PHFO......WARNINGS.....NONE
.          WATCHES......NONE
.          ADVISORIES...HIGH SURF SOUTH SHORES