Hawaii, 2004

Heavy Rain in Hawaii, August 4, 2004

August 4, 2004 · NWS HFO · 1 event in 1 county or zone

An upper trough enhancing remnants from Hurricane Darby generated heavy showers and isolated thunderstorms over the eastern half of Kauai. This caused small stream and drainage ditch flooding, and ponding of roadways.

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

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The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS HFO wrote it up.

An upper trough enhancing remnants from Hurricane Darby generated heavy showers and isolated thunderstorms over the eastern half of Kauai. This caused small stream and drainage ditch flooding, and ponding of roadways. No serious property damage or injuries were reported, however.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Honolulu, HI wrote its last area forecast discussion before the first event at Aug 3, 8:30 PM HST, 4 hours 55 minutes earlier.

Area forecast discussion, Aug 3, 8:30 PM HST, 4 hours 55 minutes before
HAWAIIAN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST TUE AUG 3 2004

.SYNOPSIS...
THE REMNANT TROPICAL MOISTURE FROM TROPICAL STORM DARBY WILL
CONTINUE TO BRING SHOWERS...SOME HEAVY...TO THE ISLANDS TONIGHT AND
INTO WEDNESDAY. TRADE WINDS...WITH THEIR MORE NORMAL PATTERN OF
WINDWARD AND MAUKA...NIGHT AND MORNING SHOWERS...WILL RETURN ON
THURSDAY.

&&

.DISCUSSION...
HEAVY SHOWERS WHICH HAVE BEEN AFFECTING MOSTLY THE BIG ISLAND AND
MAUI LAST NIGHT AND TODAY...ARE MOVING WEST. A SURFACE TROUGH...THE
REMNANT OF EX-TROPICAL STORM DARBY...IS NOW ORIENTED SOUTHWEST
THROUGH NORTHEAST AND LIES THROUGH THE KAIWI CHANNEL BETWEEN OAHU
AND MOLOKAI. A PLUME OF MOIST TROPICAL AIR IS BEING PULLED
NORTHWARD ALONG THE EAST SIDE OF THIS TROUGH...WITH DRIER NORTH TO
NORTHEASTERLY FLOW ALONG THE WEST SIDE OF THE TROUGH. SHOWERS...SOME
BRIEFLY HEAVY...MARK THE TROUGH AND EXTEND EAST TO BEYOND THE BIG
ISLAND. THE TROUGH AND SHOWERS ARE MOVING WESTWARD AT ABOUT 10 MPH
AND WILL AFFECT ALL ISLANDS THROUGH THE NIGHT TONIGHT AND INTO
WEDNESDAY. IT APPEARS MOISTURE MOVING UP FROM THE SOUTH WILL
CONVERGE WITH MOISTURE MOVING WESTWARD NORTH OF THE ISLANDS RIGHT
OVER OAHU LATER TONIGHT.

BY THURSDAY AND FRIDAY MORE TYPICAL TRADE WIND WEATHER IS EXPECTED
THANKS TO HIGH PRESSURE FAR NORTH OF THE STATE. TRADE WINDS WILL BE
IN THE 10 TO 20 MPH RANGE WITH SHOWERS MAINLY CONFINED TO WINDWARD
AND MAUKA AREAS.

&&

.LONG TERM...
WE ARE ALSO WATCHING ANOTHER AREA OF SHOWERY WEATHER THAT MAY
APPROACH THE ISLANDS OVER THE WEEKEND. TROPICAL DEPRESSION SIX-E IS
LOCATED ABOUT 1500 MILES EAST SOUTHEAST OF HONOLULU. THE NATIONAL
HURRICANE CENTER IN MIAMI HAS ISSUED ITS LAST ADVISORY ON THIS SYSTEM
BUT THE GFS AND NOGAPS MODELS STILL BRING A LARGE AREA OF REMNANT
TROPICAL MOISTURE OVER THE STATE LATE FRIDAY INTO SATURDAY BRINGING
THE THREAT OF HEAVY RAINFALL ONCE AGAIN TO THE STATE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH ALL ISLANDS.
HIGH SURF ADVISORY EAST SHORES OF KAUAI OAHU MOLOKAI MAUI AND THE
BIG ISLAND.

&&

FARRELL

In the hours before

Local storm report, Aug 3, 8:08 PM HST, 5 hours 17 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HONOLULU HI
808 PM HST TUE AUG 03 2004

..TIME...   ...EVENT...     ...CITY LOCATION...      ...LAT.LON...
..DATE...   ....MAG....     ..COUNTY LOCATION...ST.. ...SOURCE....
            ..REMARKS..

0435 AM     FLASH FLOOD      KAILUA-KONA             19.64N 155.99W
08/03/2004                   HAWAII             HI   EMERGENCY MNGR

            EXCESSIVE RUNOFF REPORTED IN DOWNTOWN STREETS OF TOWN.

&&

FARRELL

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 heavy rain. Local standard time, as filed.

Heavy Rain, Kauai

When
August 4, 1:25 AM HST to 4:15 AM HST
Where
Kauai County, Hanalei
Reported by
OFFICIAL NWS OBS.
Coordinates
22.011, -159.705 (the zone’s center; the record gives no point)

What these are

Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Hawaii in 2004Every state in 2004This day in weather historyWarnings in Hawaii, August 2004

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5431601.