Heavy Rain, Hawaii
- When
- August 2, 7:29 PM HST to 10:30 PM HST
- Where
- Hawaii County, 38 mi SW of Hilo
- Reported by
- OFFICIAL NWS OBS.
- Coordinates
- 19.602, -155.523 (the zone’s center; the record gives no point)
Heavy Rain in Hawaii, August 2, 2004
Heavy showers and isolated thunderstorms, associated with remnants from Hurricane Darby being enhanced by an upper trough, caused ponding of roadways, and small stream and drainage ditch flooding in the Kau District on the Big Island of Hawaii. There were no reports of serious property damage or injuries.
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
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.
Heavy showers and isolated thunderstorms, associated with remnants from Hurricane Darby being enhanced by an upper trough, caused ponding of roadways, and small stream and drainage ditch flooding in the Kau District on the Big Island of Hawaii. There were no reports of serious property damage or injuries.
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 2, 4:00 PM HST, 3 hours 29 minutes earlier.
Area forecast discussion, Aug 2, 4:00 PM HST, 3 hours 29 minutes before
HAWAIIAN ISLANDS FORECAST DISCUSSION NATIONAL WEATHER SERVICE HONOLULU HI 400 PM HST MON AUG 2 2004 .SYNOPSIS... LIGHT TO MODERATE TRADE WINDS WILL CONTINUE ACROSS THE ISLANDS THANKS TO AN AREA OF HIGH PRESSURE TO OUR NORTH. REMNANT MOISTURE FROM FORMER TROPICAL DEPRESSION DARBY WILL MOVE ACROSS THE ISLANDS TONIGHT THROUGH TUESDAY. THIS WILL CAUSE AN INCREASE IN SHOWERS OVER WINDWARD AND MAUKA AREAS WITH LEE AREAS GETTING SOME SHOWERS AT TIMES. ISOLATED THUNDERSTORMS ARE ALSO A POSSIBILITY THROUGH TOMORROW AS WELL. SHOWERS MAY INCREASE AGAIN BY THE END OF THE WEEK AS ANOTHER AREA OF MOISTURE IS EXPECTED TO MOVE THROUGH THE ISLANDS. && .DISCUSSION... AN AREA OF HIGH PRESSURE FAR TO THE NORTH OF THE ISLANDS WILL KEEP LIGHT TO MODERATE TRADE WINDS BLOWING ACROSS THE STATE THROUGH THE FORECAST PERIOD. OUR WINDS WILL DROP OFF A NOTCH TONIGHT THROUGH TUESDAY AS A WEAK TROUGH IN THE LOW LEVEL EASTERLIES MOVES THROUGH THE ISLANDS. THIS TROUGH WAS AT ONE TIME HURRICANE DARBY. LAST NIGHTS QUIKSCAT IMAGE SHOWED LIGHTER WINDS WITH THE SYSTEM BUT THIS MORNINGS PASS MISSED THE SYSTEM COMPLETELY. WETTER WEATHER IS EXPECTED OVER THE NEXT 24 TO 36 HOURS AS THE MOISTURE ASSOCIATED WITH THE REMNANTS OF DARBY PASS THROUGH THE ISLANDS FROM THE EAST. SHOWERS WILL FAVOR WINDWARD AND MAUKA AREAS BUT LEE AREA MAY ALSO GET IN ON SOME OF THE SHOWER ACTIVITY AS WELL. WE HAVE RAISED THE POPS FOR THE TONIGHT THROUGH TOMORROW PERIODS AND HAVE ALSO ADDED THUNDERSTORMS TO THE FORECAST THROUGH TOMORROW. ON WEDNESDAY AND THURSDAY OUR WEATHER WILL LIKELY RETURN TO A NORMAL TRADE WIND PATTERN WITH JUST THE USUAL SHOWER ACTIVITY EXPECTED MAINLY OVER WINDWARD AND MAUKA AREAS. ANOTHER AREA OF MOISTURE IS FORECAST TO MOVE INTO THE AREA BEGINNING AROUND FRIDAY AND WILL LIKELY AFFECT OUR WEATHER THRU SATURDAY. THIS AREA OF MOISTURE IS ASSOCIATED WITH WHAT IS NOW TROPICAL DEPRESSION SIX E. THIS MOISTURE AREA MAY PASS FURTHER SOUTH THAN DARBYS MOISTURE BUT WILL STILL UP THE POPS TO ACCOUNT FOR THE POTENTIAL OF INCREASED RAINFALL. IN THE UPPER LEVELS OF THE ATMOSPHERE A TROUGH OF LOW PRESSURE IS EXPECTED TO REMAIN JUST TO OUR NORTHWEST KEEPING CONDITIONS SLIGHTLY UNSTABLE THROUGH THE FORECAST PERIOD. THIS INSTABILITY IS EVIDENT ON BOTH THE LIHUE AND HILO SOUNDINGS. && .HFO WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH ALL ISLANDS. && BURKE
The radar
The national radar mosaic for the moment the first event began.
Event by event
1 heavy rain. Local standard time, as filed.
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
- High Wind in Washington, August 2, 2004
- Tornadoes and Hail in Minnesota, August 2, 2004
- Hail and Damaging Winds in South Dakota, August 2 to 3, 2004
- Flash Flooding and Hail in Michigan, August 2, 2004
- Hail and Damaging Winds in Michigan, August 2, 2004
- Damaging Wind and Heavy Rain in Florida, August 2, 2004
- Damaging Winds in Utah, August 2, 2004
- Hail and Damaging Wind in South Dakota, August 2, 2004
- Damaging Wind in Idaho, August 2, 2004
- Flash Flood in West Virginia, August 2, 2004
- Tornado in Tennessee, August 2, 2004
- Flash Flood in Washington, August 2, 2004
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: 5431585.