147
Recorded events
0
Direct deaths
1
Direct injuries
$1.1B
Property damage
Flash Flood in Honolulu County, Hawaii: 147 recorded events between 1996 and 2026. The strongest on record measured 0. That places the county #76 nationally and #2 statewide for this hazard.
Decade by decade
Flash Flood in Honolulu County, Hawaii: events per decade
Reporting practice changed over time — early decades are undercounted, not calmer.
The busiest decade for flash flood in Honolulu County is the 2010s, when 71 of the county's 147 recorded events were logged. Comparing decades is useful for spotting active periods, but the earliest years are thin because systematic reporting for this hazard began later.
Within the Honolulu County archive, flash flood makes up 15.7% of all recorded severe weather across 13 hazard types. Nationally the county sits at #76 for this hazard and #2 within Hawaii, putting it in the 97.6 percentile of all U.S. counties.
Seasonality
Events by month
Mar is the peak month for flash flood in Honolulu County with 37 recorded events, while Jul is the quietest. Seasonality here is a property of the archive as much as the climate: reports cluster where population and spotter networks are densest.
Significant events
Deadliest on record
| Date | Location | Scale | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Dec 14, 2008 | HALEIWA | 0 | 0 | 1 | $0 |
Most recent
Latest recorded events
| Date | Location | Magnitude | Damage |
|---|---|---|---|
| Apr 10, 2026 | KAWELA BAY | — | $200K |
| Mar 23, 2026 | KAHUKU | — | $10.0M |
| Mar 20, 2026 | KAWELA BAY | — | $1.0B |
| Mar 13, 2026 | WAIPIO | — | $100K |
| Mar 12, 2026 | MAKAHA VALLEY | — | $0 |
| Mar 12, 2026 | SCHOFIELD BARRACKS | — | $20K |
| Mar 12, 2026 | WAIALUA | — | $40K |
| Mar 12, 2026 | WAIKANE | — | $50K |
| Feb 21, 2026 | FORT SHAFTER | — | $0 |
| Feb 21, 2026 | KAHUKU | — | $10.0M |
Other hazards here
More from Honolulu County
- Heavy Rain 567
- Flood 78
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Heavy rain fell over the Koolau mountain range in the middle to later half of the morning, then a thunderstorm developed and anchored itself over the mountains. This thunderstorm then produced a large amount of rain in a short time frame, quickly overwhelming Manoa Stream and sending a flood surge down towards Manoa Valley. Manoa marketplace had nearly 2 feet of water and parked cars were inundated. Homes in Manoa reported flooding and an excavation site quickly became overwhelmed with water and sent mud and debris down the road. The overflowing Manoa and Palolo Streams inundated the entire campus of Hokulani Elementary School in St. Louis Heights and students were evacuated. Large boulders and debris were observed across many roads in Manoa Valley and flooding was also observed across the upper portion of the University of Hawaii at Manoa campus. A home was also flooded in Laie.
Four feet of water from heavy rain flooded William Henry Road in Kaneohe in windward Oahu. A blocked drain caused the backup of water, inundating some homes in the area. Major flooding problems continued over windward portions of Oahu and the North Shore, especially around Haleiwa and Waialua. The Opaeula Stream overflowed at Haleiwa Road and caused flooding of homes in the area. Also in windward Oahu, flooding was reported along Okana Road and a partial road closure occurred on Kamehameha Highway between Wailehua Road and Waikane Store.
Traffic stalled in all lanes of Kalanianaole Highway in East Oahu near Niu Valley due to 10-12 inches of standing water on the roadway, and the water was still rising. Moments later, the roadway was closed from Aina Haina to Makapuu due to flooding.
Quick answers
Frequently asked
How many flash flood events are on record in Honolulu County, Hawaii?
147 flash flood events are recorded in Honolulu County between 1996 and 2026, causing 0 direct deaths.
What is the strongest flash flood recorded in Honolulu County?
The strongest flash flood on record in Honolulu County measured 0.
Where does the flash flood data for Honolulu County come from?
All events come from the NOAA/NCEI Storm Events Database, the federal public-domain archive of severe weather reports. Dates are UTC, damage is as reported and not inflation-adjusted, and the most recent entries may still be revised.
Cite this page
“Flash Flood in Honolulu County, Hawaii.” Severe Weather History. severeweatherhistory.com/county/hawaii/honolulu-county/flash-flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.