81
Recorded events
1
Direct deaths
1
Direct injuries
$7.5M
Property damage
Flash Flood in Rockland County, New York: 81 recorded events between 1996 and 2025. The strongest on record measured 0. That places the county #268 nationally and #17 statewide for this hazard.
Decade by decade
Flash Flood in Rockland County, New York: events per decade
Reporting practice changed over time — early decades are undercounted, not calmer.
The busiest decade for flash flood in Rockland County is the 2020s, when 29 of the county's 81 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 Rockland County archive, flash flood makes up 25.4% of all recorded severe weather across 9 hazard types. Nationally the county sits at #268 for this hazard and #17 within New York, putting it in the 91.4 percentile of all U.S. counties.
Seasonality
Events by month
Jul is the peak month for flash flood in Rockland County with 25 recorded events, while Jan 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 |
|---|---|---|---|---|---|
| Sep 16, 1999 | COUNTYWIDE | 0 | 1 | 0 | $4.4M |
| Jun 23, 2001 | SUFFERN | 0 | 0 | 1 | $0 |
Most recent
Latest recorded events
| Date | Location | Magnitude | Damage |
|---|---|---|---|
| Jul 14, 2025 | NANUET | 0 | $0 |
| Jul 14, 2025 | MONSEY | 0 | $0 |
| Jul 14, 2025 | SPRING VLY ARPT | 0 | $0 |
| Jul 14, 2025 | AIRMONT | 0 | $0 |
| Jul 14, 2025 | GERMONDS | 0 | $0 |
| Jul 14, 2025 | GERMONDS | 0 | $0 |
| Jul 14, 2025 | SUFFERN | 0 | $0 |
| Jul 14, 2025 | MONSEY HGTS | 0 | $0 |
| Jul 14, 2025 | NANUET | 0 | $0 |
| Jul 14, 2025 | NANUET | 0 | $0 |
Other hazards here
More from Rockland County
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Flash flooding resulted in an estimated $3,126,485 in damages across Rockland County. This estimate is based on FEMA grant money awarded under the Individuals and Household Program (IHP), which includes funds for both housing assistance and other needs.
The Mahwah River near Suffern rose above its minor flood stage of 5.0 feet at 10:30pm EDT. It then continued to rise, surpassing moderate flood stage (7.0 feet) and cresting at a height of 7.06 feet at 12:30am EDT on September 2nd. The river then gradually fell through the overnight hours, receding below minor flood stage by 10:45am EDT on September 2nd.
Numerous roads were flooded in Nanuet. The intersection of North Middletown Rd. and Atlantic Ave. in Nanuet was closed at 5:40 EDT due to flooding. Germonds Road in Clarkstown (Rockland Lake) was also closed due to flooding.
Quick answers
Frequently asked
How many flash flood events are on record in Rockland County, New York?
81 flash flood events are recorded in Rockland County between 1996 and 2025, causing 1 direct deaths.
What is the strongest flash flood recorded in Rockland County?
The strongest flash flood on record in Rockland County measured 0.
Where does the flash flood data for Rockland 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 Rockland County, New York.” Severe Weather History. severeweatherhistory.com/county/new-york/rockland-county/flash-flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.