140
Recorded events
7
Direct deaths
0
Direct injuries
$8.5M
Property damage
Flash Flood in Union County, New Jersey: 140 recorded events between 1996 and 2025. The strongest on record measured 0. That places the county #87 nationally and #2 statewide for this hazard.
Decade by decade
Flash Flood in Union County, New Jersey: events per decade
Reporting practice changed over time — early decades are undercounted, not calmer.
The busiest decade for flash flood in Union County is the 2020s, when 60 of the county's 140 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 Union County archive, flash flood makes up 32.2% of all recorded severe weather across 8 hazard types. Nationally the county sits at #87 for this hazard and #2 within New Jersey, putting it in the 97.3 percentile of all U.S. counties.
Seasonality
Events by month
Jul is the peak month for flash flood in Union County with 50 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 2, 2021 | ELIZABETH | 0 | 4 | 0 | $0 |
| Jul 15, 2025 | PLAINFIELD | 0 | 2 | 0 | $0 |
| Sep 2, 2021 | KENILWORTH | 0 | 1 | 0 | $0 |
Most recent
Latest recorded events
| Date | Location | Magnitude | Damage |
|---|---|---|---|
| Aug 17, 2025 | NEW PROVIDENCE | 0 | $0 |
| Aug 13, 2025 | LINDEN ARPT | 0 | $0 |
| Jul 15, 2025 | PLAINFIELD | 0 | $0 |
| Jul 14, 2025 | SUMMIT | 0 | $0 |
| Jul 14, 2025 | CLARK | 0 | $0 |
| Jul 14, 2025 | SCOTCH PLAINS | 0 | $0 |
| Jul 14, 2025 | ROSELLE | 0 | $0 |
| Jul 14, 2025 | CRANFORD | 0 | $0 |
| Jul 14, 2025 | MOUNTAINSIDE | 0 | $0 |
| Jul 14, 2025 | SCOTCH PLAINS | 0 | $0 |
Other hazards here
More from Union County
- Thunderstorm Wind 178
- Flood 45
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Four people died due to flooding at the Oakwood Plaza apartment complex on Irvington Avenue in Elizabeth. All four people were found in one apartment and included a 74 year old woman, her 71 year old husband, their 38 year old son, and a 33 year old neighbor.
The Rahway River near Springfield rose above its minor flood stage of 7.0 feet at 8:30pm EDT. It then continued to rise, surpassing moderate flood stage (8.5 feet) at 9:15pm EDT and major flood stage (10.5 feet) at 11:45pm EDT before cresting at a height of 10.81 feet at 1:15am EDT on September 2nd. The crest of 10.81 feet is the second highest on record, behind only a crest of 10.88 feet in August 2011 associated with Tropical Storm Irene. The river then gradually fell through the overnight hours, eventually fallign back below minor flood stage at 12:45pm EDT on September 2nd.
Thunderstorms formed over Central New Jersey on the afternoon and evening of the 14th. The antecedent airmass featured tropical moisture. As the thunderstorms moved northward into Western Union County, they produced between 3 and 5 inches of rainfall in a relatively short period of time. A resident of Scotch Plains needed to be rescued from an SUV when the waters rapidly rose. In Fanwood, small streams swiftly overflowed onto property, causing minor damage.
Quick answers
Frequently asked
How many flash flood events are on record in Union County, New Jersey?
140 flash flood events are recorded in Union County between 1996 and 2025, causing 7 direct deaths.
What is the strongest flash flood recorded in Union County?
The strongest flash flood on record in Union County measured 0.
Where does the flash flood data for Union 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 Union County, New Jersey.” Severe Weather History. severeweatherhistory.com/county/new-jersey/union-county/flash-flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.