99
Recorded events
0
Direct deaths
1
Direct injuries
$52.5M
Property damage
Flash Flood in Northampton County, Pennsylvania: 99 recorded events between 1996 and 2025. The strongest on record measured 0. That places the county #168 nationally and #14 statewide for this hazard.
Decade by decade
Flash Flood in Northampton County, Pennsylvania: events per decade
Reporting practice changed over time — early decades are undercounted, not calmer.
The busiest decade for flash flood in Northampton County is the 2010s, when 34 of the county's 99 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 Northampton County archive, flash flood makes up 14.1% of all recorded severe weather across 9 hazard types. Nationally the county sits at #168 for this hazard and #14 within Pennsylvania, putting it in the 94.6 percentile of all U.S. counties.
Seasonality
Events by month
Jul is the peak month for flash flood in Northampton County with 29 recorded events, while Apr 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 |
|---|---|---|---|---|---|
| May 19, 2000 | CENTRAL PORTION | 0 | 0 | 1 | $0 |
Most recent
Latest recorded events
| Date | Location | Magnitude | Damage |
|---|---|---|---|
| Jul 3, 2025 | NAZARETH | 0 | $0 |
| Jul 3, 2025 | ULHERS | 0 | $0 |
| Jul 3, 2025 | BUTZTOWN | 0 | $0 |
| Jul 3, 2025 | EASTON ARPT | 0 | $0 |
| Jul 3, 2025 | WASSERGASS | 0 | $0 |
| Aug 19, 2024 | NEWBURG | 0 | $50K |
| Aug 7, 2024 | SANDTS EDDY | 0 | $20K |
| Jul 16, 2023 | EASTON | 0 | $0 |
| Jul 16, 2023 | MARTINS CREEK | 0 | $0 |
| Jul 16, 2023 | KEPLERS MILL | 0 | $0 |
Other hazards here
More from Northampton County
- Thunderstorm Wind 389
- Hail 69
- Lightning 60
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
The heavy rain caused flooding of roadways and small streams in southern parts of Northampton County and affected Bethlehem and Lower Saucon Township the most. In Bethlehem, flooding along the Monocacy Creek inundated historical buildings in the Colonial Industrial Quarter. The flooding was exacerbated by debris that accumulated under a nearby bridge which acted like a dam. Four feet of water and mud accumulated in the 1776 Tannery and 1762 Waterworks. Old wooden pieces of Luckenbach Mill were also damaged. The flooding overturned tannery benches and furniture and literally knocked a few doors of their hinges. The water damaged mortar and plaster walls. Chunks of blacktop were also ripped from the parking lot. The event total at Lehigh Valley International Airport was 2.30 inches.
Major flooding was reported on several roadways in and near downtown Bethlehem. The southbound side of Pennsylvania Route 378 was closed between 3rd Avenue and 8th Avenue. Vehicles were stranded on Route 378. A basement was flooded on the 1600 Broadway along with water rescues at 33rd and Lehigh streets. Motorists were also stranded due to flood waters in Lower Macungie twp and in Allentown.
In addition to the severe weather, torrential downpours caused flash flooding in Northampton Borough as the Dry Run flooded. On Banks Street, about 12 to 14 homes were flooded. Gasoline was also released into the flood waters. Flash flooding extended to East 8th Street where one home suffered structural damage and two people were trapped inside. The family was displaced and assisted by the Red Cross. Doppler radar storm total estimates reached around two inches.
Quick answers
Frequently asked
How many flash flood events are on record in Northampton County, Pennsylvania?
99 flash flood events are recorded in Northampton County between 1996 and 2025, causing 0 direct deaths.
What is the strongest flash flood recorded in Northampton County?
The strongest flash flood on record in Northampton County measured 0.
Where does the flash flood data for Northampton 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 Northampton County, Pennsylvania.” Severe Weather History. severeweatherhistory.com/county/pennsylvania/northampton-county/flash-flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.