Severe Weather History


Hazard archive · 1950 — present

Flash Flood in Montgomery County, Pennsylvania

192

Recorded events

9

Direct deaths

8

Direct injuries

$139.7M

Property damage

Flash Flood in Montgomery County, Pennsylvania: 192 recorded events between 1996 and 2025. The strongest on record measured 0. That places the county #47 nationally and #4 statewide for this hazard.

Decade by decade

Flash Flood in Montgomery County, Pennsylvania: events per decade

Flash Flood in Montgomery County, Pennsylvania: recorded events per decade
Flash Flood in Montgomery County, Pennsylvania: recorded events per decade

Reporting practice changed over time — early decades are undercounted, not calmer.

The busiest decade for flash flood in Montgomery County is the 2010s, when 72 of the county's 192 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 Montgomery County archive, flash flood makes up 17.2% of all recorded severe weather across 8 hazard types. Nationally the county sits at #47 for this hazard and #4 within Pennsylvania, putting it in the 98.5 percentile of all U.S. counties.

Seasonality

Events by month

2Jan
1Feb
4Mar
5Apr
11May
31Jun
48Jul
55Aug
23Sep
4Oct
7Nov
1Dec

Aug is the peak month for flash flood in Montgomery County with 55 recorded events, while Feb 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

DateLocationScaleDeathsInjuriesDamage
Sep 16, 1999COUNTYWIDE038$12.0M
Sep 1, 2021KING OF PRUSSIA020$20.0M
Sep 8, 1996SOUTHERN020$20.0M
Aug 4, 2020WORCESTER010$4K
Jun 16, 2001SOUTH PORTION010$33.5M
Source: NOAA/NCEI Storm Events · dates UTC

Most recent

Latest recorded events

DateLocationMagnitudeDamage
Jul 31, 2025PHILMONT COUNTRY CLU0$25K
Jul 31, 2025PHILMONT COUNTRY CLU0$25K
Jul 31, 2025BETHAYRES0$30K
Jul 14, 2025FRUITVILLE0$0
Jul 14, 2025POTTSTOWN0$0
Jul 10, 2025HARMONVILLE0$0
Jul 10, 2025SWEDELAND0$0
Jul 1, 2025FRUITVILLE0$0
May 31, 2025FRUITVILLE0$0
May 16, 2025SPRING MT0$0
Source: NOAA/NCEI Storm Events · dates UTC · recent entries may be preliminary

Other hazards here

More from Montgomery County

County overview →

From the record

What the reports say

Written by National Weather Service staff at the time of the event · public domain

Quick answers

Frequently asked

How many flash flood events are on record in Montgomery County, Pennsylvania?

192 flash flood events are recorded in Montgomery County between 1996 and 2025, causing 9 direct deaths.

What is the strongest flash flood recorded in Montgomery County?

The strongest flash flood on record in Montgomery County measured 0.

Where does the flash flood data for Montgomery 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 Montgomery County, Pennsylvania.” Severe Weather History. severeweatherhistory.com/county/pennsylvania/montgomery-county/flash-flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.


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