91
Recorded events
6
Direct deaths
1
Direct injuries
$50.7M
Property damage
Flash Flood in Frederick County, Maryland: 91 recorded events between 1996 and 2025. The strongest on record measured 0. That places the county #209 nationally and #5 statewide for this hazard.
Decade by decade
Flash Flood in Frederick County, Maryland: events per decade
Reporting practice changed over time — early decades are undercounted, not calmer.
The busiest decade for flash flood in Frederick County is the 2010s, when 42 of the county's 91 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 Frederick County archive, flash flood makes up 8.5% of all recorded severe weather across 10 hazard types. Nationally the county sits at #209 for this hazard and #5 within Maryland, putting it in the 93.2 percentile of all U.S. counties.
Seasonality
Events by month
Sep is the peak month for flash flood in Frederick County with 29 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
| Date | Location | Scale | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Jun 27, 2006 | COUNTYWIDE | 0 | 5 | 1 | $500K |
| Jun 19, 1996 | N PORTION | 0 | 1 | 0 | $5.0M |
Most recent
Latest recorded events
| Date | Location | Magnitude | Damage |
|---|---|---|---|
| Jul 31, 2025 | NEW MARKET | 0 | $0 |
| May 6, 2025 | BROAD RUN | 0 | $0 |
| Aug 30, 2024 | FREDERICK | 0 | $0 |
| Sep 23, 2021 | WALKERSVILLE | 0 | $0 |
| Sep 23, 2021 | JOHNSVILLE | 0 | $0 |
| Sep 23, 2021 | LIBERTYTOWN | 0 | $0 |
| Sep 23, 2021 | NEW MIDWAY | 0 | $0 |
| Sep 9, 2021 | FREDERICK | 0 | $0 |
| Sep 1, 2021 | THURMONT | 0 | $0 |
| Sep 1, 2021 | FEAGAVILLE | 0 | $0 |
Other hazards here
More from Frederick County
- Thunderstorm Wind 617
- Flood 194
- Hail 86
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Significant flash flooding occurred during the evening of May 15th from the city of Frederick southwestward toward Braddock Heights and Jefferson. The amount of damage shown here is total damage not already accounted for in other reports.
Floodwaters were more than two feet deep on North Market Street near the Frederick YMCA. Water entered buildings in the area and several parked cars were mostly submerged in water. The YMCA building itself had water enter the building with an estimated 40,000 sqft of the 95,000 sqft facility suffering water damage.
Multiple reports of flooding in Frederick Maryland. These reports include road closures at the 500 block of West Patrick Street, Market Street at South Street, Stauffer Road at Israel Creek and English Muffin Way at Lime Kiln Way. Also, flooding was reported at Frederick High School, Lincoln Elementary School and Thomas Johnson High School.
Quick answers
Frequently asked
How many flash flood events are on record in Frederick County, Maryland?
91 flash flood events are recorded in Frederick County between 1996 and 2025, causing 6 direct deaths.
What is the strongest flash flood recorded in Frederick County?
The strongest flash flood on record in Frederick County measured 0.
Where does the flash flood data for Frederick 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 Frederick County, Maryland.” Severe Weather History. severeweatherhistory.com/county/maryland/frederick-county/flash-flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.