County Hazards

States › Tennessee › Johnson County › Flood

Flood in Johnson County, Tennessee

26 floods and flash floods events in the NCEI Storm Events record, 1950 to 2026. Event types counted: Flood, Flash Flood, Coastal Flood, Lakeshore Flood.

26 events · 1 deaths recorded · peak month July · county share of state 0.6%

2024-09-27: Flood2024-09-25: Flood2022-08-10: Flood2022-02-24: Flood2021-03-28: Flood2020-11-12: Flood2019-02-23: Flood2013-08-10: Flood2013-01-15: Flood2010-08-17: Flood2009-09-26: Flood
Flood event locations in and around Johnson County. Dots: Flood event locations in the kept record. Boundaries: US Census Bureau.

NCEI notes that Storm Data is compiled from a variety of sources including the National Weather Service, other federal, state and local agencies, the media and the public; that property and crop damage figures are estimates; and that some events are recorded by NWS forecast zone rather than by county. FEMA notes that NFIP claim records are redacted and aggregated to protect the privacy of policyholders. Storm records through 30 Jun 2026.

NCEI records 26 flood events in Johnson County, Tennessee, between 1950 and 2026, spread over 14 years.

July is the busiest month, with 7 of the recorded events. The last 20 years account for 11 events against 15 in the 20 years before, a change that reflects reporting practice as much as weather.

The county holds 0.6% of the 4,414 flood events recorded in Tennessee; its 8.7 per 100 square miles compares with 10.7 statewide.

NCEI attributes 1 death in the county to floods and flash floods.

Compared with Tennessee

MeasureJohnson CountyTennesseeUS
Flood events since 1950264,414183,559
Per 100 square miles8.710.75.2
Per 10,000 residents14.36.35.5
Deaths recorded11212,961
Busiest monthJulyFebruaryJune

By year

195019882026
Flood events recorded in Johnson County per year, 1950 to 2026 (2026 is partial).

Seasonality

Jan
2
Feb
5
Mar
2
Apr
1
May
1
Jun
0
Jul
7
Aug
4
Sep
3
Oct
0
Nov
1
Dec
0
Flood events in Johnson County by month of occurrence, all years.

Recorded events

All 26 events, most recent first. Magnitude is hail size, tornado rating or wind speed as recorded.

DateEvent typeMagnitudeProperty damageCrop damageDeathsInjuriesGeography
27 Sep 2024Flash Flood—$6.5M—1—County
25 Sep 2024Flash Flood—————County
10 Aug 2022Flash Flood—————County
24 Feb 2022Flash Flood—————County
28 Mar 2021Flash Flood—————County
12 Nov 2020Flood—————County
23 Feb 2019Flood—$900K———County
10 Aug 2013Flash Flood—$10K———County
15 Jan 2013Flood—$1K———County
17 Aug 2010Flash Flood—$10K———County
26 Sep 2009Flood—————County
31 Aug 2003Flash Flood—————County
10 Apr 2003Flood—————Forecast zone
21 Feb 2003Flood—————Forecast zone
16 Feb 2003Flash Flood—————County
14 Feb 2003Flood—$248K———Forecast zone
4 Jul 2002Flash Flood—————County
4 Jul 2002Flash Flood—————County
17 Mar 2002Flood—————Forecast zone
29 Jul 2001Flash Flood—————County
29 Jul 2001Flash Flood—————County
29 Jul 2001Flash Flood—————County
24 Jul 1999Flood—————County
11 Jul 1999Flash Flood—————County
7 Jan 1998Flash Flood—$500K———County
27 May 1997Flash Flood—$25K———County

Questions and answers

How many flood events has Johnson County had?

26 events in the NCEI Storm Events record between 1950 and 2026. Reporting of floods and flash floods became far more complete after 1996, so early decades undercount.

When was the last recorded flood event in Johnson County?

27 Sep 2024 (Flash Flood). Records reach NCEI about 120 days after the month ends.

What was the most damaging flood event recorded in Johnson County?

The flash flood of 27 Sep 2024, with property damage estimated by NCEI at $6.5M; 1 death recorded.

How does Johnson County compare with Tennessee for flood?

8.7 events per 100 square miles against 10.7 statewide; the county holds 26 of the state's 4,414 recorded events.

Provenance

NOAA NCEI Storm Events Database, yearly details files through 30 Jun 2026, public domain. County-recorded events plus zone-recorded events whose forecast zone is named for the county (marked "Forecast zone"). Population and area from the US Census Bureau (2021). Built 1 Oct 2026. See the methodology, the Flood hub and the county page.