Enter any address in Johnson County, Tennessee to see its FEMA flood zone
Flash flooding from heavy rainfall events dominates the flood character of Johnson County, TN. Recent examples include catastrophic flash flooding and river flooding associated with Tropical Storm Helene in September 2024, and flash flooding from slow-moving thunderstorms in August 2022.
The National Flood Insurance Program (NFIP) data shows a significant number of claims in Zone A, with an average payout of $52,117 and an average water depth of 1.6 feet. Claims in Zone X, while fewer, show a notably higher average payout of $52,416 with an average water depth of 30.9 feet. Homeowners in Zone A and those in Zone X should pay particular attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
4 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Johnson County, Tennessee has recorded 27 flood-related events since 1996 according to NOAA's Storm Events Database, including 17 flash floods and 9 river or area floods. The county has received 20 federal disaster declarations, 4 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1973–2026)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Winter Storm | Winter Storm | Jan 22, 2026 |
| Severe Storms, Straight-line Winds, Tornadoes, And Flooding | Severe Storm | Apr 2, 2025 |
| Tropical Storm Helene | Tropical Storm | Sep 26, 2024 |
| Severe Storms, Straight-line Winds, And Tornadoes | Severe Storm | Mar 31, 2023 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms, Flooding, Landslides, And Mudslides | Flood | Feb 19, 2019 |
| Severe Storms, Tornadoes, Straight-line Winds, And Associated Flooding | Severe Storm | Apr 25, 2011 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
| Severe Storms And Flooding | Severe Storm | Sep 16, 2004 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Sep 27, 2024 | 6.50M (1 deaths) |
| Flash Flood | Sep 25, 2024 | 0.00K |
| Flash Flood | Feb 24, 2022 | 0.00K |
| Flash Flood | Aug 10, 2022 | 0.00K |
| Flash Flood | Mar 28, 2021 | 0.00K |
| Flood | Nov 12, 2020 | 0.00K |
| Flood | Feb 23, 2019 | 900.00K |
| Flood | Jan 15, 2013 | 1.00K |
| Flash Flood | Aug 10, 2013 | 10.00K |
| Flash Flood | Aug 17, 2010 | 10.00K |
Flash Flood — Sep 27, 2024
Tropical Storm Helene caps off a several day heavy rainfall event in association with a stalled closed upper low that drew a stream of tropical moisture into the area on the 25th and 26th. The arrival of Helene on the 27th yielded catastrophic flash flooding and river flooding, as well as significant wind damage as wet soils and strong wind gusts led to forest damage.
Flash Flood — Sep 25, 2024
Tropical Storm Helene caps off a several day heavy rainfall event in association with a stalled closed upper low that drew a stream of tropical moisture into the area on the 25th and 26th. The arrival of Helene on the 27th yielded catastrophic flash flooding and river flooding, as well as significant wind damage as wet soils and strong wind gusts led to forest damage.
Flash Flood — Feb 24, 2022
A moist southwesterly flow aloft ran nearly parallel to a stalled cold front near east Tennessee on the 23rd. A surface low near Lake Charles LA would move up the boundary and produce a second round of rains on the 24th.
Flash Flood — Aug 10, 2022
High pressure over the area led to weak steering currents. Slow moving thunderstorms produced locally heavy rain.
Flash Flood — Mar 28, 2021
Thunderstorms with large hail spread northward across East Tennessee during the early morning hours of March 27, reaching southwest Virginia by late morning. These storms were associated with a warm front, which later stalled across northeast Tennessee. This stalled front was the focus of additional thunderstorms that produced damaging wind gusts and flooding in the evening of March 27 and into...
Source: NOAA National Weather Service Storm Events Database.
Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).
FEMA assigns flood zone designations to areas in Johnson County, Tennessee:
AE High Risk — 1% annual chance of flooding. Insurance required.
VE Very High Risk — Coastal flooding with wave action.
X (Shaded) Moderate Risk — 500-year floodplain.
X Low Risk — Outside major floodplains.
Properties in Johnson County, Tennessee that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.
Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.
Visit FloodSmart.gov to find an agent and get a quote.