Enter any address in Williamson County, Tennessee to see its FEMA flood zone
Flash flooding from severe weather events is the primary flood concern in Williamson County. Between 2000 and 2020, NOAA Storm Events data recorded 73 flash flood events and 24 general flood events. For example, a major severe weather and flooding event occurred in February 2025, impacting Middle Tennessee with heavy rainfall and widespread flooding. Another instance on May 20, 2025, brought multiple rounds of thunderstorms, including large hail and tornadoes to the region.
National Flood Insurance Program (NFIP) claims data from Williamson County shows that properties in Zone A have experienced the most claims, with an average payout of $30,771 and an average water depth of 3.4 feet. Properties in Zone X also have a significant number of claims, with an average payout of $23,252 and an average water depth of 3.1 feet. Homeowners in Zone A, and those in other designated flood zones, should pay close attention to flood risk information.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
38 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Williamson County, Tennessee has recorded 97 flood-related events since 1996 according to NOAA's Storm Events Database, including 73 flash floods and 24 river or area floods. The county has received 16 federal disaster declarations, 1 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1974–2026)
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 |
| Severe Storms, Tornadoes, And Flooding | Tornado | Mar 25, 2021 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms, Flooding, Straight-line Winds, And Tornadoes | Severe Storm | Apr 30, 2010 |
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Severe Storm | Feb 5, 2008 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 4, 2003 |
| Severe Storms, Tornadoes And Flooding | Severe Storm | May 5, 1999 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | May 20, 2025 | 0.00K |
| Flash Flood | Feb 15, 2025 | 0.00K |
| Flash Flood | Apr 5, 2025 | 0.00K |
| Flash Flood | Apr 3, 2025 | 0.00K |
| Flood | Apr 3, 2025 | 0.00K |
| Flood | Aug 26, 2023 | 0.00K |
| Flood | Jul 19, 2023 | 0.00K |
| Flood | Dec 7, 2022 | 0.00K |
| Flash Flood | Mar 27, 2021 | 1.50M |
| Flash Flood | May 3, 2021 | 0.00K |
Flash Flood — May 20, 2025
Multiple rounds of thunderstorms impacted Middle Tennessee on May 20, 2025. The first round of thunderstorms was a decaying mesoscale convective system (MCS) that produced damaging winds which downed a few trees. The next round was discrete supercells which produced large hail, damaging winds, and tornadoes. The largest hail reported during this event was in Williamson County where hailstones o...
Flash Flood — Feb 15, 2025
A major severe weather and flooding event unfolded across Middle Tennessee on February 15-16, 2025. As well above average moisture spread into the area, this helped set the stage for very heavy rainfall across Middle Tennessee. Showers and thunderstorms began early during the day on February 15th, and the primary threat with this first round was flooding. The most significant flooding was repor...
Flash Flood — Apr 5, 2025
A major and historic multi-day severe weather event unfolded across Middle Tennessee during early April 2025. This event began during the afternoon hours of April 2nd and continued through April 6th. These first couple rounds of thunderstorms brought damaging winds and large hail along with a tornado risk. The corridor from southwest Middle Tennessee into the Nashville metro area was hit partic...
Flash Flood — Apr 3, 2025
A major and historic multi-day severe weather event unfolded across Middle Tennessee during early April 2025. This event began during the afternoon hours of April 2nd and continued through April 6th. These first couple rounds of thunderstorms brought damaging winds and large hail along with a tornado risk. The corridor from southwest Middle Tennessee into the Nashville metro area was hit partic...
Flood — Apr 3, 2025
A major and historic multi-day severe weather event unfolded across Middle Tennessee during early April 2025. This event began during the afternoon hours of April 2nd and continued through April 6th. These first couple rounds of thunderstorms brought damaging winds and large hail along with a tornado risk. The corridor from southwest Middle Tennessee into the Nashville metro area was hit partic...
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 Williamson 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 Williamson 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.