States › Tennessee › Williamson County
Williamson County, Tennessee
Recorded hazard history: storm events since 1950, federal disaster declarations since 1953, flood insurance claims since 1978, and FEMA's risk index.
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. NCEI storm records through 30 Jun 2026; OpenFEMA declarations refreshed 1 Oct 2026; NFIP claims as of 8 Sep 2026.
The NCEI record lists 915 events for Williamson County, Tennessee, between 1950 and 2026; damaging wind account for the largest share.
That is 157.0 events per 100 square miles, above the Tennessee figure of 112.2, and 35.8 per 10,000 residents against 66.4 statewide.
14 events fall in the 12 months to 30 Jun 2026. NCEI attributes 6 deaths and 23 injuries to events in the county, with property damage estimated at $59M and crop damage at $62K.
FEMA has designated the county in 16 federal disaster declarations since 1953; the most recent is Severe Winter Storm (major disaster, 6 Feb 2026).
National Flood Insurance Program policyholders in the county filed 1,103 claims since 1978, of which 936 were paid, totalling $31M (about $33K per paid claim). FEMA counts 1,284 residential flood policies in force.
FEMA's National Risk Index rates the county's overall risk as "Relatively Moderate" and its expected annual loss as "Relatively Moderate" ($98M a year across 18 hazards).
6 tropical storm or hurricane tracks in the HURDAT2 record passed within 100 miles of the county's centre at tropical-storm strength or more, 0 of them within 50 miles at hurricane strength.
Compared with Tennessee and the United States
| Measure | Williamson County | Tennessee | US |
|---|---|---|---|
| Recorded events since 1950 | 915 | 46,283 | 1,977,440 |
| Events per 100 square miles | 157.0 | 112.2 | 56.0 |
| Events per 10,000 residents | 35.8 | 66.4 | 59.6 |
| Events in the last 12 months | 14 | 1,524 | 62,008 |
| Deaths recorded by NCEI | 6 | 804 | 26,435 |
| Property damage (NCEI estimates) | $59M | $9.2B | $575B |
| NFIP claims per 1,000 residents | 4.3 | 2.5 | 8.1 |
| Average paid NFIP claim | $33K | $33K | $43K |
| Claims per 100 policies in force, last 10 years | 21.4 | 20.9 | 16.1 |
County-recorded events plus zone-recorded events whose forecast zone is named for the county. State and US rows include events recorded only by forecast zone. Rates use 2021 Census population and land area.
Events by decade
Trend: 700 events in the 20 years to 2025 against 188 in the 20 years before. Reporting practice changed in 1996 and again with automated reports in the 2000s, so decade totals measure the record as much as the weather.
Events by type
Hazard pages exist for hail, tornado, flood, wind and winter where the county has at least 10 recorded events. "Other" covers heavy rain, debris flow, dust, funnel clouds and similar reports.
Largest recorded events
| Date | Event type | Group | Magnitude | Property damage | Crop damage | Deaths | Injuries | Geography |
|---|---|---|---|---|---|---|---|---|
| 24 Dec 1988 | Tornado | Tornado | F4 | $25M | — | 1 | 7 | County |
| 1 May 2010 | Flash Flood | Flood | — | $50K | $1K | 1 | — | County |
| 12 Oct 2022 | Thunderstorm Wind | Wind | 58 mph | $10K | — | 1 | — | County |
| 11 Jun 2003 | Thunderstorm Wind | Wind | 69 mph | — | — | 1 | — | County |
| 27 Apr 2011 | Thunderstorm Wind | Wind | 63 mph | — | — | 1 | — | County |
| 3 May 2020 | Thunderstorm Wind | Wind | 64 mph | — | — | 1 | — | County |
| 26 Apr 2012 | Tornado | Tornado | EF0 | $75K | — | — | 6 | County |
| 30 Jul 2024 | Lightning | Lightning | — | $250K | — | — | 4 | County |
| 21 Apr 1972 | Tornado | Tornado | F1 | $250K | — | — | 3 | County |
| 8 Aug 2001 | Lightning | Lightning | — | — | — | — | 2 | County |
| 11 May 2003 | Tornado | Tornado | F3 | $2.2M | — | — | 1 | County |
| 2 May 2010 | Flood | Flood | — | $10M | $1K | — | — | County |
| 1 Mar 2017 | Tornado | Tornado | EF1 | $7.3M | — | — | — | County |
| 5 May 2003 | Tornado | Tornado | F1 | $3.0M | — | — | — | County |
| 24 Oct 2010 | Lightning | Lightning | — | $1.8M | — | — | — | County |
| 27 Mar 2021 | Flash Flood | Flood | — | $1.5M | — | — | — | County |
| 3 Mar 2023 | High Wind | Wind | 58 mph | $1.0M | — | — | — | Forecast zone |
| 3 May 2020 | Thunderstorm Wind | Wind | 70 mph | $703K | — | — | — | County |
| 5 May 1999 | Thunderstorm Wind | Wind | — | $476K | — | — | — | County |
| 13 Sep 2020 | Flash Flood | Flood | — | $400K | — | — | — | County |
Ranked by deaths, then injuries, then NCEI's damage estimate. Deaths and injuries are NCEI counts (direct plus indirect); no personal details are recorded here.
Federal disaster declarations
| Declared | Number | Type | Incident | Title | Programs |
|---|---|---|---|---|---|
| 6 Feb 2026 | DR-4898 | Major disaster | Winter Storm | Severe Winter Storm | Individual assistance, Public assistance |
| 24 Jan 2026 | EM-3635 | Emergency | Winter Storm | Severe Winter Storm | Public assistance |
| 2 Apr 2025 | EM-3625 | Emergency | Severe Storm | Severe Storms, Straight-Line Winds, Tornadoes, And Flooding | Public assistance |
| 8 May 2021 | DR-4601 | Major disaster | Tornado | Severe Storms, Tornadoes, And Flooding | Individual assistance, Public assistance |
| 2 Apr 2020 | DR-4514 | Major disaster | Biological | Covid-19 Pandemic | Individual assistance, Public assistance |
| 13 Mar 2020 | EM-3473 | Emergency | Biological | Covid-19 | Public assistance |
| 4 May 2010 | DR-1909 | Major disaster | Severe Storm | Severe Storms, Flooding, Straight-Line Winds, And Tornadoes | Individual assistance, Public assistance |
| 7 Feb 2008 | DR-1745 | Major disaster | Severe Storm | Severe Storms, Tornadoes, Straight-Line Winds, And Flooding | Individual assistance, Public assistance |
| 5 Sep 2005 | EM-3217 | Emergency | Hurricane | Hurricane Katrina Evacuation | Public assistance |
| 8 May 2003 | DR-1464 | Major disaster | Severe Storm | Severe Storms, Tornadoes, And Flooding | Individual assistance, Public assistance |
| 12 May 1999 | DR-1275 | Major disaster | Severe Storm | Severe Storms, Tornadoes And Flooding | Individual assistance, Public assistance |
| 20 Apr 1998 | DR-1215 | Major disaster | Severe Storm | Severe Storms, Tornadoes And Flooding | Individual assistance |
| 28 Feb 1994 | DR-1010 | Major disaster | Severe Storm | Severe Winter Ice Storm,Flash Flooding | Public assistance |
| 7 May 1979 | DR-585 | Major disaster | Severe Storm | Severe Storms, Tornadoes & Flooding | Individual assistance, Public assistance |
| 22 Mar 1975 | DR-459 | Major disaster | Flood | Severe Storms & Flooding | Individual assistance, Public assistance |
| 4 Apr 1974 | DR-424 | Major disaster | Tornado | Tornadoes | Individual assistance, Public assistance |
Declarations in which FEMA designated this county, from the OpenFEMA Disaster Declarations Summaries (v2). DR: major disaster; EM: emergency; FM: fire management assistance. Programs show whether individual or public assistance was made available.
Flood insurance claims
| Year of loss | Claims | Paid claims | Amount paid | Average paid |
|---|---|---|---|---|
| 2026 | 4 | 1 | $52,302 | $52,302 |
| 2025 | 4 | 3 | $84,541 | $28,180 |
| 2024 | 2 | 2 | $152,740 | $76,370 |
| 2023 | 1 | 0 | $0 | — |
| 2022 | 4 | 2 | $43,533 | $21,766 |
| 2021 | 198 | 180 | $8,311,947 | $46,177 |
| 2020 | 21 | 19 | $686,929 | $36,154 |
| 2019 | 10 | 8 | $80,654 | $10,082 |
| 2018 | 3 | 0 | $0 | — |
| 2017 | 28 | 22 | $454,554 | $20,662 |
| 2015 | 3 | 3 | $44,603 | $14,868 |
| 2013 | 14 | 14 | $200,169 | $14,298 |
| 2011 | 18 | 13 | $202,642 | $15,588 |
| 2010 | 439 | 395 | $18,199,757 | $46,075 |
| 2009 | 3 | 2 | $27,622 | $13,811 |
| 2008 | 2 | 1 | $4,903 | $4,903 |
| 2004 | 10 | 9 | $78,445 | $8,716 |
| 2003 | 60 | 53 | $617,672 | $11,654 |
| 2001 | 1 | 1 | $8,811 | $8,811 |
| 2000 | 14 | 12 | $68,724 | $5,727 |
| 1999 | 14 | 13 | $194,414 | $14,955 |
| 1998 | 36 | 31 | $231,068 | $7,454 |
| 1997 | 12 | 6 | $32,134 | $5,356 |
| 1996 | 2 | 0 | $0 | — |
| 1995 | 15 | 9 | $32,427 | $3,603 |
OpenFEMA NFIP claims (v3, as of 8 Sep 2026), aggregated by year of loss; amounts are building, contents and increased-cost-of-compliance payments as recorded. Repetitive-loss counts from the NFIP Multiple Loss Properties file (2 Aug 2026); policies in force from the NFIP Residential Penetration Rates file (3 Aug 2026).
National Risk Index
| Hazard (NRI) | Risk rating | Expected annual loss |
|---|---|---|
| Inland flooding | $56,972,085 | |
| Cold wave | $13,411,043 | |
| Tornado | $11,550,093 | |
| Earthquake | $8,483,524 | |
| Strong wind | $3,371,808 | |
| Heat wave | $1,777,140 | |
| Ice storm | $1,010,072 | |
| Winter weather | $468,932 | |
| Lightning | $467,821 | |
| Hail | $331,692 | |
| Drought | $77,213 | |
| Hurricane | $55,402 | |
| Wildfire | $44,664 | |
| Landslide | $3,157 |
FEMA National Risk Index, December 2025 release. Ratings are FEMA's relative comparison of counties; expected annual loss is FEMA's modelled estimate of average yearly building, population and agriculture loss. See how to read the NRI.
Hurricane and tropical storm passes
| Storm | Year | Closest approach | Max wind while within 100 mi |
|---|---|---|---|
| Frederic | 1979 | 48 mi | 46 mph |
| Audrey | 1957 | 61 mi | 40 mph |
| Unnamed Atlantic storm | 1934 | 87 mi | 40 mph |
| Unnamed Atlantic storm | 1915 | 62 mi | 40 mph |
| Unnamed Atlantic storm | 1892 | 86 mi | 40 mph |
| Unnamed Atlantic storm | 1888 | 65 mi | 58 mph |
HURDAT2 best-track positions at tropical-storm strength (34 kt) or more, measured from the county's Census centre point; through the 2025 season. Distance from a track is not the same as the extent of the storm's wind, rain or surge.
ZIP codes with flood claims
ZIP codes whose NFIP claims carry this county's code, with the number of claims. Five or more claims are needed for a ZIP page to be indexed.
Questions and answers
How often does it hail in Williamson County, TN?
NCEI records 197 hail events in Williamson County since 1950, in 39 different years; that is about 2.6 recorded events a year. 47 reports were golf-ball size (1.75 in) or larger.
Has Williamson County had a tornado?
Yes. NCEI records 26 tornadoes in Williamson County since 1950, 4 of them rated (E)F2 or stronger. Tornado deaths recorded: 1.
When was the last federal disaster declaration for Williamson County?
6 Feb 2026: Severe Winter Storm, a major disaster declaration for winter storm. The county appears in 16 declarations since 1953.
How many flood insurance claims have been filed in Williamson County, and how much was paid?
1,103 NFIP claims since 1978, 936 of them paid, for $31M in total. FEMA publishes these figures redacted and aggregated; individual properties are not identified.
Is Williamson County in the National Risk Index's high-risk band?
FEMA's National Risk Index (December 2025) rates the county "Relatively Moderate" for overall risk, "Relatively Moderate" for expected annual loss, "Very Low" for social vulnerability and "Very High" for community resilience. These ratings are FEMA's relative comparison across all US counties.
How does Williamson County compare with the rest of Tennessee?
157.0 recorded events per 100 square miles against 112.2 statewide, and 4.3 NFIP claims per 1,000 residents against 2.5. The comparison table on this page shows each measure beside the state and national figures.
Provenance
Storm events: NOAA NCEI Storm Events Database, yearly details files through 30 Jun 2026 (public domain). Declarations: OpenFEMA DisasterDeclarationsSummaries v2, refreshed 1 Oct 2026. Flood claims: OpenFEMA NfipClaims v3 as of 8 Sep 2026; NfipMultipleLossProperties v1 (2 Aug 2026); NfipResidentialPenetrationRates v1 (3 Aug 2026). Risk index: FEMA National Risk Index, December 2025. Hurricane tracks: NHC HURDAT2 through 2025. Population and area: US Census Bureau, 2021 vintage. Built 1 Oct 2026; see the methodology and corrections pages. Hazard hubs: Hail · Tornado · Flood · Wind · Winter.