Hamilton County, Tennessee

What hazards hit Hamilton County most?

The most frequent records are severe thunderstorm wind events: 501 since 1956. 47% of its severe thunderstorm wind events since 1956 fell in June and July. The rank column places the county among Tennessee's counties by days with a record per 1,000 square miles of land over each hazard's complete period.

Source: NOAA NCEI Storm Events Database (county and forecast-zone records attributed to the county; a zone record shows its own totals on each county it covers). Days: dates with at least one record of the hazard in the county. Ranks: days with a record per 1,000 square miles of land (Census Bureau 2024 Gazetteer), since 1950 for tornadoes, 1955 for hail and thunderstorm wind, 1996 for the rest.

How many tornadoes has Hamilton County had?

NOAA records 27 tornadoes in Hamilton County from 1974 to 2023, the strongest rated EF4, with 11 deaths and 207 injuries recorded in the county. A tornado that crossed a county line is counted in each county it touched, with the length of its path inside the county.

Counted as whole tornadoes rather than county records, the Storm Prediction Center's database holds 29 tornadoes whose track touched Hamilton County since 1950 (NOAA's county records number 27: they file a crossing tornado once per county segment, and the two databases differ on some tracks); along their whole tracks they killed 24 people, 11 of them in Hamilton County.

Map of the strongest tornado tracks in Tennessee.

Source: NOAA NCEI Storm Events Database, tornado records by county (path length in the county, maximum width); ratings as published: F scale before February 1, 2007, EF scale after. Whole-track figures: NOAA Storm Prediction Center tornado database (1950-2025). SPC severe weather database.

When was the last damaging storm in Hamilton County?

The most recent record with damage, injuries or deaths is the June 22, 2026 thunderstorm wind ($2.4 million in damage in 2025 dollars).

Significant electrical infrastructure damage in southern Chattanooga as the storm passed through southern Hamilton County. Local media cited more than 260 instances of damage to electrical wires, poles, and related power infrastructure. Damages reached over $2 million.
National Weather Service event narrative, NOAA Storm Events Database (search the full record, event 1353113)

Source: NOAA NCEI Storm Events Database; every record of 2025-2026 is listed, earlier ones when they caused deaths, injuries or $250,000 of damage (2025 dollars), and every tornado.

The deadliest and costliest records

Source: NOAA NCEI Storm Events Database: deaths and injuries direct and indirect; damage is property plus crops as estimated by the National Weather Service, converted to 2025 dollars.

Is it getting more frequent?

Records per decade for Hamilton County's most frequent hazards. Counts rose everywhere after 1996, when NOAA began recording every event type, so compare decades within a hazard's complete period only (the shaded cells come before it).

Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).

What time of year?

47% of its severe thunderstorm wind events since 1956 fell in June and July. The two busiest months are in violet.

Source: NOAA NCEI Storm Events Database, records by the month they began.

Federal disaster declarations for Hamilton County

FEMA's register lists 25 declarations that include Hamilton County: 18 major disasters, 5 emergencies and 2 fire management assistance declarations. Most were for severe storm (11) and flood (5).

Source: FEMA OpenFEMA Disaster Declarations Summaries (v2), declarations through October 2, 2026; one declaration is counted once however many areas it names. OpenFEMA dataset page.

How many floods has Hamilton County had?

NOAA's Storm Events Database holds 85 flood or flash flood records for Hamilton County from 1996 to 2026, on 63 days, with 3 deaths. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Hamilton County ranks 207th of 2,942 U.S. counties.

The National Flood Insurance Program has paid $30.3 million on 1,748 claims filed in Hamilton County; the most in one year was 304 in 2003. Claims count insured losses only: uninsured flood damage is not in this file.

Source: FEMA OpenFEMA NFIP Redacted Claims, as of September 8, 2026; claims by year of loss, payments in the dollars of the year paid. OpenFEMA dataset page.

FEMA's modeled risk for Hamilton County

FEMA's National Risk Index rates Hamilton County Relatively Moderate overall, with an expected annual loss of $140 million. These are FEMA's model estimates of future loss from 18 hazards, not a count of what happened; they can differ from the record above.

Source: FEMA National Risk Index, county table, December 2025 release. FEMA's National Risk Index map.

Counties that share a border with Hamilton County

1. Hamilton County 868
2. Whitfield County, GA 509
3. Bradley County 501
4. Walker County, GA 438
5. Marion County 422
6. Dade County, GA 380
7. Rhea County 374
8. Catoosa County, GA 353
9. Bledsoe County 333
10. Sequatchie County 279
11. Meigs County 237

Source: U.S. Census Bureau county adjacency file; NOAA NCEI Storm Events Database, records since 1950. The Census Bureau's adjacency file.

Next

• Tornadoes in TennesseeEvery Tennessee tornado since 1950 and the counties with the most per square mile
• Severe thunderstorm wind in TennesseeThe state's severe thunderstorm wind events, by county, year and month
• The Tennessee recordEvery hazard in the state, its deadliest events and its federal declarations
• FEMA's risk rating for each hazard in Hamilton CountyThe hazard risk calculator: 18 hazards beside the county's record
• Download Hamilton County's FEMA declarations (CSV)25 rows: every declaration that named the county, for your own analysis