FEMA Records
4
Total declarations
Tennessee · FEMA + NOAA + National Risk Index
Williamson County, TN
4 FEMA disaster declarations (2021–2026), with a FEMA National Risk Index rating of Relatively Moderate. Most common hazard: Winter Storm.
- 4
- FEMA declarations
- 2
- Major disasters
- 85
- NRI risk · Relatively Moderate
- Winter Storm
- Top hazard
The verdict
Williamson County ranks in the riskiest 15% of U.S. counties for FEMA-modeled hazard risk, with more federally declared disasters than 57% of the 2,791 counties FEMA tracks. FEMA rates the county's overall risk as Relatively Moderate, based on 4 federal disaster declarations recorded since 2021, most often winter storm, 4% above the national county average of 4.
- Riskiest 15%
- of U.S. counties for FEMA National Risk Index score
- Relatively Moderate
- FEMA National Risk Index rating
- 4
- FEMA declarations vs 4 national county avg
- 2
- winter storm declarations, the most common hazard here
FEMA's National Risk Index score reflects expected annual loss, social vulnerability, and community resilience; the declaration count above reflects only Presidentially declared disasters, not every hazard event.
How does Williamson County compare?
Williamson County vs. every U.S. county
FEMA disaster declarations, all-time
4 Top 43% higher than 57% of 2,791 counties
Each bar is a band; taller bars hold more counties. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source FEMA Disaster Declarations Summaries v2 · 2026-07-25
Williamson County's FEMA Risk Index score
FEMA National Risk Index composite score vs. the Tennessee county average
How disaster-prone is Williamson County?
Declaration frequency
Williamson County, Tennessee has recorded 4 FEMA disaster declarations between 2021 and 2026, of which 2 were classified as Major Disaster declarations (DR) requiring federal individual and public assistance. That puts the county's average at 0.8 declarations per year across a 5-year record, or roughly 28% below the Tennessee county average of 5.6 and 4% above the national county average of 3.8. The dominant disaster type on record is Winter Storm, with 2 of 4 declarations falling under this category.
FEMA National Risk Index
This county sits among the highest-risk counties nationally on FEMA's National Risk Index, a composite score of 85.1/100 (Relatively Moderate). Expected Annual Loss is rated Relatively Moderate (roughly $98.0M in annualized losses). Social vulnerability reads Very Low and community resilience Very High, both critical modifiers of realized harm here. Of the 18 hazards FEMA models, Cold Wave stands out as the sharpest exposure here, rated Relatively High.
Flood exposure & the bottom line
Taken together, Williamson County reads as low relative risk on this historical lens, fewer federally recognized disasters than a typical U.S. county.
Risk Assessment
Risk Level
Low
vs. Tennessee Avg
-28%
State avg: 5.6
vs. National Avg
+4%
National avg: 3.8
Avg Per Year
0.8
Over 5 years
FEMA NRI 8-hazard radar - Williamson County
How to read this radar
The radar plots Williamson County's relative exposure to the eight headline natural hazards used by the FEMA National Risk Index. Each axis is the qualitative NRI risk rating (Very Low through Very High) re-expressed on a 0-100 scale so that the polygon shape lets you compare a county against another at a glance. A rounder polygon means broad multi-hazard exposure; a spiky polygon means one or two dominant hazards drive most of the modeled risk.
NRI Source
FEMA 2023
Latest NRI release
County FIPS
47187
TN state code
Source: FEMA National Risk Index FEMA National Risk Index Per-county per-hazard ratings, 2023 release
Disaster Types
Winter Storm 2
Severe Storm 1
Tornado 1
Declaration Types
What DR / EM / FM mean
FEMA categorizes declarations as Major Disasters (DR), Emergencies (EM), or Fire Management Assistance (FM).
Major Disaster - 2 50.0%
of all 4 declarations
Emergency - 2 50.0%
of all 4 declarations
FEMA Declarations Timeline
| Year | Declarations | |
|---|---|---|
| 2026 | 2 | |
| 2025 | 1 | |
| 2021 | 1 | |
Disaster Declarations
| DR# | Title | Type | Incident | Date |
|---|---|---|---|---|
| 4898 | SEVERE WINTER STORM | DR | Winter Storm | 2026-02-06 |
| 3635 | SEVERE WINTER STORM | EM | Winter Storm | 2026-01-24 |
| 3625 | SEVERE STORMS, STRAIGHT-LINE WINDS, TORNADOES, AND FLOODING | EM | Severe Storm | 2025-04-02 |
| 4601 | SEVERE STORMS, TORNADOES, AND FLOODING | DR | Tornado | 2021-05-08 |
Storm Events in Tennessee
| Storm Type | Events | Fatalities | Injuries | Property Damage |
|---|---|---|---|---|
| Thunderstorm Wind | 7,667 | 25 | 63 | $114.4M |
| Hail | 2,202 | 0 | 0 | $655.5K |
| Heat | 1,980 | 11 | 30 | $0 |
| Flash Flood | 1,564 | 57 | 3 | $349.7M |
| Winter Weather | 1,303 | 5 | 0 | $266.0K |
Source: NOAA Storm Events Database NOAA Storm Events Database State-level aggregated data, 2015–2025
FEMA National Risk Index
Overall Risk
Relatively Moderate
Score: 85.1/100
Expected Annual Loss
Relatively Moderate
$98.0M/year
Social Vulnerability
Very Low
Community Resilience
Very High
Hazard Risk Breakdown
Cold Wave Relatively High
Earthquake Relatively Low
Strong Wind Relatively High
Tornado Relatively Moderate
Winter Weather Relatively Moderate
Ice Storm Relatively High
Heat Wave Relatively Low
Landslide Very Low
Lightning Relatively Low
Hail Relatively Low
Hurricane Very Low
Wildfire Very Low
Drought Relatively Low
Source: FEMA National Risk Index (NRI) FEMA National Risk Index (NRI) Ratings reflect relative scores among all US counties. Data: hazards.fema.gov/nri
Counties with Similar Risk in Tennessee
Disaster Preparedness Guides
Related
Frequently Asked Questions
How many natural disasters has Williamson County, Tennessee had?
Williamson County, Tennessee has received 4 FEMA disaster declarations from 2021 to 2026. Of these, 2 were major disaster declarations.
What is the most common disaster type in Williamson County?
The most common disaster type in Williamson County is Winter Storm, with 2 declarations. Other disaster types include Severe Storm (1), Tornado (1).
How does Williamson County's disaster risk compare to the Tennessee average?
Williamson County has 4 disaster declarations, which is 28% lower than the Tennessee county average of 5.6 declarations. Compared to the national county average of 3.8, it is 4% higher.
How many major FEMA disaster declarations has Williamson County received?
Williamson County has received 2 major disaster declarations, representing 50% of all 4 disaster declarations. Major disaster declarations typically involve significant damage requiring federal assistance.
What types of storms are most common in Tennessee?
The most common storm types in Tennessee include Thunderstorm Wind (7,667 events), Hail (2,202 events), Heat (1,980 events). NOAA storm event data covers severe weather from 2015 to 2025.
What was the worst year for disasters in Williamson County?
The most active year for disaster declarations in Williamson County was 2026, with 2 declarations. The county has FEMA disaster data spanning 2021 to 2026.
What is the overall disaster risk level for Williamson County?
Williamson County's 4 FEMA disaster declarations put it in the low-risk band, fewer federally recognized disasters than a typical U.S. county over the same span.
What is the FEMA National Risk Index score for Williamson County?
According to the FEMA National Risk Index, Williamson County, Tennessee has an overall risk score of 85.1 out of 100 (Relatively Moderate). The county's social vulnerability rating is Very Low and community resilience is Very High. The Expected Annual Loss (EAL) score is Relatively Moderate, representing $98.0M in annualized losses.
Which natural hazard poses the greatest risk to Williamson County?
Based on FEMA NRI data, the highest-risk natural hazard in Williamson County is Cold Wave (risk rating: Relatively High). Other significant hazards include Earthquake (Relatively Low) and Strong Wind (Relatively High). These scores are based on FEMA's analysis of historical event frequency, exposed assets, and community vulnerability.
Data Sources & Methodology
Disaster declaration data comes from the FEMA OpenFEMA Disaster Declarations Summaries v2 API, which includes all federally declared disasters, emergencies, and fire management assistance grants.
Storm event data is sourced from the NOAA Storm Events Database (2015–2025), which tracks significant weather events including thunderstorms, tornadoes, floods, and winter storms.
This data is provided for informational purposes only. FEMA disaster declarations represent federal response actions and may not capture all local emergencies or weather events.
What this means for Williamson County
Williamson County, TN runs 28% below the Tennessee county average for federal disaster declarations (4 vs 6), a low historical load overall.
- Its most common federal declaration type is major disaster (2 of 4) - know the hazards most likely here before they happen. Tennessee overview
- See how this county ranks against the rest of the country for disaster frequency. Most-disaster rankings
- Read how to read FEMA declarations, NRI risk scores, and what they do and don't tell you. Disaster-data guide
Historical declaration counts describe past federal response, not a forecast. For current threats, follow the National Weather Service and local officials; in an emergency call 911.
According to the Federal Emergency Management Agency, this profile draws on 2,791 tracked U.S. counties in FEMA's Disaster Declarations Summaries dataset, refreshed as of 2026-07-25. Read our methodology - how this data is sourced, computed, and verified.
All federal data sources used on this page
- FEMA OpenFEMA, Disaster Declarations Summaries v2 - all federally-declared disasters for this county. fema.gov/openfema/disaster-declarations
- FEMA National Risk Index (NRI) - per-county per-hazard risk ratings and expected annual loss. hazards.fema.gov/nri
- NOAA NCEI Storm Events Database - state-level storm/severe-weather event records, 2015–2025. ncdc.noaa.gov/stormevents
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainHazard Editorial
Verify with FEMA → · Verify with FEMA NRI → · Verify with NOAA →
Every figure on PlainHazard is rendered directly from FEMA federal disaster data, no number is typed in by an editor. This page draws directly on FEMA federal disaster data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or national statistics report, or report a data error.