Chester County, SC
FEMA National Risk Index scores, disaster declarations & hazard data
Chester County has experienced 23 federally declared disasters since 1977, most recently Severe Winter Storm in 2026. Its overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Chester County's highest-rated hazards are ice storm, lightning, and tornado, with its top risk rated "Relatively High" by FEMA's National Risk Index. Community vulnerability is elevated (70th percentile nationally), suggesting residents may face greater difficulty recovering from major disasters.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Chester County has been designated in 23 declarations since 1977, covering 7 disaster types including hurricane (12), severe storm (3), biological (2).
| Year | Type | Event name |
|---|---|---|
| 2026 | Winter Storm | Severe Winter Storm |
| 2024 | Hurricane | Hurricane Helene |
| 2024 | Tropical Storm | Hurricane Helene |
| 2024 | Tropical Storm | Hurricane Debby |
| 2023 | Hurricane | Hurricane Idalia |
| 2023 | Hurricane | Hurricane Ian |
| 2022 | Hurricane | Hurricane Ian |
| 2020 | Severe Storm | Severe Storms, Tornadoes, Straight-Line Winds, And Flooding |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
Showing the 10 most recent of 23 total declarations since 1977.
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Very Low | 45.5 | 0 | 0 | — |
| Inland Flooding | Relatively Low | 41.7 | 1 | 0 | $50K |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively Low | 71.3 | — | — | — |
| Heat Wave | Relatively Low | 41.2 | 0 | 0 | — |
| Tornado | Relatively Moderate | 74.5 | 4 | 0 | $125K |
| Hurricane | Relatively Low | 63.9 | 0 | 0 | — |
| Hail | Very Low | 30 | 9 | 0 | — |
| Strong Wind | Relatively Moderate | 64.4 | 0 | 0 | — |
| Winter Weather | Very Low | 21.2 | 0 | 0 | — |
| Ice Storm | Relatively High | 82.3 | — | — | — |
| Cold Wave | Relatively Moderate | 66.8 | — | — | — |
| Lightning | Relatively Moderate | 76.4 | 1 | 1 | — |
| Drought | Relatively Low | 40.8 | 0 | 0 | — |
| Landslide | Very Low | 41.4 | 0 | 0 | — |
| Avalanche | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic Activity | Not Applicable | — | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
Chester County ranks in the 70th percentile (Moderate) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 70th | Moderate |
| Socioeconomic status | 81st | High |
| Household characteristics | 38th | Low |
| Racial & ethnic minority status | 80th | High |
| Housing type & transportation | 53rd | Moderate |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 56th | Relatively Moderate |
| Risk to homes | 52nd | Relatively Moderate |
| Buildings in direct exposure zone | 82.6% | — |
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in Chester County?
According to the FEMA National Risk Index, the highest-risk hazards in Chester County, South Carolina are ice storm, lightning, and tornado. The county's overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Has Chester County received federal disaster declarations?
Yes. Chester County has received 23 federal disaster declarations since 1977, including declarations in 2026. The most common disaster type on record is hurricane (12 declarations).
Has Chester County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for Chester County include Severe Winter Storm (2026), Hurricane Helene (2024), Hurricane Helene (2024), Hurricane Debby (2024). See the declarations table above for the full history since 1977.
How does Chester County's natural hazard risk compare to nearby counties?
Among neighboring counties, York County, SC has the highest overall natural hazard risk (Relatively Moderate) and Fairfield County, SC has the lowest (Very Low). Chester County is rated Relatively Low overall.
How is Chester County's composite disaster risk index calculated?
Chester County's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. Chester County's composite score of 43 means its overall natural hazard risk is higher than 43% of US counties.