Marion County, South Carolina Natural Disaster Risk
FEMA National Risk Index assessment · SC
LowComposite Risk Score
National percentile: 81th
Marion County faces low composite natural disaster risk (NRI Risk Index score 80.7, 81th national percentile), driven primarily by hurricane and cold wave exposure. Expected annual loss across all 18 hazard types is $27M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Marion County at low composite risk, with a National Risk Index score of 80.7 out of 100 — placing it in the 81st national percentile and below the national average for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Most of Marion County's expected losses come from hurricane (tropical cyclones bringing extreme wind, rain, and storm surge) at High risk — $13M in expected annual loss and about 0.27 events per year; cold wave (prolonged spells of dangerously low temperatures) at High risk — $5M in expected annual loss and about 0.47 events per year; and earthquake (ground shaking from sudden movement along geologic faults) at Low risk — $1M in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $27M in expected annual loss for a population of 29K.
Beyond physical exposure, Marion County has a very high social vulnerability rating (how susceptible the population is to harm) and a low community resilience rating (its capacity to prepare for and recover from disasters). That combination — a more vulnerable population with limited resilience — can amplify the human cost of any given event.
The county's disaster history tells the same story: Marion County has received 28 federal disaster declarations since 1989, including 16 for hurricane events and 3 for severe ice storm events. The most recent was Severe Winter Storm (winter storm), declared in January 2026.
Among 46 South Carolina counties, Marion County ranks #21 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Hurricane | High | 0.27 / yr | $13M |
| Cold Wave | High | 0.47 / yr | $5M |
| Earthquake | Low | 0.00 / yr | $1M |
| Tornado | Medium | 0.26 / yr | $2M |
| Ice Storm | Medium | 0.76 / yr | $159K |
| Wildfire | Low | 0.00 / yr | $99K |
| Heat Wave | Low | 9.11 / yr | $501K |
| Lightning | Medium | 58.22 / yr | $279K |
| Strong Wind | Medium | 3.55 / yr | $479K |
| Riverine Flood | Low | 0.64 / yr | $5M |
| Hail | Low | 3.14 / yr | $182K |
| Winter Weather | Low | 1.58 / yr | $33K |
| Drought | Low | 15.00 / yr | $29K |
| Coastal Flood | Very Low | 0.01 / yr | $14 |
| Landslide | Very Low | 0.09 / yr | $30 |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Marion County has received 28 federal disaster declarations since 1989, most recently Severe Winter Storm in January 2026. Most frequent causes: Hurricane (16), Severe Ice Storm (3), Tropical Storm (2).
| Declared | Type | Disaster |
|---|---|---|
| January 2026 | Winter Storm | Severe Winter Storm |
| September 2024 | Tropical Storm | Hurricane Helene |
| August 2024 | Tropical Storm | Hurricane Debby |
| August 2023 | Hurricane | Hurricane Idalia |
| November 2022 | Hurricane | Hurricane Ian |
| September 2022 | Hurricane | Hurricane Ian |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2019 | Hurricane | Hurricane Dorian |
| September 2019 | Hurricane | Hurricane Dorian |
Showing the 10 most recent of 28 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Marion County?
Marion County has a composite FEMA National Risk Index score of 80.7 out of 100, placing it in the Low category and the 81th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Marion County?
The three highest-rated hazards are Hurricane (High, $13M EAL), Cold Wave (High, $5M EAL), Earthquake (Low, $1M EAL). These account for most of the county's expected annual losses.
How does Marion County compare to other South Carolina counties?
Marion County ranks #21 of 46 South Carolina counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Marion County had?
FEMA records 28 federal disaster declarations for Marion County since 1989, most often 16 for hurricane events and 3 for severe ice storm events. The most recent was Severe Winter Storm, declared in January 2026.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. Marion County's $27M EAL is a statistical average, not a guarantee for any specific year or address.