Calhoun County, IA
FEMA National Risk Index scores, disaster declarations & hazard data
Calhoun County has experienced 18 federally declared disasters since 1979, most recently Severe Storms, Tornadoes, And Flooding in 2024. Its overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Calhoun County's highest-rated hazards are drought, hail, and tornado, with its top risk rated "Relatively High" by FEMA's National Risk Index. Recorded storm events have decreased 32% over the past five years compared to the prior five-year period. Community vulnerability is relatively low (9th percentile nationally), indicating stronger recovery capacity than most US counties.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Calhoun County has been designated in 18 declarations since 1979, covering 6 disaster types including severe storm (9), flood (4), biological (2).
| Year | Type | Event name |
|---|---|---|
| 2024 | Severe Storm | Severe Storms, Tornadoes, And Flooding |
| 2022 | Severe Storm | Severe Storms, Straight-Line Winds, And Tornadoes |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2019 | Flood | Severe Storms And Flooding |
| 2010 | Severe Storm | Severe Winter Storms And Snowstorm |
| 2010 | Severe Storm | Severe Winter Storm |
| 2010 | Severe Storm | Severe Storms, Flooding, And Tornadoes |
| 2007 | Severe Storm | Severe Winter Storms |
| 2007 | Severe Storm | Severe Storms And Flooding |
Showing the 10 most recent of 18 total declarations since 1979.
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 | 8.5 | 0 | 0 | — |
| Inland Flooding | Very Low | 20.6 | 3 | 0 | $65K |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Very Low | 14.6 | — | — | — |
| Heat Wave | Very Low | 17.7 | 2 | 0 | — |
| Tornado | Relatively Moderate | 73.6 | 9 | 0 | $2.6M |
| Hurricane | Very Low | 14.7 | 0 | 0 | — |
| Hail | Relatively Moderate | 92.8 | 22 | 0 | $5K |
| Strong Wind | Relatively Moderate | 65.2 | 0 | 0 | — |
| Winter Weather | Relatively Moderate | 61.7 | 0 | 0 | — |
| Ice Storm | Relatively Low | 46.6 | — | — | — |
| Cold Wave | Relatively Low | 60.3 | — | — | — |
| Lightning | Very Low | 20.2 | 1 | 0 | $20K |
| Drought | Relatively High | 97.1 | 0 | 0 | — |
| Landslide | Very Low | 20.5 | 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
Calhoun County ranks in the 9th percentile (Very low) 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 | 9th | Very low |
| Socioeconomic status | 4th | Very low |
| Household characteristics | 34th | Low |
| Racial & ethnic minority status | 17th | Very low |
| Housing type & transportation | 26th | Low |
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 | 3rd | Very Low |
| Risk to homes | 3rd | Very Low |
| Buildings in direct exposure zone | 27.7% | — |
NOAA tracked 37 weather events in this county over 2016–2025: 22 in 2016–20 vs 15 in 2021–25 (-32% — frequency decreasing).
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 Calhoun County?
According to the FEMA National Risk Index, the highest-risk hazards in Calhoun County, Iowa are drought, hail, and tornado. The county's overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Has Calhoun County received federal disaster declarations?
Yes. Calhoun County has received 18 federal disaster declarations since 1979, including declarations in 2024. The most common disaster type on record is severe storm (9 declarations).
Has Calhoun County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for Calhoun County include Severe Storms, Tornadoes, And Flooding (2024). See the declarations table above for the full history since 1979.
How does Calhoun County's natural hazard risk compare to nearby counties?
Among neighboring counties, Webster County, IA has the highest overall natural hazard risk (Relatively Low) and Sac County, IA has the lowest (Very Low). Calhoun County is rated Relatively Low overall.
How is Calhoun County's composite disaster risk index calculated?
Calhoun 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. Calhoun County's composite score of 45 means its overall natural hazard risk is higher than 45% of US counties.