Polk County, IA
FEMA National Risk Index scores, disaster declarations & hazard data
Polk County has experienced 20 federally declared disasters since 1965, most recently Severe Storms And Tornadoes in 2024. Its overall natural hazard risk is rated Relatively Moderate — near the middle compared to other US counties.
Polk County's highest-rated hazards are strong wind, tornado, and hail, with its top risk rated "Very High" by FEMA's National Risk Index. Recorded storm events have decreased 27% over the past five years compared to the prior five-year period.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Polk County has been designated in 20 declarations since 1965, covering 6 disaster types including flood (8), severe storm (7), biological (2).
| Year | Type | Event name |
|---|---|---|
| 2024 | Severe Storm | Severe Storms, Tornadoes, And Flooding |
| 2024 | Tornado | Severe Storms And Tornadoes |
| 2020 | Severe Storm | Severe Storms |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2019 | Flood | Severe Storms And Flooding |
| 2018 | Severe Storm | Severe Storms, Tornadoes, Straight-Line Winds, And Flooding |
| 2010 | Severe Storm | Severe Storms, Flooding, And Tornadoes |
| 2008 | Severe Storm | Severe Storms, Tornadoes, And Flooding |
| 2007 | Severe Storm | Severe Winter Storms |
Showing the 10 most recent of 20 total declarations since 1965.
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 | 57.7 | 0 | 0 | — |
| Inland Flooding | Relatively Moderate | 92.1 | 79 | 1 | $9.4M |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively Low | 66.8 | — | — | — |
| Heat Wave | Relatively High | 96.7 | 3 | 1 | — |
| Tornado | Relatively High | 98.1 | 16 | 0 | $82.7M |
| Hurricane | Very Low | 27.5 | 0 | 0 | — |
| Hail | Relatively High | 97.9 | 162 | 0 | $612K |
| Strong Wind | Very High | 99.2 | 0 | 0 | — |
| Winter Weather | Relatively High | 90.3 | 0 | 0 | — |
| Ice Storm | Relatively High | 91.7 | — | — | — |
| Cold Wave | Relatively High | 91.3 | — | — | — |
| Lightning | Relatively Moderate | 78.1 | 12 | 0 | $594K |
| Drought | Relatively High | 94.8 | 0 | 0 | — |
| Landslide | Relatively Low | 68.4 | 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
Polk County ranks in the 45th percentile (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 | 45th | Low |
| Socioeconomic status | 24th | Very low |
| Household characteristics | 59th | Moderate |
| Racial & ethnic minority status | 60th | Moderate |
| Housing type & transportation | 60th | 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 | 28th | Relatively Low |
| Risk to homes | 28th | Relatively Low |
| Buildings in direct exposure zone | 18.0% | — |
NOAA tracked 272 weather events in this county over 2016–2025: 157 in 2016–20 vs 115 in 2021–25 (-27% — 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 Polk County?
According to the FEMA National Risk Index, the highest-risk hazards in Polk County, Iowa are strong wind, tornado, and hail. The county's overall natural hazard risk is rated Relatively Moderate — near the middle compared to other US counties.
Has Polk County received federal disaster declarations?
Yes. Polk County has received 20 federal disaster declarations since 1965, including declarations in 2024. The most common disaster type on record is flood (8 declarations).
Has Polk County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for Polk County include Severe Storms, Tornadoes, And Flooding (2024), Severe Storms And Tornadoes (2024). See the declarations table above for the full history since 1965.
How does Polk County's natural hazard risk compare to nearby counties?
Among neighboring counties, Story County, IA has the highest overall natural hazard risk (Relatively Low) and Boone County, IA has the lowest (Very Low). Polk County is rated Relatively Moderate overall.
How is Polk County's composite disaster risk index calculated?
Polk 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. Polk County's composite score of 92 means its overall natural hazard risk is higher than 92% of US counties.