Palo Alto County, Iowa Natural Disaster Risk
FEMA National Risk Index assessment · IA
Very LowComposite Risk Score
National percentile: 15th
Palo Alto County faces very low composite natural disaster risk (NRI Risk Index score 15.5, 15th national percentile), driven primarily by drought and hail exposure. Expected annual loss across all 18 hazard types is $10M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Palo Alto County at very low composite risk, with a National Risk Index score of 15.5 out of 100 — placing it in the 15th national percentile and among the lowest-risk counties in the country. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Most of Palo Alto County's expected losses come from drought (extended dry periods that stress water supplies and agriculture) at Medium risk — $2M in expected annual loss and about 16.30 events per year; hail (ice stones from severe thunderstorms that damage property and crops) at Medium risk — $1M in expected annual loss and about 4.85 events per year; and cold wave (prolonged spells of dangerously low temperatures) at Low risk — $2M in expected annual loss and about 11.37 events per year. Across all hazards, FEMA estimates $10M in expected annual loss for a population of 9K.
Beyond physical exposure, Palo Alto County has a very low social vulnerability rating (how susceptible the population is to harm) and a very high community resilience rating (its capacity to prepare for and recover from disasters). A less vulnerable population paired with strong resilience helps the community absorb and recover from events.
The federal record bears this out: Palo Alto County has received 23 federal disaster declarations since 1965, including 11 for severe storm events and 7 for flood events. The most recent was Severe Storms, Flooding, Straight-Line Winds, and Tornadoes (severe storm), declared in June 2024.
Among 99 Iowa counties, Palo Alto County ranks #93 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Drought | Medium | 16.30 / yr | $2M |
| Hail | Medium | 4.85 / yr | $1M |
| Cold Wave | Low | 11.37 / yr | $2M |
| Lightning | Medium | 40.80 / yr | $512K |
| Winter Weather | Low | 18.21 / yr | $102K |
| Tornado | Low | 0.46 / yr | $1M |
| Ice Storm | Very Low | 0.76 / yr | $38K |
| Strong Wind | Low | 3.68 / yr | $334K |
| Landslide | Very Low | 0.06 / yr | $117 |
| Wildfire | Very Low | 0.00 / yr | $6K |
| Heat Wave | Very Low | 3.95 / yr | $29K |
| Riverine Flood | Very Low | 1.86 / yr | $2M |
| Earthquake | Very Low | 0.00 / yr | $10K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Palo Alto County has received 23 federal disaster declarations since 1965, most recently Severe Storms, Flooding, Straight-Line Winds, and Tornadoes in June 2024. Most frequent causes: Severe Storm (11), Flood (7), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| June 2024 | Severe Storm | Severe Storms, Flooding, Straight-Line Winds, and Tornadoes |
| February 2022 | Severe Storm | Severe Storms, Straight-Line Winds, and Tornadoes |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| March 2019 | Flood | Severe Storms and Flooding |
| August 2018 | Severe Storm | Severe Storms, Tornadoes, Straight-Line Winds, and Flooding |
| July 2014 | Flood | Severe Storms, Tornadoes, Straight-Line Winds, and Flooding |
| July 2013 | Severe Storm | Severe Storms, Tornadoes, and Flooding |
| July 2010 | Severe Storm | Severe Storms, Flooding, and Tornadoes |
| March 2010 | Severe Storm | Severe Winter Storm |
Showing the 10 most recent of 23 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Palo Alto County?
Palo Alto County has a composite FEMA National Risk Index score of 15.5 out of 100, placing it in the Very Low category and the 15th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Palo Alto County?
The three highest-rated hazards are Drought (Medium, $2M EAL), Hail (Medium, $1M EAL), Cold Wave (Low, $2M EAL). These account for most of the county's expected annual losses.
How does Palo Alto County compare to other Iowa counties?
Palo Alto County ranks #93 of 99 Iowa counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Palo Alto County had?
FEMA records 23 federal disaster declarations for Palo Alto County since 1965, most often 11 for severe storm events and 7 for flood events. The most recent was Severe Storms, Flooding, Straight-Line Winds, and Tornadoes, declared in June 2024.
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. Palo Alto County's $10M EAL is a statistical average, not a guarantee for any specific year or address.