Madison County, Idaho Natural Disaster Risk
FEMA National Risk Index assessment · ID
LowComposite Risk Score
National percentile: 59th
Madison County faces low composite natural disaster risk (NRI Risk Index score 58.6, 59th national percentile), driven primarily by lightning and earthquake exposure. Expected annual loss across all 18 hazard types is $22M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Madison County carries a low composite natural disaster risk, with a National Risk Index score of 58.6 out of 100 — placing it in the 59th 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 Madison County's expected losses come from lightning (electrical discharges from storms that ignite fires and cause casualties) at High risk — $1M in expected annual loss and about 36.45 events per year; earthquake (ground shaking from sudden movement along geologic faults) at Low risk — $4M in expected annual loss and about 0.01 events per year; and cold wave (prolonged spells of dangerously low temperatures) at Medium risk — $6M in expected annual loss and about 2.12 events per year. Across all hazards, FEMA estimates $22M in expected annual loss for a population of 53K.
Beyond physical exposure, Madison County has a low social vulnerability rating (how susceptible the population is to harm) and a medium community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
The county's disaster history tells the same story: Madison County has received 5 federal disaster declarations since 1976, including 2 for biological events and 1 for hurricane events. The most recent was Covid-19 Pandemic (biological), declared in April 2020.
Among 44 Idaho counties, Madison County ranks #11 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Lightning | High | 36.45 / yr | $1M |
| Earthquake | Low | 0.01 / yr | $4M |
| Cold Wave | Medium | 2.12 / yr | $6M |
| Heat Wave | Low | 1.24 / yr | $1M |
| Avalanche | Low | 0.03 / yr | $11K |
| Wildfire | Low | 0.00 / yr | $194K |
| Winter Weather | Medium | 21.27 / yr | $134K |
| Volcanic Activity | Very Low | 0.00 / yr | $63 |
| Landslide | Low | 0.26 / yr | $4K |
| Riverine Flood | Low | 0.64 / yr | $9M |
| Hail | Low | 0.33 / yr | $210K |
| Drought | Very Low | 39.51 / yr | $6K |
| Strong Wind | Low | 0.69 / yr | $187K |
| Ice Storm | Very Low | 0.01 / yr | $13K |
| Tornado | Very Low | 0.04 / yr | $70K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Madison County has received 5 federal disaster declarations since 1976, most recently Covid-19 Pandemic in April 2020. Most frequent causes: Biological (2), Hurricane (1), Severe Storm (1).
| Declared | Type | Disaster |
|---|---|---|
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2005 | Hurricane | Hurricane Katrina |
| June 1997 | Severe Storm | Severe Storms, Snowmelt, Land/Mud Slides, Flooding |
| June 1976 | Flood | Dam Collapse, Flooding |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Madison County?
Madison County has a composite FEMA National Risk Index score of 58.6 out of 100, placing it in the Low category and the 59th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Madison County?
The three highest-rated hazards are Lightning (High, $1M EAL), Earthquake (Low, $4M EAL), Cold Wave (Medium, $6M EAL). These account for most of the county's expected annual losses.
How does Madison County compare to other Idaho counties?
Madison County ranks #11 of 44 Idaho counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Madison County had?
FEMA records 5 federal disaster declarations for Madison County since 1976, most often 2 for biological events and 1 for hurricane events. The most recent was Covid-19 Pandemic, declared in April 2020.
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. Madison County's $22M EAL is a statistical average, not a guarantee for any specific year or address.