Santa Cruz County, Arizona Natural Disaster Risk
FEMA National Risk Index assessment · AZ
MediumComposite Risk Score
National percentile: 88th
Santa Cruz County faces medium composite natural disaster risk (NRI Risk Index score 88.3, 88th national percentile), driven primarily by heat wave and wildfire exposure. Expected annual loss across all 18 hazard types is $42M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Santa Cruz County carries a medium composite natural disaster risk, with a National Risk Index score of 88.3 out of 100 — placing it in the 88th national percentile and near the national midpoint for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Risk here concentrates in heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at High risk — $16M in expected annual loss and about 3.96 events per year; wildfire (uncontrolled fires that spread across wildland and into communities) at High risk — $8M in expected annual loss and about 0.01 events per year; and lightning (electrical discharges from storms that ignite fires and cause casualties) at High risk — $631K in expected annual loss and about 57.01 events per year. Across all hazards, FEMA estimates $42M in expected annual loss for a population of 48K.
Beyond physical exposure, Santa Cruz County has a very high social vulnerability rating (how susceptible the population is to harm) and a very 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: Santa Cruz County has received 8 federal disaster declarations since 1977, including 3 for flood events and 2 for biological events. The most recent was Covid-19 Pandemic (biological), declared in April 2020.
Among 15 Arizona counties, Santa Cruz County ranks #10 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Heat Wave | High | 3.96 / yr | $16M |
| Wildfire | High | 0.01 / yr | $8M |
| Lightning | High | 57.01 / yr | $631K |
| Riverine Flood | Medium | 2.75 / yr | $18M |
| Landslide | Low | 1.05 / yr | $3K |
| Drought | Low | 55.56 / yr | $117K |
| Earthquake | Very Low | 0.00 / yr | $110K |
| Avalanche | Very Low | 0.01 / yr | $67 |
| Strong Wind | Low | 0.90 / yr | $163K |
| Winter Weather | Very Low | 3.66 / yr | $10K |
| Hurricane | Very Low | 0.05 / yr | $3K |
| Hail | Very Low | 0.37 / yr | $18K |
| Tornado | Very Low | 0.04 / yr | $30K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Cold Wave | Very Low | 0.00 / yr | $0 |
| Ice Storm | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Santa Cruz County has received 8 federal disaster declarations since 1977, most recently Covid-19 Pandemic in April 2020. Most frequent causes: Flood (3), Biological (2), Hurricane (1).
| Declared | Type | Disaster |
|---|---|---|
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| April 2002 | Fire | Az-Ryan-Wildfire-4/30/2002 |
| October 2000 | Severe Storm | Severe Storms and Flooding |
| January 1993 | Flood | Severe Storms, Tornadoes & Flooding |
| October 1983 | Flood | Severe Storms & Flooding |
| November 1977 | Flood | Severe Storms & Flooding |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Santa Cruz County?
Santa Cruz County has a composite FEMA National Risk Index score of 88.3 out of 100, placing it in the Medium category and the 88th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Santa Cruz County?
The three highest-rated hazards are Heat Wave (High, $16M EAL), Wildfire (High, $8M EAL), Lightning (High, $631K EAL). These account for most of the county's expected annual losses.
How does Santa Cruz County compare to other Arizona counties?
Santa Cruz County ranks #10 of 15 Arizona counties for overall natural disaster risk, with a medium rating.
How many federally declared disasters has Santa Cruz County had?
FEMA records 8 federal disaster declarations for Santa Cruz County since 1977, most often 3 for flood events and 2 for biological 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. Santa Cruz County's $42M EAL is a statistical average, not a guarantee for any specific year or address.