Armstrong County, Pennsylvania Natural Disaster Risk
FEMA National Risk Index assessment · PA
LowComposite Risk Score
National percentile: 69th
Armstrong County faces low composite natural disaster risk (NRI Risk Index score 69.3, 69th national percentile), driven primarily by landslide and riverine flood exposure. Expected annual loss across all 18 hazard types is $28M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Armstrong County is low, with a National Risk Index score of 69.3 out of 100 — placing it in the 69th 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.
Risk here concentrates in landslide (downhill movement of rock, soil, and debris on unstable slopes) at Low risk — $31K in expected annual loss and about 1.25 events per year; riverine flood (rivers and streams overflowing their banks after heavy rain or snowmelt) at Medium risk — $26M in expected annual loss and about 1.71 events per year; and lightning (electrical discharges from storms that ignite fires and cause casualties) at Medium risk — $517K in expected annual loss and about 40.54 events per year. Across all hazards, FEMA estimates $28M in expected annual loss for a population of 66K.
Beyond physical exposure, Armstrong County has a medium 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 county's disaster history tells the same story: Armstrong County has received 17 federal disaster declarations since 1972, including 5 for flood events and 3 for hurricane events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 67 Pennsylvania counties, Armstrong County ranks #33 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Landslide | Low | 1.25 / yr | $31K |
| Riverine Flood | Medium | 1.71 / yr | $26M |
| Lightning | Medium | 40.54 / yr | $517K |
| Avalanche | Very Low | 0.01 / yr | $686 |
| Hurricane | Very Low | 0.03 / yr | $88K |
| Hail | Low | 2.65 / yr | $153K |
| Earthquake | Very Low | 0.00 / yr | $111K |
| Tornado | Low | 0.24 / yr | $637K |
| Strong Wind | Low | 2.36 / yr | $294K |
| Heat Wave | Very Low | 1.32 / yr | $139K |
| Ice Storm | Low | 0.33 / yr | $27K |
| Wildfire | Very Low | 0.00 / yr | $9K |
| Cold Wave | Very Low | 3.37 / yr | $67K |
| Winter Weather | Very Low | 13.47 / yr | $4K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Drought | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Armstrong County has received 17 federal disaster declarations since 1972, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Flood (5), Hurricane (3), Snowstorm (3).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| October 2012 | Hurricane | Hurricane Sandy |
| April 2010 | Snowstorm | Severe Winter Storms and Snowstorms |
| June 2006 | Severe Storm | Severe Storms, Flooding, and Mudslides |
| September 2005 | Hurricane | Hurricane Katrina |
| September 2004 | Hurricane | Tropical Depression Ivan |
| September 2004 | Severe Storm | Severe Storms and Flooding Associated with Tropical Depression Frances |
| July 1996 | Flood | Severe Storms, Flooding, and Tornadoes |
| January 1996 | Flood | Severe Storms and Flooding |
Showing the 10 most recent of 17 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Armstrong County?
Armstrong County has a composite FEMA National Risk Index score of 69.3 out of 100, placing it in the Low category and the 69th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Armstrong County?
The three highest-rated hazards are Landslide (Low, $31K EAL), Riverine Flood (Medium, $26M EAL), Lightning (Medium, $517K EAL). These account for most of the county's expected annual losses.
How does Armstrong County compare to other Pennsylvania counties?
Armstrong County ranks #33 of 67 Pennsylvania counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Armstrong County had?
FEMA records 17 federal disaster declarations for Armstrong County since 1972, most often 5 for flood events and 3 for hurricane events. The most recent was Covid-19 Pandemic, declared in March 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. Armstrong County's $28M EAL is a statistical average, not a guarantee for any specific year or address.