Armstrong County, Pennsylvania: Natural Disaster Risk and History
Armstrong County, Pennsylvania has a Relatively Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 69.3 out of 100, higher than about 69% of US counties, with landslides, inland (river and flash) flooding and lightning scoring highest of its 18 hazards and $28 million a year in expected losses.
OpenFEMA lists 15 federal disaster declarations that included Armstrong County since 1972, not counting 2 for COVID-19; the latest is EM-3356-PA (Hurricane Sandy, declared 29 October 2012). NOAA's Storm Prediction Center recorded 11 tornadoes touching Armstrong County from 1950 to 2025.
Live weather alerts for Pennsylvania All official warnings Latest FEMA declarations
Population 65,530 Buildings worth $14 billion Area 671 sq mi Risk rank in Pennsylvania 33 of 67 FIPS 42005
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Landslide | Relatively Low | 85.3 | $30,887 | about 1.3 a year | — |
| Inland flooding | Relatively Moderate | 85.1 | $26 million | about 1.7 a year | 48 |
| Lightning | Relatively Moderate | 71.6 | $517,064 | about 41 a year | 144,298 strikes |
| Avalanche | Very Low | 52.5 | $686 | about once every 100 years | 0 |
| Hurricane | Very Low | 52.2 | $87,906 | about once every 34 years | 8 |
| Hail | Relatively Low | 36.4 | $153,462 | about 2.7 a year | 101 |
| Earthquake | Very Low | 35.2 | $110,808 | rarer than once in 1,000 years | — |
| Tornado | Relatively Low | 34.2 | $637,226 | about once every 4.2 years | 10 |
| Strong wind | Relatively Low | 30.9 | $294,152 | about 2.4 a year | 90 |
| Heat wave | Very Low | 30.8 | $139,223 | about 1.3 a year | 26 |
| Ice storm | Relatively Low | 27.7 | $27,338 | about once every 3.0 years | 23 |
| Wildfire | Very Low | 22.0 | $8,580 | rarer than once in 1,000 years | — |
| Cold wave | Very Low | 9.4 | $66,659 | about 3.4 a year | 64 |
| Winter weather | Very Low | 4.8 | $3,503 | about 14 a year | 256 |
| Drought | No Rating | 0.0 | — | — | 0 |
| Coastal flooding | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic activity | Not Applicable | — | — | — | — |
Score: FEMA's percentile among US counties that face the hazard (higher = more risk). Expected loss: FEMA's modelled average yearly loss to buildings, people (as a statistical value) and crops. How often: FEMA's annualised frequency of the hazard in the county; for some hazards it counts event-days, so it is a rough guide, not a forecast. "Not Applicable" means FEMA does not model that hazard here.
Federal disaster declarations 15
Most common: Flood 5, Hurricane 3, Snowstorm 3, Severe Storm 3.
| Decade | Declarations | Incident types |
|---|---|---|
| 1970s | 1 | Flood |
| 1980s | 3 | Flood ×2, Tornado |
| 1990s | 5 | Flood ×2, Snowstorm ×2, Severe Storm |
| 2000s | 4 | Severe Storm ×2, Hurricane ×2 |
| 2010s | 2 | Hurricane, Snowstorm |
The last 10
Widest declarations that included Armstrong County
- Hurricane Sandy (2012, EM-3356-PA): 67 Pennsylvania counties designated.
- Hurricane Katrina (2005, EM-3235-PA): 67 Pennsylvania counties designated.
- Tropical Depression Ivan (2004, DR-1557-PA): 67 Pennsylvania counties designated.
Named storms in its declarations: Hurricane Sandy (2012), Hurricane Katrina (2005), Tropical Depression Ivan (2004), Tropical Depression Frances (2004), Tropical Storm Agnes (1972).
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. Pennsylvania also had 5 statewide declarations with no county list.
Tornado record since 1950 11
| Tornadoes touching the county | 11 |
|---|---|
| Strongest-rated | (E)F4 ×1 |
| Peak month | June (4) |
| Deadliest | 3 Jun 1980, F4, 11.8 mi path, 0 killed, 140 injured |
| Longest path | 27 Jun 1951, F2, 19.7 mi path |
| Most recent | 31 Mar 2022, EF2, 8.6 mi path |
| Deaths / injuries on those paths | 0 / 144 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 2 | 4 | 4 | 0 | 1 | 0 | 0 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 1 | 1 | 2 | 3 | 1 | 1 | 1 | 1 |
Deaths and injuries are for each tornado's whole path, which can run beyond this county. F-scale ratings before February 2007, Enhanced Fujita (EF) after.
How Armstrong County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| Armstrong County (this page) | — | Relatively Low | 69.3 | Landslide |
| Indiana County | 36 km | Relatively Low | 63.7 | Landslide |
| Butler County | 39 km | Relatively Low | 79.3 | Lightning |
| Clarion County | 42 km | Very Low | 30.0 | Lightning |
| Jefferson County | 53 km | Relatively Low | 57.9 | Lightning |
| Westmoreland County | 56 km | Relatively Moderate | 87.8 | Lightning |
Nearest by distance between county centres. Every county in Pennsylvania, ranked.
Vulnerability and resilience
| Social vulnerability | Relatively Moderate 42.9 |
|---|---|
| Community resilience | Very High 86.6 |
| Community risk factor | 1.06 |
| Expected annual loss, all hazards | $28 million |
FEMA scales expected losses up where social vulnerability is high (people who may find it harder to prepare, evacuate or recover) and down where community resilience is high. A factor above 1 raises the risk score. For social vulnerability a high rating is worse; for resilience a high rating is better.
Prepare for Armstrong County's main hazards
- Right now: National Weather Service alerts for Pennsylvania · all official warnings on Global Incident Tracker.
- Landslide: Landslides recorded
- Inland flooding: Flood safety: why shallow water kills · Floods recorded
- Lightning: Weather alerts for Pennsylvania
- Your property's flood zone: FEMA Flood Map Service Center ↗ — this page cannot tell you that.
- Official preparedness guidance: Ready.gov ↗ and your county emergency management office.
What this page shows, and what it misses
FEMA's National Risk Index rates a whole county against every other US county; it is a planning-level estimate for nationwide comparison, not a flood-zone map and not a substitute for a local risk assessment or the risk to one home. Declarations are presidential disaster, emergency and fire management declarations that named this county; state declarations and SBA or USDA designations are not included. Tornadoes are counted when the county is one of up to four listed on the track; 670 tornadoes that crossed a state line carry no county list in NOAA's file and are left out.
Federal Emergency Management Agency (FEMA), National Risk Index Dataset: National Risk Index Counties - v1.20.0 (December 2025). Retrieved from https://services.arcgis.com/XG15cJAlne2vxtgt/ArcGIS/rest/services/National_Risk_Index_Counties/FeatureServer/0/query on November 2, 2026, 1:20 PM EST. This product uses the Federal Emergency Management Agency’s National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Federal Emergency Management Agency (FEMA), OpenFEMA Dataset: Disaster Declarations Summaries - v2, retrieved from https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries on November 2, 2026, 1:21 PM EST. This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Tornado records: NOAA/NWS Storm Prediction Center, Severe Weather Database, tornadoes 1950–2025 (https://www.spc.noaa.gov/wcm/data/1950-2025_actual_tornadoes.csv, downloaded 2 November 2026). Public domain; not endorsed by NOAA. Compiled by Global Incident Tracker.
Questions about Armstrong County
What natural disasters is Armstrong County, Pennsylvania most at risk from?
Armstrong County, Pennsylvania has a Relatively Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 69.3 out of 100, higher than about 69% of US counties, with landslides, inland (river and flash) flooding and lightning scoring highest of its 18 hazards and $28 million a year in expected losses.
How many federal disaster declarations has Armstrong County had?
OpenFEMA lists 15 federal disaster declarations that included Armstrong County since 1972, not counting 2 for COVID-19; the latest is EM-3356-PA (Hurricane Sandy, declared 29 October 2012). Another 5 Pennsylvania declarations were made statewide without a county list.
How many tornadoes have hit Armstrong County?
NOAA's Storm Prediction Center recorded 11 tornadoes touching Armstrong County from 1950 to 2025. The deadliest: 3 Jun 1980, F4, 11.8 mi path, 0 killed, 140 injured (deaths and injuries are for the whole path).
Is the National Risk Index a flood zone map?
No. The National Risk Index is a planning-level estimate for a whole county, built for nationwide comparison. It does not tell you the flood zone or the risk of a single property: for that, look up the address on FEMA's Flood Map Service Center (msc.fema.gov) and ask your local floodplain manager.