Allegheny County, PA
FEMA National Risk Index scores, disaster declarations & hazard data
Allegheny County has experienced 18 federally declared disasters since 1972, most recently Covid-19 in 2020. Its overall natural hazard risk is rated Relatively High — higher risk than most US counties.
Allegheny County's highest-rated hazards are inland flooding, cold wave, and strong wind, with its top risk rated "Very High" by FEMA's National Risk Index. NOAA records 487 storm events in the county over the past decade.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Allegheny County has been designated in 18 declarations since 1972, covering 6 disaster types including flood (5), severe storm (4), hurricane (3).
| Year | Type | Event name |
|---|---|---|
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2014 | Severe Storm | Severe Storms, Tornadoes, And Flooding |
| 2013 | Hurricane | Hurricane Sandy |
| 2010 | Snowstorm | Severe Winter Storms And Snowstorms |
| 2005 | Hurricane | Hurricane Katrina |
| 2004 | Hurricane | Tropical Depression Ivan |
| 2004 | Severe Storm | Severe Storms And Flooding Associated With Tropical Depression Frances |
| 1998 | Severe Storm | Severe Storms, Tornadoes,And Flooding |
| 1996 | Flood | Severe Storms And Flooding |
Showing the 10 most recent of 18 total declarations since 1972.
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Very Low | 60.4 | 0 | 0 | — |
| Inland Flooding | Very High | 99.2 | 328 | 0 | $14.9M |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively Low | 87.9 | — | — | — |
| Heat Wave | Relatively Moderate | 94.3 | 1 | 1 | — |
| Tornado | Relatively High | 91.2 | 12 | 0 | $2.0M |
| Hurricane | Relatively Low | 75.9 | 0 | 0 | — |
| Hail | Very Low | 31.3 | 143 | 0 | — |
| Strong Wind | Relatively High | 96.3 | 0 | 0 | — |
| Winter Weather | Relatively High | 93.3 | 0 | 0 | — |
| Ice Storm | Very High | 96.1 | — | — | — |
| Cold Wave | Very High | 98.8 | — | — | — |
| Lightning | Relatively High | 93.7 | 3 | 0 | $60K |
| Drought | No Rating | 0 | 0 | 0 | — |
| Landslide | Relatively Low | 87.2 | 1 | 0 | — |
| Avalanche | Very Low | 28.1 | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic Activity | Not Applicable | — | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
Allegheny County ranks in the 31st percentile (Low) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 31st | Low |
| Socioeconomic status | 20th | Very low |
| Household characteristics | 22nd | Very low |
| Racial & ethnic minority status | 58th | Moderate |
| Housing type & transportation | 60th | Moderate |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 20th | Relatively Low |
| Risk to homes | 20th | Relatively Low |
| Buildings in direct exposure zone | 21.6% | — |
NOAA tracked 487 weather events in this county over 2016–2025: 245 in 2016–20 vs 242 in 2021–25 (-1% — relatively stable).
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in Allegheny County?
According to the FEMA National Risk Index, the highest-risk hazards in Allegheny County, Pennsylvania are inland flooding, cold wave, and strong wind. The county's overall natural hazard risk is rated Relatively High — higher risk than most US counties.
Has Allegheny County received federal disaster declarations?
Yes. Allegheny County has received 18 federal disaster declarations since 1972, including declarations in 2020. The most common disaster type on record is flood (5 declarations).
Has Allegheny County had any FEMA disaster declarations in 2024, 2025, or 2026?
No federal disaster declarations have been recorded for Allegheny County since the start of 2024. Its most recent declaration on record is Covid-19 in 2020.
How does Allegheny County's natural hazard risk compare to nearby counties?
Among neighboring counties, Westmoreland County, PA has the highest overall natural hazard risk (Relatively Moderate) and Hancock County, WV has the lowest (Very Low). Allegheny County is rated Relatively High overall.
How is Allegheny County's composite disaster risk index calculated?
Allegheny County's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. Allegheny County's composite score of 98 means its overall natural hazard risk is higher than 98% of US counties.