Natural disaster risk in Mercer County, Pennsylvania
Pennsylvania · population 110,623 · FIPS 42085
Overall: relatively low risk
Mercer County has a composite risk score of 77.7 out of 100 — higher than 77% of US counties. It ranks 27 of 67 in Pennsylvania (1 = highest risk). Its highest-rated hazards are lightning, inland (riverine) flooding, winter weather.
Drought now: No: no drought or dryness
No. On the U.S. Drought Monitor map valid 13 October 2026, no part of Mercer County is in drought or abnormally dry (none of D0 to D4). That has been so for 28 weeks in a row.
Drought in Mercer County: the last 52 weeks · droughtmonitor.unl.edu
The U.S. Drought Monitor is jointly produced by the National Drought Mitigation Center at the University of Nebraska-Lincoln, the United States Department of Agriculture, the National Oceanic and Atmospheric Administration and the National Aeronautics and Space Administration. Map courtesy of NDMC.
Risk, loss, vulnerability and resilience
| Measure | Rating and score |
|---|---|
| Overall risk Expected annual loss, adjusted for social vulnerability and community resilience. |
Relatively low 77.7 |
| Expected annual loss About $34.1 million a year, on average, across all 18 hazards. |
Relatively low 76 |
| Social vulnerability Higher means people may find it harder to prepare and recover. |
Relatively moderate 54.8 |
| Community resilience Higher means a stronger ability to prepare, adapt and recover. |
Relatively high 75.5 |
Risk by hazard
FEMA's risk rating for each of 18 natural hazards in Mercer County, highest first. "Not applicable" means the hazard is not modelled here.
| Hazard | Risk rating and score |
|---|---|
| Lightning | Relatively high 87 |
| Inland (riverine) flooding | Relatively moderate 87 |
| Winter weather | Relatively moderate 77 |
| Hail | Relatively moderate 75 |
| Strong wind | Relatively moderate 73 |
| Hurricane | Relatively low 64 |
| Tornado | Relatively low 55 |
| Ice storm | Relatively low 42 |
| Earthquake | Very low 51 |
| Landslide | Very low 43 |
| Wildfire | Very low 36 |
| Heat wave | Very low 28 |
| Cold wave | Very low 23 |
| Avalanche | Not applicable |
| Coastal flooding | Not applicable |
| Drought | No rating |
| Tsunami | Not applicable |
| Volcanic activity | Not applicable |
FEMA disaster declarations for Mercer County
Federal declarations that designated Mercer County, since 1 Jan 2024 (the period this site keeps from OpenFEMA). Older declarations are in FEMA's own dataset.
Not since 1 Jan 2024: no FEMA disaster declaration in the records this site read names Mercer County.
All FEMA declarations in Pennsylvania, with estimated apply-by dates · Open FEMA deadlines
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). Dataset: Disaster Declarations Summaries - v2.
How to read these ratings
- Ratings run in five steps: very low, relatively low, relatively moderate, relatively high and very high. They compare a county with every other US county; they are not a measure of danger on their own.
- Scores run from 0 to 100 and are national percentiles. The bar shows the score: a score of 80 means a higher value than 80% of US counties.
- Overall risk combines the expected annual loss with social vulnerability and community resilience.
- Expected annual loss is the average yearly loss to buildings, people and agriculture the model expects from all 18 hazards.
- Social vulnerability describes how hard it may be for people to prepare for and recover from a disaster. Higher is worse.
- Community resilience describes a community's ability to prepare, adapt and recover. Higher is better.
- "Not applicable" means FEMA does not model that hazard there (for example, hurricanes far inland).
About this data
Source: FEMA National Risk Index, version 1.20, released December 2025, published by the Federal Emergency Management Agency (US public domain). About the National Risk Index. The index is a model of relative risk built from historical hazard records, what is exposed and community factors. It is not a forecast, it does not describe any single property, and it is not insurance or financial advice. For decisions about a specific address, check FEMA's flood maps and your local emergency management office.
Questions
What is the natural disaster risk in Mercer County, Pennsylvania?
FEMA's National Risk Index rates the overall risk in Mercer County as relatively low, with a score of 77.7 out of 100 (higher than 77% of US counties). That is a comparison with other US counties, not a forecast.
What are the biggest natural hazards in Mercer County?
The hazards rated highest for Mercer County are lightning (relatively high), inland (riverine) flooding (relatively moderate), winter weather (relatively moderate).
What is the flood risk in Mercer County?
FEMA rates inland (river and rain) flooding risk in Mercer County as relatively moderate. For a specific property, check the FEMA flood map and your local floodplain office.
Has Mercer County had a FEMA disaster declaration?
Not since 1 Jan 2024: no FEMA disaster declaration in the records this site read names Mercer County.
Is Mercer County in a drought?
No. On the U.S. Drought Monitor map valid 13 October 2026, no part of Mercer County is in drought or abnormally dry (none of D0 to D4). That has been so for 28 weeks in a row.
Every county in Pennsylvania, ranked · All states · Disasters near me