FEMA Records
1
Total declarations
Pennsylvania · FEMA + NOAA + National Risk Index
Chester County, PA
1 FEMA disaster declarations (2021–2021), with a FEMA National Risk Index rating of Relatively Moderate. Most common hazard: Hurricane.
- 1
- FEMA declarations
- 1
- Major disasters
- 92
- NRI risk · Relatively Moderate
- Hurricane
- Top hazard
The verdict
Chester County ranks in the riskiest 8% of U.S. counties for FEMA-modeled hazard risk, with more federally declared disasters than 0% of the 2,791 counties FEMA tracks. FEMA rates the county's overall risk as Relatively Moderate, based on 1 federal disaster declarations recorded since 2021, most often hurricane, 74% below the national county average of 4.
- Riskiest 8%
- of U.S. counties for FEMA National Risk Index score
- Relatively Moderate
- FEMA National Risk Index rating
- 1
- FEMA declarations vs 4 national county avg
- 1
- hurricane declarations, the most common hazard here
FEMA's National Risk Index score reflects expected annual loss, social vulnerability, and community resilience; the declaration count above reflects only Presidentially declared disasters, not every hazard event.
How does Chester County compare?
Chester County vs. every U.S. county
FEMA disaster declarations, all-time
1 0th percentile higher than 0% of 2,791 counties
Each bar is a band; taller bars hold more counties. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source FEMA Disaster Declarations Summaries v2 · 2026-07-25
Chester County's FEMA Risk Index score
FEMA National Risk Index composite score vs. the Pennsylvania county average
How disaster-prone is Chester County?
Declaration frequency
Chester County, Pennsylvania has recorded 1 FEMA disaster declarations between 2021 and 2021, of which 1 were classified as Major Disaster declarations (DR) requiring federal individual and public assistance. That puts the county's average at - declarations per year, or roughly 0% above the Pennsylvania county average of 1.0 and 74% below the national county average of 3.8. The dominant disaster type on record is Hurricane, with 1 of 1 declarations falling under this category.
FEMA National Risk Index
This county sits among the highest-risk counties nationally on FEMA's National Risk Index, a composite score of 91.9/100 (Relatively Moderate). Expected Annual Loss is rated Relatively Moderate (roughly $172.6M in annualized losses). Social vulnerability reads Very Low and community resilience Very High, both critical modifiers of realized harm here. Of the 18 hazards FEMA models, Drought stands out as the sharpest exposure here, rated Relatively High.
Flood exposure & the bottom line
Taken together, Chester County's federal disaster history is about as quiet as U.S. counties get, a very low relative risk level on this measure.
Risk Assessment
Risk Level
Very Low
vs. Pennsylvania Avg
+0%
State avg: 1.0
vs. National Avg
-74%
National avg: 3.8
Avg Per Year
-
-
FEMA NRI 8-hazard radar - Chester County
How to read this radar
The radar plots Chester County's relative exposure to the eight headline natural hazards used by the FEMA National Risk Index. Each axis is the qualitative NRI risk rating (Very Low through Very High) re-expressed on a 0-100 scale so that the polygon shape lets you compare a county against another at a glance. A rounder polygon means broad multi-hazard exposure; a spiky polygon means one or two dominant hazards drive most of the modeled risk.
NRI Source
FEMA 2023
Latest NRI release
County FIPS
42029
PA state code
Source: FEMA National Risk Index FEMA National Risk Index Per-county per-hazard ratings, 2023 release
Disaster Types
Hurricane 1
Declaration Types
What DR / EM / FM mean
FEMA categorizes declarations as Major Disasters (DR), Emergencies (EM), or Fire Management Assistance (FM).
Major Disaster - 1 100.0%
of all 1 declarations
FEMA Declarations Timeline
| Year | Declarations | |
|---|---|---|
| 2021 | 1 | |
Disaster Declarations
| DR# | Title | Type | Incident | Date |
|---|---|---|---|---|
| 4618 | REMNANTS OF HURRICANE IDA | DR | Hurricane | 2021-09-10 |
Storm Events in Pennsylvania
| Storm Type | Events | Fatalities | Injuries | Property Damage |
|---|---|---|---|---|
| Thunderstorm Wind | 11,662 | 26 | 126 | $124.7M |
| Flash Flood | 2,744 | 23 | 9 | $467.1M |
| Winter Weather | 2,200 | 34 | 318 | $1.0M |
| Hail | 1,636 | 0 | 0 | $5.0M |
| Winter Storm | 1,067 | 14 | 33 | $2.9M |
Source: NOAA Storm Events Database NOAA Storm Events Database State-level aggregated data, 2015–2025
FEMA National Risk Index
Overall Risk
Relatively Moderate
Score: 91.9/100
Expected Annual Loss
Relatively Moderate
$172.6M/year
Social Vulnerability
Very Low
Community Resilience
Very High
Hazard Risk Breakdown
Drought Relatively High
Winter Weather Very High
Heat Wave Relatively Moderate
Strong Wind Relatively High
Lightning Relatively High
Earthquake Relatively Moderate
Hurricane Relatively Moderate
Tornado Relatively Moderate
Ice Storm Relatively High
Cold Wave Relatively Moderate
Landslide Relatively Low
Hail Relatively Low
Wildfire Very Low
Coastal Flooding No Rating
Source: FEMA National Risk Index (NRI) FEMA National Risk Index (NRI) Ratings reflect relative scores among all US counties. Data: hazards.fema.gov/nri
Counties with Similar Risk in Pennsylvania
Disaster Preparedness Guides
Related
Frequently Asked Questions
How many natural disasters has Chester County, Pennsylvania had?
Chester County, Pennsylvania has received 1 FEMA disaster declarations from 2021 to 2021. Of these, 1 were major disaster declarations.
What is the most common disaster type in Chester County?
The most common disaster type in Chester County is Hurricane, with 1 declaration.
How does Chester County's disaster risk compare to the Pennsylvania average?
Chester County has 1 disaster declarations, which is 0% higher than the Pennsylvania county average of 1.0 declarations. Compared to the national county average of 3.8, it is 74% lower.
How many major FEMA disaster declarations has Chester County received?
Chester County has received 1 major disaster declaration, representing 100% of all 1 disaster declarations. Major disaster declarations typically involve significant damage requiring federal assistance.
What types of storms are most common in Pennsylvania?
The most common storm types in Pennsylvania include Thunderstorm Wind (11,662 events), Flash Flood (2,744 events), Winter Weather (2,200 events). NOAA storm event data covers severe weather from 2015 to 2025.
What is the overall disaster risk level for Chester County?
Chester County has just 1 FEMA disaster declaration on record, placing it in the very-low-risk band, among the quieter counties in FEMA's declaration history.
What is the FEMA National Risk Index score for Chester County?
According to the FEMA National Risk Index, Chester County, Pennsylvania has an overall risk score of 91.9 out of 100 (Relatively Moderate). The county's social vulnerability rating is Very Low and community resilience is Very High. The Expected Annual Loss (EAL) score is Relatively Moderate, representing $172.6M in annualized losses.
Which natural hazard poses the greatest risk to Chester County?
Based on FEMA NRI data, the highest-risk natural hazard in Chester County is Drought (risk rating: Relatively High). Other significant hazards include Winter Weather (Very High) and Heat Wave (Relatively Moderate). These scores are based on FEMA's analysis of historical event frequency, exposed assets, and community vulnerability.
Data Sources & Methodology
Disaster declaration data comes from the FEMA OpenFEMA Disaster Declarations Summaries v2 API, which includes all federally declared disasters, emergencies, and fire management assistance grants.
Storm event data is sourced from the NOAA Storm Events Database (2015–2025), which tracks significant weather events including thunderstorms, tornadoes, floods, and winter storms.
This data is provided for informational purposes only. FEMA disaster declarations represent federal response actions and may not capture all local emergencies or weather events.
What this means for Chester County
Chester County, PA runs 0% above the Pennsylvania county average for federal disaster declarations (1 vs 1), a very low historical load overall.
- Its most common federal declaration type is major disaster (1 of 1) - know the hazards most likely here before they happen. Pennsylvania overview
- See how this county ranks against the rest of the country for disaster frequency. Most-disaster rankings
- Read how to read FEMA declarations, NRI risk scores, and what they do and don't tell you. Disaster-data guide
Historical declaration counts describe past federal response, not a forecast. For current threats, follow the National Weather Service and local officials; in an emergency call 911.
According to the Federal Emergency Management Agency, this profile draws on 2,791 tracked U.S. counties in FEMA's Disaster Declarations Summaries dataset, refreshed as of 2026-07-25. Read our methodology - how this data is sourced, computed, and verified.
All federal data sources used on this page
- FEMA OpenFEMA, Disaster Declarations Summaries v2 - all federally-declared disasters for this county. fema.gov/openfema/disaster-declarations
- FEMA National Risk Index (NRI) - per-county per-hazard risk ratings and expected annual loss. hazards.fema.gov/nri
- NOAA NCEI Storm Events Database - state-level storm/severe-weather event records, 2015–2025. ncdc.noaa.gov/stormevents
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainHazard Editorial
Verify with FEMA → · Verify with FEMA NRI → · Verify with NOAA →
Every figure on PlainHazard is rendered directly from FEMA federal disaster data, no number is typed in by an editor. This page draws directly on FEMA federal disaster data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or national statistics report, or report a data error.