Dauphin County, Pennsylvania Natural Disaster Risk

FEMA National Risk Index assessment · PA

Medium

Composite Risk Score

91.1

National percentile: 91th

Dauphin County faces medium composite natural disaster risk (NRI Risk Index score 91.1, 91th national percentile), driven primarily by winter weather and riverine flood exposure. Expected annual loss across all 18 hazard types is $100M.

Source: FEMA National Risk Index v1.20 · Updated December 2025

Risk Overview

FEMA's National Risk Index rates Dauphin County at medium composite risk, with a National Risk Index score of 91.1 out of 100 — placing it in the 91st national percentile and near the national midpoint for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.

The county's risk is driven primarily by winter weather (heavy snow, blizzards, and hazardous winter conditions) at Very High risk — $1M in expected annual loss and about 12.32 events per year; riverine flood (rivers and streams overflowing their banks after heavy rain or snowmelt) at High risk — $75M in expected annual loss and about 2.04 events per year; and strong wind (damaging straight-line winds outside of tornadoes and hurricanes) at High risk — $3M in expected annual loss and about 4.75 events per year. Across all hazards, FEMA estimates $100M in expected annual loss for a population of 286K.

Beyond physical exposure, Dauphin County has a low 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 federal record bears this out: Dauphin County has received 22 federal disaster declarations since 1972, including 7 for flood events and 5 for hurricane events. The most recent was Remnants of Hurricane Ida (hurricane), declared in September 2021.

Among 67 Pennsylvania counties, Dauphin County ranks #11 for overall natural disaster risk.

Expected Annual Loss $100M Annualized county-level EAL
Social Vulnerability Low Population sensitivity
Community Resilience Very High Capacity to recover
Population 286K Latest estimate

Top Hazards

Very High $1M/yr
High $75M/yr
High $3M/yr

All 18 Hazard Risks

Winter Weather Very High 12.32 / yr$1M
Riverine Flood High 2.04 / yr$75M
Strong Wind High 4.75 / yr$3M
Hurricane Medium 0.07 / yr$7M
Heat Wave Medium 5.05 / yr$3M
Lightning High 35.24 / yr$1M
Earthquake Low 0.00 / yr$4M
Landslide Low 0.59 / yr$29K
Tornado Medium 0.28 / yr$4M
Cold Wave Medium 1.21 / yr$2M
Ice Storm Low 0.58 / yr$94K
Drought Low 0.37 / yr$141K
Avalanche Very Low 0.01 / yr$287
Wildfire Very Low 0.00 / yr$25K
Hail Very Low 2.22 / yr$89K
Coastal Flood Very Low 0.00 / yr$0
Tsunami Very Low 0.00 / yr$0
Volcanic Activity Very Low 0.00 / yr$0

Disaster History

Dauphin County has received 22 federal disaster declarations since 1972, most recently Remnants of Hurricane Ida in September 2021. Most frequent causes: Flood (7), Hurricane (5), Snowstorm (4).

DeclaredTypeDisaster
September 2021HurricaneRemnants of Hurricane Ida
March 2020BiologicalCovid-19 Pandemic
March 2020BiologicalCovid-19
March 2016SnowstormSevere Winter Storm and Snowstorm
January 2013HurricaneHurricane Sandy
October 2012HurricaneHurricane Sandy
September 2011FloodTropical Storm Lee
September 2011FloodRemnants of Tropical Storm Lee
April 2010SnowstormSevere Winter Storms and Snowstorms
June 2006Severe StormSevere Storms, Flooding, and Mudslides

Showing the 10 most recent of 22 declarations.

Source: FEMA Disaster Declarations Summaries (OpenFEMA).

Frequently Asked Questions

What is the overall natural disaster risk for Dauphin County?

Dauphin County has a composite FEMA National Risk Index score of 91.1 out of 100, placing it in the Medium category and the 91th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.

What are the top natural hazards in Dauphin County?

The three highest-rated hazards are Winter Weather (Very High, $1M EAL), Riverine Flood (High, $75M EAL), Strong Wind (High, $3M EAL). These account for most of the county's expected annual losses.

How does Dauphin County compare to other Pennsylvania counties?

Dauphin County ranks #11 of 67 Pennsylvania counties for overall natural disaster risk, with a medium rating.

How many federally declared disasters has Dauphin County had?

FEMA records 22 federal disaster declarations for Dauphin County since 1972, most often 7 for flood events and 5 for hurricane events. The most recent was Remnants of Hurricane Ida, declared in September 2021.

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. Dauphin County's $100M EAL is a statistical average, not a guarantee for any specific year or address.