Pennington County, South Dakota Natural Disaster Risk

FEMA National Risk Index assessment · SD

Low

Composite Risk Score

78.6

National percentile: 79th

Pennington County faces low composite natural disaster risk (NRI Risk Index score 78.6, 79th national percentile), driven primarily by wildfire and hail exposure. Expected annual loss across all 18 hazard types is $41M.

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

Risk Overview

Overall natural disaster risk in Pennington County is low, with a National Risk Index score of 78.6 out of 100 — placing it in the 79th national percentile and below the national average 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 wildfire (uncontrolled fires that spread across wildland and into communities) at Medium risk — $8M in expected annual loss and about 0.00 events per year; hail (ice stones from severe thunderstorms that damage property and crops) at High risk — $4M in expected annual loss and about 5.77 events per year; and winter weather (heavy snow, blizzards, and hazardous winter conditions) at High risk — $657K in expected annual loss and about 17.22 events per year. Across all hazards, FEMA estimates $41M in expected annual loss for a population of 109K.

Beyond physical exposure, Pennington County has a low social vulnerability rating (how susceptible the population is to harm) and a 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: Pennington County has received 21 federal disaster declarations since 1965, including 6 for flood events and 5 for fire events. The most recent was Straight-Line Winds (straight-line winds), declared in April 2026.

Among 66 South Dakota counties, Pennington County ranks #3 for overall natural disaster risk.

Expected Annual Loss $41M Annualized county-level EAL
Social Vulnerability Low Population sensitivity
Community Resilience High Capacity to recover
Population 109K Latest estimate

Top Hazards

Medium $8M/yr
High $4M/yr
High $657K/yr

All 18 Hazard Risks

Wildfire Medium 0.00 / yr$8M
Hail High 5.77 / yr$4M
Winter Weather High 17.22 / yr$657K
Lightning High 39.90 / yr$1M
Cold Wave Medium 4.96 / yr$5M
Landslide Low 1.73 / yr$30K
Ice Storm High 0.12 / yr$525K
Riverine Flood Medium 2.07 / yr$17M
Tornado Low 0.58 / yr$2M
Heat Wave Low 0.89 / yr$588K
Earthquake Very Low 0.00 / yr$406K
Strong Wind Low 2.92 / yr$306K
Drought Very Low 53.32 / yr$14K
Avalanche Very Low 0.01 / yr$3
Coastal Flood Very Low 0.00 / yr$0
Hurricane Very Low 0.00 / yr$0
Tsunami Very Low 0.00 / yr$0
Volcanic Activity Very Low 0.00 / yr$0

Disaster History

Pennington County has received 21 federal disaster declarations since 1965, most recently Straight-Line Winds in April 2026. Most frequent causes: Flood (6), Fire (5), Severe Storm (5).

DeclaredTypeDisaster
April 2026Straight-Line WindsStraight-Line Winds
October 2021FireAuburn Fire
March 2021FireSchroeder Fire
April 2020BiologicalCovid-19 Pandemic
March 2020BiologicalCovid-19
September 2019FloodSevere Storms and Flooding
June 2019FloodSevere Winter Storm, Snowstorm, and Flooding
February 2017Severe StormSevere Winter Storm
November 2013Severe StormSevere Winter Storm, Snowstorm, and Flooding
September 2005Coastal StormHurricane Katrina Evacuation

Showing the 10 most recent of 21 declarations.

Source: FEMA Disaster Declarations Summaries (OpenFEMA).

Frequently Asked Questions

What is the overall natural disaster risk for Pennington County?

Pennington County has a composite FEMA National Risk Index score of 78.6 out of 100, placing it in the Low category and the 79th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.

What are the top natural hazards in Pennington County?

The three highest-rated hazards are Wildfire (Medium, $8M EAL), Hail (High, $4M EAL), Winter Weather (High, $657K EAL). These account for most of the county's expected annual losses.

How does Pennington County compare to other South Dakota counties?

Pennington County ranks #3 of 66 South Dakota counties for overall natural disaster risk, with a low rating.

How many federally declared disasters has Pennington County had?

FEMA records 21 federal disaster declarations for Pennington County since 1965, most often 6 for flood events and 5 for fire events. The most recent was Straight-Line Winds, declared in April 2026.

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. Pennington County's $41M EAL is a statistical average, not a guarantee for any specific year or address.