Yankton County Disaster Risk

Yankton County has a FEMA National Risk Index rating of Relatively Low, placing it in the 63th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.

Yankton County is evaluated for five major natural hazard types: tornado (87th percentile), wildfire (76th percentile), flooding (57th percentile), earthquake (29th percentile). The highest-risk hazard is tornado at the 87th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.

Yankton County's composite risk percentile is 63th, compared to the South Dakota state average of 27th percentile. The state's overall risk rating is Very Low. This means Yankton County faces higher natural disaster risk than the typical county in South Dakota.

Yes, Yankton County's tornado risk is at the 87th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Yankton County is at the 57th percentile.

FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.

Yankton County's composite risk score of 63th percentile is above the South Dakota state average of 27th percentile. This elevated risk is driven by tornado exposure (87th percentile), along with wildfire and flooding risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.