Day County, SD: Tornado Risk and Shelter Cost
Day County's tornado history, by the numbers
NOAA's Storm Prediction Center has recorded 33 tornado tracks touching Day County since 1953 - about one every 2.3 years on average. That puts it in our Elevated band nationally. Against the rest of the country, that is the 72nd percentile for frequency. South Dakota has 66 counties in this dataset; Day County ranks 23 of them by frequency.
Has Day County ever had a violent tornado?
Nothing violent in Day County's file: 33 tracks total, topping out at significant (EF2-3) strength on 2 of them, zero at EF4-5.
Paying for it, if Day County's history says you should
A storm shelter or in-residence safe room typically runs $2,890-$13,280 nationally, around $7,645 for a common single-family installation. No state-administered rebate program specific to South Dakota was confirmed for this site - FEMA's own Hazard Mitigation Assistance grants fund 75% of an approved safe room nationwide, but only some states currently run a homeowner-facing application on top of that.
The gap a shelter does not cover
5,408 people live in Day County, and a tornado outbreak's power loss usually reaches far more of South Dakota than the tracks themselves touch. A portable battery unit is the faster, no-fuel way to bridge that outage.
County-level, not address-level
Treat this as a county-wide figure, not a prediction for one address. Day County covers about 1,028 square miles, so a single touch here counts the same as a single touch in a county a fraction of that size. And records from before the 1990s, NOAA notes, undercount weaker tornadoes in areas with less storm-spotting coverage at the time. Day County has about 5,408 residents.