Natural hazards · Cornwall

Cornwall, SD natural hazards

Most of the natural-hazard damage FEMA expects in Cornwall comes from inland flooding, and overall the risk is low for a U.S. community.

FEMA National Risk Index, December 2025 · OpenFEMA claims, aid & declarations

Expected damage

How exposed is Cornwall?

Low

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Cornwall to be higher than in 29% of U.S. communities, mostly from inland flooding and cold waves.

Inland flooding47%Cold waves26%Hail10%Tornadoes9%Everything else8%

By hazard

What Cornwall faces

Each hazard’s share of the damage FEMA expects here, and how that compares with the rest of the country.

Inland flooding

47% of expected damage

Below average · higher than 40% of U.S. places

Recorded about 3 times a year in the area

Cold waves

26% of expected damage

Above average · higher than 69% of U.S. places

Recorded about 12 times a year in the area

Hail

10% of expected damage

Well above average · higher than 76% of U.S. places

Recorded about 4 times a year in the area

Tornadoes

9% of expected damage

Well above average · higher than 88% of U.S. places

Recorded about once every 2 years in the area

Lower here

Ice stormsWinter weatherHeat wavesWildfireEarthquakesLandslidesStrong windLightningDrought

Not a risk here

Coastal floodingHurricanesAvalanchesTsunamisVolcanic activity

Flood risk changes street by street. Check a specific address on FEMA’s flood map, and ask about flood insurance before you buy.

Flood insurance claims

Does Cornwall flood?

FEMA's records show no paid flood insurance claims in Cornwall.

of homes in flood zones
are insured

of all homes
are insured

No community discount. Cornwall isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.

Insurance rates: Spink County.

Disasters that hit Cornwall

Federal disasters declared here

None of the disasters declared for Spink County shows FEMA aid or repair money reaching Cornwall itself in FEMA’s records.

Brought FEMA money into CornwallDeclared for Spink County only

Spink County has had 21 natural disasters declared since 1953, most often floods and severe storms.

Around Cornwall

Cornwall and the towns around it

Very lowLowModerateHighVery high

Pleasant Viewmostly inland floodingModerate

Altoonamostly inland floodingModerate

Belmontmostly inland floodingLow

Cornwallmostly inland floodingLow

Antelopemostly inland floodingLow

Lincolnmostly inland floodingLow

About these numbers

How to read this page

An average, not a forecastFEMA’s National Risk Index estimates the damage 18 kinds of natural hazards cause in a typical year, from decades of records and models. A quiet decade can follow a bad year.

Compared by rate“Higher than N%” compares yearly damage as a share of what’s here, so a big city isn’t rated riskier just for having more buildings. Cornwall is smaller than a census tract, so it shares the figures of the tract around its center.

Money that reached townFlood claims are matched to Cornwall’s own flood-insurance community; household aid to the registrant’s city; repair grants to the Township of Cornwall. FEMA’s model follows property values, so a place that recently lost many homes can rate lower than it feels.

Sources: FEMA National Risk Index (December 2025); OpenFEMA: NFIP redacted claims, multiple-loss properties, community status book and residential penetration rates, housing assistance (owners and renters), public assistance funded projects, hazard mitigation properties and disaster declarations. Census tracts: U.S. Census Bureau.