Natural hazards · Jefferson

Jefferson, SD natural hazards

Most of the natural-hazard damage FEMA expects in Jefferson comes from inland flooding, and overall the risk is very high for a U.S. community. 4 federal disasters brought FEMA money into town.

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

Expected damage

How exposed is Jefferson?

Very high

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Jefferson to be higher than in 82% of U.S. communities, mostly from inland flooding and tornadoes.

Inland flooding58%Tornadoes20%Everything else22%

By hazard

What Jefferson faces

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

Inland flooding

58% of expected damage

Well above average · higher than 90% of U.S. places

Recorded about 4 times a year in the area

Tornadoes

20% of expected damage

Well above average · among the top 1% of U.S. places

Recorded about once every 15 years in the area

Lower here

HailIce stormsWinter weatherCold wavesHeat 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 Jefferson flood?

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

of homes in flood zones
are insured

of all homes
are insured

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

Insurance rates: Union County.

Disasters that hit Jefferson

4 federal disasters brought FEMA money here

Disasters the President declared that paid out in Jefferson itself: aid to households, or repair grants to the City of Jefferson.

Brought FEMA money into JeffersonDeclared for Union County only

2024

Severe Storms, Straight-Line Winds, and Flooding

66 households applied for aid $1.3M aid approved

2019

Severe Winter Storm, Snowstorm, and Flooding

$12K to the City of Jefferson for repairs

2014

Severe Storms, Tornadoes, and Flooding

$8K to the City of Jefferson for repairs

2011

Flooding

126 households applied for aid $201K aid approved

Union County has had 15 natural disasters declared since 1953, most often floods and severe storms.

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. Jefferson 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 Jefferson’s own flood-insurance community; household aid to the registrant’s city; repair grants to the City of Jefferson. 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.