Natural hazards · Mercier

Mercier, SD natural hazards

Most of the natural-hazard damage FEMA expects in Mercier 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 Mercier?

Low

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Mercier to be higher than in 37% of U.S. communities, mostly from inland flooding and cold waves.

Inland flooding38%Cold waves33%Hail9%Tornadoes7%Strong wind6%Everything else8%

By hazard

What Mercier faces

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

Inland flooding

38% of expected damage

Below average · higher than 41% of U.S. places

Recorded about 5 times a year in the area

Cold waves

33% of expected damage

Above average · higher than 71% of U.S. places

Recorded about 13 times a year in the area

Hail

9% of expected damage

Well above average · higher than 80% of U.S. places

Recorded about 4 times a year in the area

Tornadoes

7% of expected damage

Well above average · higher than 81% of U.S. places

Recorded about once every 2 years in the area

Strong wind

6% of expected damage

Well above average · higher than 93% of U.S. places

Recorded about 3 times a year in the area

Lower here

Ice stormsWinter weatherHeat wavesWildfireEarthquakesLandslidesLightningDrought

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 Mercier flood?

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

of homes in flood zones
are insured

of all homes
are insured

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

Insurance rates: Brown County.

Disasters that hit Mercier

Federal disasters declared here

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

Brought FEMA money into MercierDeclared for Brown County only

Brown County has had 17 natural disasters declared since 1953, most often floods and severe storms.

Around Mercier

Mercier and the towns around it

Very lowLowModerateHighVery high

Aberdeenmostly cold wavesModerate

Merciermostly inland floodingLow

Raviniamostly inland floodingLow

Highlandmostly inland floodingLow

Cortlandtmostly cold wavesLow

Minamostly cold wavesLow

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