Natural hazards · Ontario

Ontario, WI natural hazards

Most of the natural-hazard damage FEMA expects in Ontario comes from inland flooding, and overall the risk is high for a U.S. community. Flood insurance has paid 6 claims here since 1980. 4 federal disasters brought FEMA money into town.

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

Expected damage

How exposed is Ontario?

High

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Ontario to be higher than in 60% of U.S. communities, mostly from inland flooding and cold waves.

Inland flooding42%Cold waves37%Tornadoes6%Landslides6%Everything else10%

By hazard

What Ontario faces

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

Inland flooding

42% of expected damage

Well above average · higher than 78% of U.S. places

Recorded about 3 times a year in the area

Cold waves

37% of expected damage

Below average · higher than 42% of U.S. places

Recorded about 7 times a year in the area

Tornadoes

6% of expected damage

Well above average · higher than 75% of U.S. places

Recorded about once every 17 years in the area

Landslides

6% of expected damage

Well above average · higher than 97% of U.S. places

Lower here

HurricanesHailIce stormsWinter weatherHeat wavesWildfireEarthquakesStrong windLightningDrought

Not a risk here

Coastal floodingAvalanchesTsunamisVolcanic 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 Ontario flood?

Every paid claim on a federal flood insurance policy in Ontario, from FEMA’s records.

6paid claims since 1980

$158Kpaid to owners

1homes flooded more than once

19802026

Homes that flooded again and again

■ FEMA “severe repetitive loss” (0) ■ flooded 2+ times

of homes in flood zones
are insured

of all homes
are insured

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

Insurance rates: Vernon County.

What’s been done with FEMA grants

9flood-prone properties bought out and cleared

1storm safe rooms built

Disasters that hit Ontario

4 federal disasters brought FEMA money here

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

Brought FEMA money into OntarioDeclared for Vernon County only

2018

Severe Storms, Tornadoes, Straight-Line Winds, Flooding, and Landslides

59 households applied for aid $208K aid approved $840K to the Village of Ontario for repairs

2017

Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mud

$4K to the Village of Ontario for repairs

2008

Severe Storms, Tornadoes, and Flooding

55 households applied for aid $118K aid approved $8K to the Village of Ontario for repairs

2007

Severe Storms and Flooding

19 households applied for aid $25K aid approved $909 to the Village of Ontario for repairs

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

Around Ontario

Ontario and the towns around it

Very lowLowModerateHighVery high

Sheldonmostly inland floodingHigh

Ontariomostly inland floodingHigh

Whitestownmostly inland floodingHigh

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