Natural hazards · Onalaska

Onalaska, WI natural hazards

Most of the natural-hazard damage FEMA expects in Onalaska comes from cold waves, and overall the risk is very low for a U.S. community. Flood insurance has paid 2 claims here since 1980. 6 federal disasters brought FEMA money into town.

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

Expected damage

How exposed is Onalaska?

Very low

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Onalaska to be higher than in 15% of U.S. communities, mostly from cold waves and inland flooding.

Cold waves38%Inland flooding29%Tornadoes14%Hail8%Heat waves7%Everything else4%

By hazard

What Onalaska faces

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

Cold waves

38% of expected damage

Below average · higher than 43% of U.S. places

Recorded about 7 times a year in the area

Inland flooding

29% of expected damage

Well below average · higher than 20% of U.S. places

Recorded about 2 times a year in the area

Tornadoes

14% of expected damage

Above average · higher than 73% of U.S. places

Hail

8% of expected damage

Well above average · higher than 92% of U.S. places

Recorded about 4 times a year in the area

Heat waves

7% of expected damage

Above average · higher than 72% of U.S. places

Recorded about 4 times a year in the area

Lower here

Ice stormsWinter weatherWildfireEarthquakesLandslidesStrong 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 Onalaska flood?

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

2paid claims since 1980

$7Kpaid to owners

0homes flooded more than once

19802026

of homes in flood zones
are insured

of all homes
are insured

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

Insurance rates: La Crosse County.

Disasters that hit Onalaska

6 federal disasters brought FEMA money here

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

Brought FEMA money into OnalaskaDeclared for La Crosse County only

2018

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

1 household applied for aid

2017

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

$139K to the City of Onalaska for repairs

2016

Severe Storms, Flooding, and Mudslides

$77K to the City of Onalaska for repairs

2008

Severe Storms, Tornadoes, and Flooding

2 households applied for aid $5K aid approved $25K to the City of Onalaska for repairs

2007

Severe Storms and Flooding

22 households applied for aid $13K aid approved

2004

Severe Storms and Flooding

4 households applied for aid $9K aid approved

La Crosse County has had 16 natural disasters declared since 1953, most often severe storms and floods.

Around Onalaska

Onalaska and the towns around it

Very lowLowModerateHighVery high

Holmenmostly cold wavesLow

Medarymostly inland floodingLow

Onalaskamostly cold wavesLow

Hamiltonmostly inland floodingLow

La Crossemostly cold wavesLow

Onalaskamostly cold wavesVery low

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. Onalaska covers 3 census tracts, combined by population.

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

FEMA’s expected losses across Onalaska total about $6.3M a year, counting buildings, people and crops.

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.