Storms, floods and disasters in Thornton
Thornton isn’t graded for hazard risk: Thornton has 292 residents; we grade towns of 1,000 or more.
What Thornton faces
Each hazard’s share of the building damage FEMA expects here, and how its rate compares with the rest of the country.
River and rain flooding
Earthquakes
Ice storms
Tornadoes
Shares are of FEMA’s expected building damage, the measure the grade uses; ranks compare each hazard’s building-damage rate with all 85,154 U.S. census tracts. In FEMA’s terms, river and rain flooding is FEMA’s “Inland Flooding” (rivers and streams overflowing their banks, or rain overwhelming drainage). FEMA defines coastal flooding as high or rising tides and storm surge, so surge damage is counted there. Drought isn’t listed: FEMA counts its losses in crops only.
Does Thornton flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Thornton. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Thornton isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Calhoun County.2 federal disasters brought FEMA money to Thornton
Disasters that paid out in Thornton itself (aid to households or repair grants to the City of Thornton), newest first, with that year’s flood claims.
- 2004Severe Storms and Flooding$23K to the City of Thornton for repairs
- 2000Severe Winter Ice Storm$20K to the City of Thornton for repairs
Calhoun County has had 18 natural disasters declared by the President since 1953, most often severe storms, then winter storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Also 1 FEMA wildfire suppression grant (Fire Management Assistance, not a disaster declaration) for fires in Calhoun County, 2026–2026.
Old photos of Thornton after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Thornton archive →Get ready for what Thornton faces
A short kit for the hazards that drive the building damage here, what to check before you buy, and where neighbors get alerts.
- Turn around at flooded roads: a foot of moving water can carry off a car.
- Flood insurance usually takes 30 days to start, so buy it before the forecast.
- Keep papers and medicines up high, in a grab-and-go bag.
- Drop, cover and hold on.
- Strap tall furniture and the water heater to the wall.
- Know how to shut off the gas.
- Ice brings down trees and lines: plan for days without power.
- Run a generator outside, far from doors and windows.
- Keep sand or salt by the door.
- Pick your spot now: the lowest floor, an inside room, no windows.
- A watch means be ready; a warning means take cover now.
- Keep shoes and a flashlight by the bed.
- Look up the address on FEMA’s flood map.
- Ask the seller or landlord whether it has ever flooded, and what flood insurance costs there.
- Get a flood insurance quote early: policies usually start 30 days after you buy.
Know where neighbors sign up for alerts? Add it to the Handbook so everyone has it.
Questions about natural hazards in Thornton
Is Thornton in a flood zone?
Flood zones are drawn street by street, so the answer depends on the address: look it up on FEMA’s flood map. In Calhoun County, 0.2% of all homes carry federal flood insurance.
How much is flood insurance in Thornton?
FEMA’s Community Rating System list shows no discount for Thornton’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
What was the biggest storm in Thornton?
By FEMA money that reached Thornton, Severe Storms and Flooding (2004): $23K to the City of Thornton for repairs.
Storm stories
Memories, warnings and help from neighbors in Thornton.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Thornton’s residents lived in the 2020 census; 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. Homes: Census ACS 2020–24. Preparedness tips: Ready.gov. FEMA’s model is an average of expected damage, not a forecast. How hazard risk is graded.