Photo: Jared Winkler · CC BY-SA 4.0For tornadoes, Atlantic’s building-damage rate is in the top 1% of U.S. census tracts
On FEMA’s National Risk Index, Atlantic gets a B− for hazard risk: higher expected damage per building than 54% of U.S. towns, #94 of 140 in Iowa. Most of that expected damage is river and rain flooding (64%), then tornadoes (23%). Flood insurance has paid 17 claims here since 1979.
Graded on FEMA’s expected yearly building damage per dollar of building value (NRI v1.20, December 2025), weighted by where residents live; flood claims are shown, not graded. How hazard risk is graded
What Atlantic 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
Tornadoes
Strong wind
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.
What’s behind Atlantic’s grade
River and rain flooding is 64% of the building damage FEMA expects in Atlantic, and Atlantic’s rate of river and rain flooding damage is higher than 52% of U.S. census tracts. Tornadoes add 23%, at a rate in the top 1% of U.S. census tracts.
B− #94 of 140 in Iowa; higher expected damage per building than 54% of U.S. towns (21,298).
Atlantic’s residents live in 2 census tracts; FEMA’s figures are combined by where they live.
The typical Iowa town has lower expected damage than 57% of U.S. towns; within the state, Atlantic has more expected damage per building than 67% of Iowa towns.
In dollars, FEMA expects about $5.8M a year in losses across Atlantic: $2.4M to buildings, the rest to people and crops.
Does Atlantic flood? Sometimes: 17 flood claims since 1979
Every paid claim on a federal flood insurance policy in Atlantic, from FEMA’s records: 4.8 per 1,000 homes, more than 59% of the 13,809 U.S. towns with a flood insurance record.
Atlantic isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Cass County.3 federal disasters brought FEMA money to Atlantic
Disasters that paid out in Atlantic itself (aid to households or repair grants to the City of Atlantic), newest first, with that year’s flood claims.
- 2008Severe Storms, Tornadoes, and Flooding27 households applied for aid$62K aid approved
- 2007Severe Storms, Flooding, and Tornadoes51 households applied for aid$42K aid approved
- 2004Severe Storms, Tornadoes, and Flooding5 households applied for aid$4K aid approved
Cass County has had 16 natural disasters declared by the President since 1953, most often floods, then severe storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Old photos of Atlantic after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Atlantic archive →Get ready for what Atlantic 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.
- 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.
- Trim dead limbs over the house and driveway.
- Tie down trash cans and outdoor furniture.
- Stay clear of downed lines and call the utility.
- 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 Atlantic
Is Atlantic at risk for natural disasters?
On FEMA’s National Risk Index, Atlantic has higher expected damage per building than 54% of U.S. towns: B− for hazard risk, #94 of 140 in Iowa. Most of the expected damage is river and rain flooding (64%) and tornadoes (23%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Atlantic flood?
Flood insurance has paid 17 claims in Atlantic since 1979, $89K in all, or 4.8 per 1,000 homes, more than 59% of U.S. towns with a flood insurance record.
Is Atlantic 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 Cass County, 20% of homes in mapped flood zones carry federal flood insurance, and 0.3% of all homes do.
How much is flood insurance in Atlantic?
FEMA’s Community Rating System list shows no discount for Atlantic’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 Atlantic?
By FEMA money that reached Atlantic, Severe Storms, Tornadoes, and Flooding (2008): 27 households applied for aid, $62K approved.
Is Atlantic at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (64%), and Atlantic’s rate for it is higher than 52% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Atlantic.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Atlantic’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.