Meisch House · Photo: Ammodramus · Public domainFor tornadoes, South Sioux City’s building-damage rate is in the top 2% of U.S. census tracts
On FEMA’s National Risk Index, South Sioux City gets a C+ for hazard risk: higher expected damage per building than 60% of U.S. towns, #26 of 57 in Nebraska. Most of that expected damage is river and rain flooding (66%), then tornadoes (21%). Flood insurance has paid 20 claims here since 1978.
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 stands out about South Sioux City’s natural hazards
From FEMA’s model and FEMA’s records, below.
What South Sioux City 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
Hail
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 South Sioux City’s grade
River and rain flooding is 66% of the building damage FEMA expects in South Sioux City, and South Sioux City’s rate of river and rain flooding damage is higher than 61% of U.S. census tracts. Tornadoes add 21%, at a rate in the top 2% of U.S. census tracts.
C+ #26 of 57 in Nebraska; higher expected damage per building than 60% of U.S. towns (21,298).
South Sioux City’s residents live in 4 census tracts; FEMA’s figures are combined by where they live.
The typical Nebraska town has higher expected damage than 66% of U.S. towns; within the state, South Sioux City has less expected damage per building than 55% of Nebraska towns.
In dollars, FEMA expects about $4.9M a year in losses across South Sioux City: $2.4M to buildings, the rest to people and crops.
Does South Sioux City flood? Sometimes: 20 flood claims since 1978
Every paid claim on a federal flood insurance policy in South Sioux City, from FEMA’s records: 4.0 per 1,000 homes, more than 55% of the 13,809 U.S. towns with a flood insurance record.
- The Late spring storms7 claims · $438K
- The March 2019 Midwest Flooding3 claims · $60K
South Sioux City isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Dakota County.5 federal disasters brought FEMA money to South Sioux City
Disasters that paid out in South Sioux City itself (aid to households or repair grants to the City of South Sioux City), newest first, with that year’s flood claims.
- 2024Severe Storms, Straight-line Winds, Tornadoes, and Flooding$1.8M to the City of South Sioux City for repairs1 flood claim paid that year
- 2019Severe Winter Storm, Straight-line Winds, and Flooding$857K to the City of South Sioux City for repairs9 flood claims paid that year
- 2018Severe Storms, Tornadoes, Straight-line Winds, and Flooding$31K to the City of South Sioux City for repairs
- 2011Flooding91 households applied for aid$177K aid approved$4.1M to the City of South Sioux City for repairs8 flood claims paid that year
- 2009Severe Winter Storms and Snowstorm$29K to the City of South Sioux City for repairs
Dakota County has had 13 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 South Sioux City after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the South Sioux City archive →South Sioux City and its neighbors
South Sioux City is 2nd of the 3 graded towns here, from least expected damage per building to most. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| Sioux City | C+more damage than 58% | river and rain flooding | 152 |
| South Sioux City | C+more damage than 60% | river and rain flooding | 20 |
| Dakota City | C+more damage than 61% | river and rain flooding | 5 |
Hazard risk = FEMA’s expected yearly building damage per dollar of building value, vs. the 21,298 U.S. towns we grade; the map is shaded by fifths of the same scale. Flood claims = paid federal flood insurance claims on record.
Get ready for what South Sioux City 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.
- Park in a garage or under cover when storms are forecast.
- Stay away from windows while it falls.
- Photograph roof and car damage for your insurer.
- 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 South Sioux City
Is South Sioux City at risk for natural disasters?
On FEMA’s National Risk Index, South Sioux City has higher expected damage per building than 60% of U.S. towns: C+ for hazard risk, #26 of 57 in Nebraska. Most of the expected damage is river and rain flooding (66%) and tornadoes (21%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does South Sioux City flood?
Flood insurance has paid 20 claims in South Sioux City since 1978, $770K in all, or 4.0 per 1,000 homes, more than 55% of U.S. towns with a flood insurance record. 2 properties have flooded more than once. The most claims came from Late spring storms (7).
Is South Sioux City 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 Dakota County, 9% of homes in mapped flood zones carry federal flood insurance, and 0.4% of all homes do.
How much is flood insurance in South Sioux City?
FEMA’s Community Rating System list shows no discount for South Sioux City’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 South Sioux City?
By FEMA money that reached South Sioux City, Flooding (2011): 91 households applied for aid, $177K approved, and $4.1M to the City of South Sioux City for repairs. By flood claims, Late spring storms: 7 paid, $438K.
Is South Sioux City at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (66%), and South Sioux City’s rate for it is higher than 61% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in South Sioux City.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where South Sioux City’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.