Fremont County, Iowa

What hazards hit Fremont County most?

The most frequent records are hail reports: 139 since 1955. 56% of its hail reports since 1955 fell in May and June. The rank column places the county among Iowa's counties by days with a record per 1,000 square miles of land over each hazard's complete period.

Source: NOAA NCEI Storm Events Database (county and forecast-zone records attributed to the county; a zone record shows its own totals on each county it covers). Days: dates with at least one record of the hazard in the county. Ranks: days with a record per 1,000 square miles of land (Census Bureau 2024 Gazetteer), since 1950 for tornadoes, 1955 for hail and thunderstorm wind, 1996 for the rest.

How many tornadoes has Fremont County had?

NOAA records 39 tornadoes in Fremont County from 1959 to 2026, the strongest rated F4, with 2 deaths and 24 injuries recorded in the county. That is 21st of 99 Iowa counties by days with tornadoes per 1,000 square miles since 1950. A tornado that crossed a county line is counted in each county it touched, with the length of its path inside the county.

Counted as whole tornadoes rather than county records, the Storm Prediction Center's database holds 37 tornadoes whose track touched Fremont County since 1950 (NOAA's county records number 39: they file a crossing tornado once per county segment, and the two databases differ on some tracks); along their whole tracks they killed 2 people.

Map of the strongest tornado tracks in Iowa.

Source: NOAA NCEI Storm Events Database, tornado records by county (path length in the county, maximum width); ratings as published: F scale before February 1, 2007, EF scale after. Whole-track figures: NOAA Storm Prediction Center tornado database (1950-2025). SPC severe weather database.

When was the last damaging storm in Fremont County?

The most recent record with damage, injuries or deaths is the April 1, 2019 flood ($115 million in damage in 2025 dollars).

Flooding continued on the Missouri River due to snow melt in the Dakotas and over the Northern Rockies, a few episodes of rain, and increased discharges from dams on the Missouri River over the Dakotas. In addition flooding continued due to levee breaks on the river. Towns that continued to have flooding included Bartlett, McPaul, Thurman, Percival and Hamburg. Interstate 29 remained closed with water over the road through much of the county. Iowa Highway 2 was also under water and suffered extreme damage. Businesses just west of Interstate 29 on Highway 2 were also under water.
National Weather Service event narrative, NOAA Storm Events Database (search the full record, event 823523)

Source: NOAA NCEI Storm Events Database; every record of 2025-2026 is listed, earlier ones when they caused deaths, injuries or $250,000 of damage (2025 dollars), and every tornado.

The deadliest and costliest records

A damage figure marked "step" is a record from before 1993: NOAA then filed damage by category, and the figure is the category as entered, in the dollars of that year, not an estimate of the loss.

Source: NOAA NCEI Storm Events Database: deaths and injuries direct and indirect; damage is property plus crops as estimated by the National Weather Service, converted to 2025 dollars.

Is it getting more frequent?

Records per decade for Fremont County's most frequent hazards. Counts rose everywhere after 1996, when NOAA began recording every event type, so compare decades within a hazard's complete period only (the shaded cells come before it).

Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).

What time of year?

56% of its hail reports since 1955 fell in May and June. The two busiest months are in violet.

Source: NOAA NCEI Storm Events Database, records by the month they began.

Federal disaster declarations for Fremont County

FEMA's register lists 19 declarations that include Fremont County: 17 major disasters, 2 emergencies and 0 fire management assistance declarations. Most were for flood (9) and severe storm (5).

Source: FEMA OpenFEMA Disaster Declarations Summaries (v2), declarations through October 2, 2026; one declaration is counted once however many areas it names. OpenFEMA dataset page.

How many floods has Fremont County had?

NOAA's Storm Events Database holds 86 flood or flash flood records for Fremont County from 1997 to 2026, on 69 days, with 1 death. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Fremont County ranks 869th of 2,942 U.S. counties.

The National Flood Insurance Program has paid $10.7 million on 233 claims filed in Fremont County; the most in one year was 117 in 2019. Claims count insured losses only: uninsured flood damage is not in this file.

Source: FEMA OpenFEMA NFIP Redacted Claims, as of September 8, 2026; claims by year of loss, payments in the dollars of the year paid. OpenFEMA dataset page.

FEMA's modeled risk for Fremont County

FEMA's National Risk Index rates Fremont County Very Low overall, with an expected annual loss of $6.7 million. These are FEMA's model estimates of future loss from 18 hazards, not a count of what happened; they can differ from the record above.

Source: FEMA National Risk Index, county table, December 2025 release. FEMA's National Risk Index map.

Counties that share a border with Fremont County

1. Otoe County, NE 848
2. Cass County, NE 781
3. Fremont County 536
4. Mills County 516
5. Page County 509
6. Atchison County, MO 462
7. Montgomery County 454

Source: U.S. Census Bureau county adjacency file; NOAA NCEI Storm Events Database, records since 1950. The Census Bureau's adjacency file.

Next

• Tornadoes in IowaEvery Iowa tornado since 1950 and the counties with the most per square mile
• Hail in IowaThe state's hail reports, by county, year and month
• The Iowa recordEvery hazard in the state, its deadliest events and its federal declarations
• FEMA's risk rating for each hazard in Fremont CountyThe hazard risk calculator: 18 hazards beside the county's record
• Download Fremont County's FEMA declarations (CSV)19 rows: every declaration that named the county, for your own analysis