Cass County, Iowa
County storm and disaster record · FIPS 19029 · population 13,124 · 564 sq mi
NOAA's Storm Events Database holds 724 records for Cass County, Iowa from 1950 through June 30, 2026, on 421 days; the most frequent are severe thunderstorm wind events (203 records). The deadliest single record is the February 1, 2015 winter storm, filed for the forecast zone Cass, which covers the county: 1 death and $62,000 in damage in 2025 dollars. FEMA has issued 19 declarations naming the county since 1965, 17 of them for natural hazards; the latest for a natural hazard was “Severe Storms, Straight-Line Winds, and Tornadoes” on February 23, 2022.
The record, 1950 to 2026
Storm records filed for the county each year (2026 to June 30, 2026). Before 1996 NOAA recorded only tornadoes (from 1950), thunderstorm wind and hail (from 1955).
- recorded, no damage figure
- under $100,000
- $100,000 or more
- $1 million or more
- $10 million or more, or a death
- $100 million or more, or 10 deaths
- a year's colour: its recorded damage or deaths
- a year with a death
- 1955: wind and hail recorded from 1955
- 1996: all 48 event types from 1996
- Storm records
- 724on 421 days, 1950 to June 30, 2026
- Deaths recorded
- 111 injuries
- Damage, 2025 dollars
- $243Mas filed (scale steps before 1993)
- Tornadoes
- 40strongest F3
- FEMA declarations
- 19latest 2022
Source: NOAA NCEI Storm Events Database, records through June 30, 2026 (file revision 20260918); damage converted to 2025 dollars with the BLS CPI-U. Search the record at NCEI. BLS consumer price index.
What hazards hit Cass County most?
The most frequent records are severe thunderstorm wind events: 203 since 1968. 57% of its severe thunderstorm wind events since 1968 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.
| Hazard | Records | Days | First, last | Killed | Injured | Damage | Rank in state |
|---|---|---|---|---|---|---|---|
| Severe thunderstorm wind | 203 | 119 | 1968-2025 | 0 | 1 | $7.5M | 27 of 99 |
| Hail | 174 | 94 | 1971-2025 | 0 | 0 | $4.4M | 29 of 99 |
| Heavy rain | 83 | 43 | 2008-2024 | 0 | 0 | – | 9 of 99 |
| Winter storms | 72 | 69 | 1996-2025 | 1 | 0 | $9.5M | 85 of 99 |
| Floods | 51 | 35 | 1996-2019 | 0 | 0 | $44M | 79 of 99 |
| Tornadoes | 40 | 31 | 1956-2024 | 0 | 10 | $13M | 30 of 99 |
| High wind and dust storms | 34 | 34 | 1996-2025 | 0 | 0 | $1.7M | 37 of 99 |
| Drought | 32 | 32 | 1999-2024 | 0 | 0 | $156M | 33 of 99 |
| Extreme cold | 24 | 24 | 1996-2025 | 0 | 0 | $5.9M | 63 of 99 |
| Fog, smoke and funnel clouds | 5 | 5 | 2011-2025 | 0 | 0 | – | 65 of 99 |
| Heat | 4 | 4 | 2001-2019 | 0 | 0 | $177K | 61 of 99 |
| Lightning | 2 | 2 | 2018-2018 | 0 | 0 | $71K | 55 of 99 |
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 Cass County had?
NOAA records 40 tornadoes in Cass County from 1956 to 2024, the strongest rated F3, with 0 deaths and 10 injuries recorded in the county. That is 30th 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 43 tornadoes whose track touched Cass County since 1950 (NOAA's county records number 40: they file a crossing tornado once per county segment, and the two databases differ on some tracks); along their whole tracks they killed 0 people.
| Date | Tornado | Rating | Path | Killed |
|---|---|---|---|---|
| 1999-04-08 13:54, as SPC files it | Casey | F4 | 49 mi | 0 |
| 1974-05-13 16:30, as SPC files it | Grant | F3 | 10.9 mi | 0 |
| 1964-04-20 22:30, as SPC files it | Atlantic | F3 | 6.1 mi | 0 |
Map of the strongest tornado tracks in Iowa.
Every tornado record filed for Cass County (40)
| Date | Place | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2024-06-28 | Wiota, Cass County | EFU 0.3 mi x 20 yd | 0 | 0 | – |
| 2024-06-28 | Wiota, Cass County | EFU 0.4 mi x 30 yd | 0 | 0 | – |
| 2024-06-28 | Lewis, Cass County | EF0 2.44 mi x 50 yd | 0 | 0 | $2K |
| 2024-06-28 | Marne, Cass County | EFU 0.91 mi x 40 yd | 0 | 0 | $659 |
| 2024-04-16 | Anita Municipal Airport, Cass County | EF1 0.87 mi x 30 yd | 0 | 0 | $24K |
| 2023-07-12 | Marne, Cass County | EF0 2.1 mi x 75 yd | 0 | 0 | $6K |
| 2023-07-12 | Marne, Cass County | EF0 1.46 mi x 50 yd | 0 | 0 | $969 |
| 2021-12-15 | Lorah, Cass County | EF0 1.29 mi x 80 yd | 0 | 0 | $27K |
| 2021-12-15 | Lewis, Cass County | EF2 13.71 mi x 100 yd | 0 | 0 | $327K |
| 2019-07-16 | Fletcher Chapel, Cass County | EFU 1.41 mi x 30 yd | 0 | 0 | $577 |
| 2019-05-22 | Anita Municipal Airport, Cass County | EF1 1.09 mi x 50 yd | 0 | 0 | $17K |
| 2011-03-22 | Dewey, Cass County | EF1 2.84 mi x 250 yd | 0 | 0 | $197K |
| 2009-06-07 | Anita Municipal Airport, Cass County | EF0 0.17 mi x 25 yd | 0 | 0 | – |
| 2009-03-23 | Norway Center, Cass County | EF0 0.99 mi x 35 yd | 0 | 0 | $28K |
| 2009-03-23 | Cumberland, Cass County | EF0 3.45 mi x 50 yd | 0 | 0 | $344K |
| 2008-06-05 | Cumberland, Cass County | EF0 1.53 mi x 50 yd | 0 | 0 | – |
| 2007-05-06 | Griswold, Cass County | EF2 7.43 mi x 830 yd | 0 | 0 | $1.4M |
| 2004-05-08 | Lewis, Cass County | F1 7 mi x 50 yd | 0 | 0 | $159K |
| 2000-05-18 | Anita, Cass County | F0 1 mi x 30 yd | 0 | 0 | $3K |
| 1999-04-08 | Massena, Cass County | F3 7.5 mi x 1,000 yd | 0 | 0 | $330K |
| 1998-05-21 | Anita, Cass County | F1 0.5 mi x 35 yd | 0 | 0 | $139K |
| 1992-07-15 | Cass County | F0 0.1 mi x 13 yd | 0 | 0 | $250 step |
| 1990-06-12 | Cass County | F0 0.2 mi x 17 yd | 0 | 0 | $3K step |
| 1990-06-12 | Cass County | F1 1 mi x 30 yd | 0 | 0 | $250K step |
| 1987-05-31 | Cass County | F1 5 mi x 20 yd | 0 | 0 | $3K step |
| 1985-06-23 | Cass County | F1 1.5 mi x 50 yd | 0 | 1 | $250K step |
| 1985-06-23 | Cass County | F0 0.1 mi x 17 yd | 0 | 0 | – |
| 1985-06-23 | Cass County | F0 0.1 mi x 17 yd | 0 | 0 | – |
| 1984-06-07 | Cass County | F2 23 mi x 150 yd | 0 | 8 | $2.5M step |
| 1981-05-23 | Cass County | F0 | 0 | 0 | – |
| 1981-03-29 | Cass County | F1 | 0 | 0 | $25K step |
| 1980-07-04 | Cass County | F1 1.3 mi x 60 yd | 0 | 0 | $25K step |
| 1979-07-27 | Cass County | F1 1 mi x 60 yd | 0 | 0 | $25K step |
| 1979-03-18 | Cass County | F1 0.3 mi x 30 yd | 0 | 0 | $250 step |
| 1976-06-13 | Cass County | F2 8.5 mi x 100 yd | 0 | 0 | $25K step |
| 1964-08-27 | Cass County | F2 1 mi x 50 yd | 0 | 0 | $25K step |
| 1964-04-20 | Cass County | F3 6.1 mi x 350 yd | 0 | 1 | $25K step |
| 1964-04-12 | Cass County | F1 0.2 mi x 200 yd | 0 | 0 | $25K step |
| 1963-04-18 | Cass County | F2 | 0 | 0 | $25K step |
| 1956-05-29 | Cass County | F2 3.3 mi x 50 yd | 0 | 0 | $250 step |
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, 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 Cass County?
The most recent record with damage, injuries or deaths is the July 7, 2025 thunderstorm wind ($1,500 in damage in 2025 dollars).
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2025-07-20 | Funnel CloudAtlantic, Cass County | 0 | 0 | – | |
| 2025-07-07 | Thunderstorm WindMassena, Cass County | 56 kt wind | 0 | 0 | $2K |
| 2025-07-07 | Thunderstorm WindGriswold, Cass County | 50 kt wind | 0 | 0 | – |
| 2025-06-23 | Thunderstorm WindAtlantic, Cass County | 52 kt wind | 0 | 0 | – |
| 2025-06-16 | Thunderstorm WindAtlantic, Cass County | 50 kt wind | 0 | 0 | – |
| 2025-06-15 | HailGriswold, Cass County | 1.50 in hail | 0 | 0 | – |
| 2025-04-28 | Thunderstorm WindAnita, Cass County | 50 kt wind | 0 | 0 | – |
| 2025-04-17 | HailLewis, Cass County | 1.00 in hail | 0 | 0 | – |
| 2025-03-19 | High WindCass County · forecast zone Cass | 50 kt wind | 0 | 0 | – |
| 2025-03-14 | Thunderstorm WindCumberland, Cass County | 60 kt wind | 0 | 0 | – |
| 2025-03-05 | High WindCass County · forecast zone Cass | 55 kt wind | 0 | 0 | – |
| 2025-03-04 | BlizzardCass County · forecast zone Cass | 0 | 0 | – |
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
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2015-02-01 | Winter StormCass County · forecast zone Cass A major winter storm affected the entire state during the evening of 31 January into the evening of the 1 February. The northern and southern branch of the jet stream phased over the central U.S. The southern branch drew tropical moisture north into the system as the northern branch brought down colder air. Low ... | 1 | 0 | $62K | |
| 1984-06-07 | TornadoCass County | F2 23 mi x 150 yd | 0 | 8 | $2.5M step |
| 1998-05-21 | Thunderstorm WindAtlantic, Cass County A frontal boundary remained nearly stationary to the south of Iowa. Thunderstorms fired up as warm air over ran the cooler air at the surface. Storms formed over Nebraska and moved into western Iowa during the mid evening hours, then continued to advance east across the state. For the most part the storms produced ... | 0 | 1 | $100K | |
| 1985-06-23 | TornadoCass County | F1 1.5 mi x 50 yd | 0 | 1 | $250K step |
| 1964-04-20 | TornadoCass County | F3 6.1 mi x 350 yd | 0 | 1 | $25K step |
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.
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 1998-06-14 | Flash FloodAtlantic, Cass County | 0 | 0 | $5.8M | |
| 1998-06-14 | FloodCass County · forecast zone Cass | 0 | 0 | $4.9M | |
| 1997-06-21 | Thunderstorm WindCumberland, Cass County | 0 | 0 | $2.1M | |
| 2007-05-06 | TornadoGriswold, Cass County | EF2 7.43 mi x 830 yd | 0 | 0 | $1.4M |
| 2007-05-06 | FloodAnita, Cass County | 0 | 0 | $1.4M | |
| 2010-01-20 | Ice StormCass County · forecast zone Cass | 0 | 0 | $1.0M | |
| 1997-06-21 | Thunderstorm WindAtlantic, Cass County | 0 | 0 | $965K | |
| 2014-06-30 | HailAnita, Cass County | 2.00 in hail | 0 | 0 | $561K |
Before 1993 NOAA filed damage by category, not amount, so the list above starts in 1993. The highest category filed here before then (entered as $2.5M, in the dollars of the day) holds: June 7, 1984 (tornado, Cass County).
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 Cass 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).
| Hazard | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020-26 |
|---|---|---|---|---|---|---|---|---|
| Severe thunderstorm wind | 0 | 3 | 9 | 17 | 24 | 69 | 62 | 19 |
| Hail | 0 | 0 | 2 | 18 | 18 | 100 | 29 | 7 |
| Heavy rain | – | – | – | – | 0 | 5 | 68 | 10 |
| Winter storms | – | – | – | – | 18 | 25 | 18 | 11 |
| Floods | – | – | – | – | 11 | 28 | 12 | 0 |
| Tornadoes | 1 | 4 | 3 | 8 | 5 | 7 | 3 | 9 |
Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).
What time of year?
57% of its severe thunderstorm wind events since 1968 fell in May and June. The two busiest months are in violet.
The values, month by month
Jan 43 · Feb 26 · Mar 42 · Apr 81 · May 142 · Jun 141 · Jul 73 · Aug 83 · Sep 33 · Oct 26 · Nov 9 · Dec 25 (records).
Source: NOAA NCEI Storm Events Database, records by the month they began.
Federal disaster declarations for Cass County
FEMA's register lists 19 declarations that include Cass County: 16 major disasters, 3 emergencies and 0 fire management assistance declarations. Most were for flood (7) and severe storm (6).
| Declared | Number | Type | Title |
|---|---|---|---|
| 2022-02-23 | DR-4642 | Severe Storm | Severe Storms, Straight-Line Winds, and Tornadoes |
| 2020-03-23 | DR-4483 | Biological | Covid-19 Pandemic |
| 2020-03-13 | EM-3480 | Biological | Covid-19 |
| 2019-03-23 | DR-4421 | Flood | Severe Storms and Flooding |
| 2010-03-02 | DR-1880 | Severe Storm | Severe Winter Storm |
| 2010-02-25 | DR-1877 | Severe Storm | Severe Winter Storms and Snowstorm |
| 2008-05-27 | DR-1763 | Severe Storm | Severe Storms, Tornadoes, and Flooding |
| 2007-05-25 | DR-1705 | Severe Storm | Severe Storms, Flooding, and Tornadoes |
| 2007-03-30 | EM-3275 | Snowstorm | Snow |
| 2005-09-10 | EM-3239 | Hurricane | Hurricane Katrina Evacuation |
| 2004-05-25 | DR-1518 | Severe Storm | Severe Storms, Tornadoes, and Flooding |
| 1998-07-02 | DR-1230 | Flood | Severe Storms, Tornadoes and Flooding |
| 1997-11-20 | DR-1191 | Snowstorm | Severe Snowstorms |
| 1993-07-09 | DR-996 | Flood | Severe Storms & Flooding |
| 1991-12-26 | DR-928 | Severe Ice Storm | Ice Storm |
| 1991-07-12 | DR-911 | Flood | Severe Storms & Flooding |
| 1974-06-24 | DR-443 | Flood | Severe Storms & Flooding |
| 1972-09-26 | DR-354 | Flood | Severe Storms & Flooding |
| 1965-04-22 | DR-193 | Flood | Flooding |
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 Cass County had?
NOAA's Storm Events Database holds 51 flood or flash flood records for Cass County from 1996 to 2019, on 35 days, with 0 deaths. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Cass County ranks 1604th of 2,942 U.S. counties.
The National Flood Insurance Program has paid $338,000 on 57 claims filed in Cass County; the most in one year was 21 in 1998. Claims count insured losses only: uninsured flood damage is not in this file.
The values, year by year
1979: 4 · 1980: 1 · 1982: 1 · 1984: 1 · 1991: 6 · 1993: 1 · 1998: 21 · 1999: 1 · 2000: 1 · 2003: 1 · 2007: 15 · 2008: 1 · 2010: 1 · 2015: 1 · 2016: 1; the other years: 0.
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 Cass County
FEMA's National Risk Index rates Cass County Relatively Low overall, with an expected annual loss of $16.6 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.
| Hazard | Risk rating | Expected annual loss | Modeled frequency |
|---|---|---|---|
| Drought | Relatively High | $3.3M | 8.6 modeled event-days a year |
| Cold Wave | Relatively Moderate | $4.3M | 5.2 a year (modeled) |
| Hail | Relatively Moderate | $662K | 6.2 a year (modeled) |
| Tornado | Relatively Moderate | $2.5M | once in about 2 years (modeled) |
| Strong Wind | Relatively Moderate | $584K | 4.9 a year (modeled) |
| Heat Wave | Relatively Low | $775K | 7.3 modeled event-days a year |
| Landslide | Relatively Low | $3K | once in about 5 years (modeled) |
| Ice Storm | Relatively Low | $88K | about once a year (modeled) |
Source: FEMA National Risk Index, county table, December 2025 release. FEMA's National Risk Index map.
Counties that share a border with Cass County
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
- Severe thunderstorm wind in IowaThe state's severe thunderstorm wind events, 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 Cass CountyThe hazard risk calculator: 18 hazards beside the county's record
- Download Cass County's FEMA declarations (CSV)19 rows: every declaration that named the county, for your own analysis