Monona County, Iowa
County storm and disaster record · FIPS 19133 · population 8,738 · 694 sq mi
NOAA's Storm Events Database holds 516 records for Monona County, Iowa from 1950 through June 30, 2026, on 380 days; the most frequent are hail reports (144 records). The deadliest single record is the June 11, 2008 tornado: 4 deaths and 48 injuries. FEMA has issued 20 declarations naming the county since 1965, 18 of them for natural hazards; the latest for a natural hazard was “Severe Winter Storm” on May 21, 2025.
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
- 516on 380 days, 1950 to June 30, 2026
- Deaths recorded
- 569 injuries
- Damage, 2025 dollars
- $749Mas filed (scale steps before 1993)
- Tornadoes
- 30strongest F4
- FEMA declarations
- 20latest 2025
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 Monona County most?
The most frequent records are hail reports: 144 since 1958. 43% of its hail reports since 1958 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 |
|---|---|---|---|---|---|---|---|
| Hail | 144 | 96 | 1958-2026 | 0 | 0 | $626K | 54 of 99 |
| Severe thunderstorm wind | 136 | 106 | 1963-2026 | 0 | 2 | $2.7M | 63 of 99 |
| Winter storms | 69 | 64 | 1996-2025 | 0 | 5 | – | 98 of 99 |
| Extreme cold | 54 | 54 | 1996-2026 | 0 | 0 | – | 8 of 99 |
| Tornadoes | 30 | 23 | 1953-2024 | 4 | 62 | $677M | 83 of 99 |
| High wind and dust storms | 27 | 27 | 1996-2026 | 0 | 0 | $51K | 65 of 99 |
| Floods | 23 | 20 | 1996-2024 | 0 | 0 | $69M | 98 of 99 |
| Heat | 15 | 15 | 1999-2026 | 0 | 0 | – | 23 of 99 |
| Drought | 10 | 10 | 2012-2013 | 0 | 0 | – | 92 of 99 |
| Fog, smoke and funnel clouds | 8 | 7 | 1996-2025 | 1 | 0 | – | 61 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 Monona County had?
NOAA records 30 tornadoes in Monona County from 1953 to 2024, the strongest rated F4, with 4 deaths and 62 injuries recorded in the county. 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 30 tornadoes whose track touched Monona County since 1950 (NOAA's county records number 30, the same count); along their whole tracks they killed 4 people.
| Date | Tornado | Rating | Path | Killed |
|---|---|---|---|---|
| 2008-06-11 17:27, as SPC files it | Little Sioux to Moorhead | EF3 | 12.96 mi | 4 |
| 1986-07-28 17:30, as SPC files it | Maskell to JacksonCrossed IA, NE | F4 | 52.5 mi | 0 |
| 2011-04-09 18:20, as SPC files it | Mapleton | EF3 | 3.38 mi | 0 |
Map of the strongest tornado tracks in Iowa.
Every tornado record filed for Monona County (30)
| Date | Place | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2024-04-26 | Soldier, Monona County | EF1 3.29 mi x 250 yd | 0 | 0 | – |
| 2024-04-26 | Moorhead, Monona County | EF0 1.47 mi x 100 yd | 0 | 0 | – |
| 2024-04-26 | Preparation, Monona County | EF0 1.14 mi x 50 yd | 0 | 0 | – |
| 2013-10-04 | Albaton, Monona County | EF2 4.89 mi x 250 yd | 0 | 0 | – |
| 2012-04-14 | Grant Center, Monona County | EF0 0.4 mi x 25 yd | 0 | 0 | – |
| 2011-06-20 | Moorhead, Monona County | EF1 7.13 mi x 300 yd | 0 | 0 | – |
| 2011-04-09 | Mapleton, Monona County | EF3 3.38 mi x 1,200 yd | 0 | 14 | – |
| 2008-06-11 | Blencoe, Monona County | EF3 7.49 mi x 440 yd | 4 | 48 | – |
| 2008-06-11 | Mapleton, Monona County | EF0 0.26 mi x 60 yd | 0 | 0 | – |
| 2008-05-29 | Moorhead, Monona County | EF1 3.8 mi x 200 yd | 0 | 0 | – |
| 2001-08-17 | Onawa, Monona County | F0 4 mi x 20 yd | 0 | 0 | $8K |
| 2001-08-17 | Whiting, Monona County | F0 0.2 mi x 30 yd | 0 | 0 | – |
| 2001-06-13 | Whiting, Monona County | F0 0.1 mi x 30 yd | 0 | 0 | – |
| 1999-05-16 | Ute, Monona County | F1 6.5 mi x 100 yd | 0 | 0 | $213K |
| 1998-07-06 | Blencoe, Monona County | F0 | 0 | 0 | – |
| 1998-06-23 | Whiting, Monona County | F0 2 mi x 50 yd | 0 | 0 | – |
| 1998-06-23 | Whiting, Monona County | F2 2 mi x 50 yd | 0 | 0 | – |
| 1998-05-21 | Castana, Monona County | F0 0.2 mi x 50 yd | 0 | 0 | – |
| 1992-06-16 | Monona County | F0 0.1 mi x 20 yd | 0 | 0 | $250 step |
| 1991-05-28 | Monona County | F2 5 mi x 60 yd | 0 | 0 | $250K step |
| 1987-07-05 | Monona County | F0 0.2 mi x 13 yd | 0 | 0 | – |
| 1986-07-28 | Monona County | F4 1 mi x 73 yd | 0 | 0 | $250M step |
| 1977-08-15 | Monona County | 0 | 0 | – | |
| 1968-06-24 | Monona County | 0 | 0 | – | |
| 1968-06-24 | Monona County | 0 | 0 | – | |
| 1967-06-08 | Monona County | F1 5.1 mi x 300 yd | 0 | 0 | $25K step |
| 1965-09-09 | Monona County | F2 10.2 mi x 100 yd | 0 | 0 | $250K step |
| 1965-09-09 | Monona County | F1 1 mi x 100 yd | 0 | 0 | $25K step |
| 1962-05-18 | Monona County | F1 1.9 mi x 200 yd | 0 | 0 | $25K step |
| 1953-03-21 | Monona County | F1 10.9 mi x 600 yd | 0 | 0 | $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.
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 Monona County?
The most recent record with damage, injuries or deaths is the December 24, 2025 dense fog (1 death).
Widespread dense fog reduced visibility to near 0 across Monona County. The Iowa State Patrol reported fog was present at a two-vehicle accident near the intersection of 130th Street and Walnut Avenue east of Mapleton at approximately 7:41 PM CST on December 25th. An eastbound vehicle attempted to turn around in the roadway and was struck by a second vehicle. The crash resulted in one fatality (indirect).
National Weather Service event narrative, NOAA Storm Events Database (search the full record, event 1298352)
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2026-06-29 | HeatMonona County · forecast zone Monona | 0 | 0 | – | |
| 2026-05-17 | Thunderstorm WindTiconic, Monona County | 54 kt wind | 0 | 0 | – |
| 2026-03-15 | High WindMonona County · forecast zone Monona | 50 kt wind | 0 | 0 | – |
| 2026-03-06 | HailBlencoe, Monona County | 1.50 in hail | 0 | 0 | – |
| 2026-01-23 | Extreme Cold/Wind ChillMonona County · forecast zone Monona | 0 | 0 | – | |
| 2026-01-21 | High WindMonona County · forecast zone Monona | 50 kt wind | 0 | 0 | – |
| 2025-12-24 | Dense FogMonona County · forecast zone Monona | 1 | 0 | – | |
| 2025-12-18 | High WindMonona County · forecast zone Monona | 50 kt wind | 0 | 0 | – |
| 2025-12-10 | High WindMonona County · forecast zone Monona | 56 kt wind | 0 | 0 | – |
| 2025-11-28 | Winter StormMonona County · forecast zone Monona | 0 | 0 | – | |
| 2025-11-25 | High WindMonona County · forecast zone Monona | 50 kt wind | 0 | 0 | – |
| 2025-08-09 | Thunderstorm WindBlencoe, Monona County | 63 kt wind | 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 |
|---|---|---|---|---|---|
| 2008-06-11 | TornadoBlencoe, Monona County This tornado tragically hit a boyscout camp north of Little Sioux Iowa killing 4 young scouts. The tornado initially touched down in Burt county Nebraska, crossed into Harrison county Iowa near mile marker 97 on Interstate 29, and then finally crossed into Monona county Iowa about 4 miles north of Little Sioux. In ... | EF3 7.49 mi x 440 yd | 4 | 48 | – |
| 2025-12-24 | Dense FogMonona County · forecast zone Monona Widespread dense fog reduced visibility to near 0 across Monona County. The Iowa State Patrol reported fog was present at a two-vehicle accident near the intersection of 130th Street and Walnut Avenue east of Mapleton at approximately 7:41 PM CST on December 25th. An eastbound vehicle attempted to turn around in the ... | 1 | 0 | – | |
| 2011-04-09 | TornadoMapleton, Monona County A tornado caused extensive damage in the Mapleton area with about 100 houses destroyed and many others severely damaged in a 12 to 15 block area on the southwest side of town. This caused the displacement of around 500 to 600 people. Most garages and stand alone structures were destroyed. In addition, large trees were ... | EF3 3.38 mi x 1,200 yd | 0 | 14 | – |
| 2010-02-14 | Winter WeatherMonona County · forecast zone Monona Snow, mostly light, combined with northwest winds which increased to 25 to 35 mph. The strong winds and snow caused widespread blowing and drifting snow and poor visibilities beginning on 2/14. After a temporary break in the afternoon and early evening on the 14th, visibilities deteriorated again late in the evening ... | 0 | 5 | – | |
| 2008-07-06 | Thunderstorm WindOnawa, Monona County Thunderstorm wind gusts estimated at over 60 mph blew some trees down on top of campers at the Lewis and Clark State Park, causing 2 minor injuries. Some campers in the area were also rolled due to the winds. | 55 kt wind | 0 | 2 | – |
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 1996-07-16 | FloodMonona County · forecast zone Monona | 0 | 0 | $54M | |
| 2011-08-01 | FloodAlbaton, Monona County | 0 | 0 | $6.6M | |
| 2019-03-13 | FloodMapleton Municipal Airport, Monona County | 0 | 0 | $4.8M | |
| 2007-05-05 | Flash FloodOnawa, Monona County | 0 | 0 | $2.0M | |
| 2024-06-24 | FloodAlbaton, Monona County | 0 | 0 | $1.2M | |
| 1994-08-07 | Thunderstorm WindMapleton, Monona County | 0 | 0 | $1.1M | |
| 1999-05-16 | TornadoUte, Monona County | F1 6.5 mi x 100 yd | 0 | 0 | $213K |
| 1994-10-06 | HailUte, Monona County | 2.75 in hail | 0 | 0 | $119K |
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 $250M, in the dollars of the day) holds: July 28, 1986 (tornado, Monona 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 Monona 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 |
|---|---|---|---|---|---|---|---|---|
| Hail | 1 | 5 | 4 | 6 | 27 | 57 | 32 | 12 |
| Severe thunderstorm wind | 0 | 3 | 11 | 22 | 39 | 33 | 17 | 11 |
| Winter storms | – | – | – | – | 8 | 27 | 22 | 12 |
| Extreme cold | – | – | – | – | 11 | 19 | 18 | 6 |
| Tornadoes | 1 | 6 | 1 | 2 | 7 | 6 | 4 | 3 |
| High wind and dust storms | – | – | – | – | 10 | 3 | 6 | 8 |
Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).
What time of year?
43% of its hail reports since 1958 fell in May and June. The two busiest months are in violet.
The values, month by month
Jan 49 · Feb 36 · Mar 35 · Apr 43 · May 65 · Jun 91 · Jul 71 · Aug 56 · Sep 19 · Oct 10 · Nov 9 · Dec 32 (records).
Source: NOAA NCEI Storm Events Database, records by the month they began.
Federal disaster declarations for Monona County
FEMA's register lists 20 declarations that include Monona County: 17 major disasters, 3 emergencies and 0 fire management assistance declarations. Most were for severe storm (8) and flood (7).
| Declared | Number | Type | Title |
|---|---|---|---|
| 2025-05-21 | DR-4870 | Winter Storm | Severe Winter Storm |
| 2024-06-24 | DR-4796 | Severe Storm | Severe Storms, Flooding, 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 |
| 2013-07-02 | DR-4126 | Severe Storm | Severe Storms, Tornadoes, and Flooding |
| 2011-06-27 | DR-1998 | Flood | Flooding |
| 2011-05-05 | DR-1977 | Severe Storm | Severe Storms, Tornadoes, and Straight-Line Winds |
| 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 |
| 1998-07-02 | DR-1230 | Flood | Severe Storms, Tornadoes and Flooding |
| 1996-08-21 | DR-1133 | Severe Storm | Severe Storms, and Flooding |
| 1993-07-09 | DR-996 | Flood | Severe Storms & Flooding |
| 1990-05-26 | DR-868 | Flood | Severe Storms & Flooding |
| 1974-06-24 | DR-443 | 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 Monona County had?
NOAA's Storm Events Database holds 23 flood or flash flood records for Monona County from 1996 to 2024, on 20 days, with 0 deaths. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Monona County ranks 1907th of 2,942 U.S. counties.
The National Flood Insurance Program has paid $701,000 on 30 claims filed in Monona County; the most in one year was 13 in 2011. Claims count insured losses only: uninsured flood damage is not in this file.
The values, year by year
1993: 1 · 1996: 2 · 2007: 2 · 2011: 13 · 2012: 1 · 2019: 5 · 2024: 6; 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 Monona County
FEMA's National Risk Index rates Monona County Very Low overall, with an expected annual loss of $8.7 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.
| Hazard | Risk rating | Expected annual loss | Modeled frequency |
|---|---|---|---|
| Drought | Relatively Moderate | $1.6M | 26 modeled event-days a year |
| Hail | Relatively Moderate | $1.0M | 6.1 a year (modeled) |
| Landslide | Relatively Low | $11K | once in about 3 years (modeled) |
| Wildfire | Relatively Low | $112K | once in about 291 years (modeled) |
| Tornado | Relatively Low | $1.7M | once in about 2 years (modeled) |
| Ice Storm | Relatively Low | $64K | about once a year (modeled) |
| Strong Wind | Relatively Low | $412K | 4.3 a year (modeled) |
| Cold Wave | Relatively Low | $509K | 6.1 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 Monona 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
- 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 Monona CountyThe hazard risk calculator: 18 hazards beside the county's record
- Download Monona County's FEMA declarations (CSV)20 rows: every declaration that named the county, for your own analysis