Johnson County, Missouri

What hazards hit Johnson County most?

The most frequent records are hail reports: 292 since 1956. 44% of its hail reports since 1956 fell in April and May. The rank column places the county among Missouri'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 Johnson County had?

NOAA records 34 tornadoes in Johnson County from 1960 to 2017, the strongest rated F2, with 1 death and 12 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 33 tornadoes whose track touched Johnson County since 1950 (NOAA's county records number 34: they file a crossing tornado once per county segment, and the two databases differ on some tracks); along their whole tracks they killed 1 person.

Map of the strongest tornado tracks in Missouri.

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 Johnson County?

The most recent record with damage, injuries or deaths is the June 28, 2024 lightning (1 death and 1 injury).

A 53 year old man was struck by lightning in the parking lot at the conclusion of the Holden, MO Rodeo. The lightning strike was fatal.
National Weather Service event narrative, NOAA Storm Events Database (search the full record, event 1281055)

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 Johnson 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?

44% of its hail reports since 1956 fell in April and May. The two busiest months are in violet.

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

Federal disaster declarations for Johnson County

FEMA's register lists 21 declarations that include Johnson County: 15 major disasters, 6 emergencies and 0 fire management assistance declarations. Most were for severe storm (10) and flood (4).

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 Johnson County had?

NOAA's Storm Events Database holds 141 flood or flash flood records for Johnson County from 1996 to 2020, on 117 days, with 1 death. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Johnson County ranks 1723rd of 2,942 U.S. counties.

The National Flood Insurance Program has paid $307,000 on 44 claims filed in Johnson County; the most in one year was 8 in 2008. 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 Johnson County

FEMA's National Risk Index rates Johnson County Relatively Low overall, with an expected annual loss of $24.3 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 Johnson County

1. Jackson County 1,806
2. Cass County 898
3. Johnson County 820
4. Pettis County 595
5. Henry County 582
6. Lafayette County 563

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 MissouriEvery Missouri tornado since 1950 and the counties with the most per square mile
• Hail in MissouriThe state's hail reports, by county, year and month
• The Missouri recordEvery hazard in the state, its deadliest events and its federal declarations
• FEMA's risk rating for each hazard in Johnson CountyThe hazard risk calculator: 18 hazards beside the county's record
• Download Johnson County's FEMA declarations (CSV)21 rows: every declaration that named the county, for your own analysis