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Tornado in Lyon County, Iowa
43 tornadoes events in the NCEI Storm Events record, 1950 to 2026. Event types counted: Tornado.
NCEI notes that Storm Data is compiled from a variety of sources including the National Weather Service, other federal, state and local agencies, the media and the public; that property and crop damage figures are estimates; and that some events are recorded by NWS forecast zone rather than by county. FEMA notes that NFIP claim records are redacted and aggregated to protect the privacy of policyholders. Storm records through 30 Jun 2026.
NCEI records 43 tornado events in Lyon County, Iowa, between 1950 and 2026, spread over 30 years.
June is the busiest month, with 14 of the recorded events. The last 20 years account for 15 events against 14 in the 20 years before, a change that reflects reporting practice as much as weather.
The county holds 1.2% of the 3,501 tornado events recorded in Iowa; its 7.3 per 100 square miles compares with 6.3 statewide.
NCEI attributes 1 death in the county to tornadoes.
By rating: 19 at (E)F0, 16 at (E)F1, 6 at (E)F2, 0 at (E)F3, 0 at (E)F4, 0 at (E)F5 and 2 unrated. Tornadoes before 2007 carry the original Fujita rating.
Compared with Iowa
| Measure | Lyon County | Iowa | US |
|---|---|---|---|
| Tornado events since 1950 | 43 | 3,501 | 81,281 |
| Per 100 square miles | 7.3 | 6.3 | 2.3 |
| Per 10,000 residents | 35.8 | 11.0 | 2.4 |
| Deaths recorded | 1 | 100 | 6,410 |
| Busiest month | June | May | May |
By year
Seasonality
0Feb
0Mar
0Apr
8May
10Jun
14Jul
9Aug
2Sep
0Oct
0Nov
0Dec
0
Magnitude distribution
Enhanced Fujita scale wind estimates
- EF0/F0
- 65–85 mph (EF0)
- EF1/F1
- 86–110 mph (EF1)
- EF2/F2
- 111–135 mph (EF2)
- EF3/F3
- 136–165 mph (EF3)
- EF4/F4
- 166–200 mph (EF4)
- EF5/F5
- over 200 mph (EF5)
- Unrated
- no rating recorded
Tornado rating as recorded (Fujita scale before February 2007, Enhanced Fujita after).
Recorded events
All 43 events, most recent first. Magnitude is hail size, tornado rating or wind speed as recorded.
| Date | Event type | Magnitude | Property damage | Crop damage | Deaths | Injuries | Geography |
|---|---|---|---|---|---|---|---|
| 28 Jul 2025 | Tornado | EF unrated | — | — | — | — | County |
| 28 Jul 2025 | Tornado | EF1 | — | — | — | — | County |
| 16 Apr 2024 | Tornado | EF1 | — | — | — | — | County |
| 30 May 2022 | Tornado | EF0 | — | — | — | — | County |
| 30 May 2022 | Tornado | EF1 | — | — | — | — | County |
| 17 Aug 2019 | Tornado | EF1 | $200K | — | — | — | County |
| 17 Jun 2014 | Tornado | EF0 | — | — | — | — | County |
| 16 Jun 2014 | Tornado | EF0 | — | — | — | — | County |
| 25 Jun 2010 | Tornado | EF2 | $500K | — | — | — | County |
| 25 Jun 2010 | Tornado | EF1 | $20K | — | — | — | County |
| 21 Jun 2009 | Tornado | EF0 | — | — | — | — | County |
| 11 Jun 2008 | Tornado | EF0 | — | — | — | — | County |
| 1 May 2008 | Tornado | EF0 | — | — | — | — | County |
| 1 May 2008 | Tornado | EF0 | — | — | — | — | County |
| 1 May 2008 | Tornado | EF1 | $10K | — | — | — | County |
| 9 May 2004 | Tornado | F0 | $1K | — | — | — | County |
| 18 Apr 2004 | Tornado | F1 | $50K | — | — | — | County |
| 24 Jun 2003 | Tornado | F0 | — | — | — | — | County |
| 12 Jun 2001 | Tornado | F0 | — | — | — | — | County |
| 9 Jul 2000 | Tornado | F1 | $50K | — | — | — | County |
| 27 Jun 1998 | Tornado | F0 | — | — | — | — | County |
| 7 Jul 1997 | Tornado | F0 | — | — | — | — | County |
| 7 Jul 1997 | Tornado | F0 | — | — | — | — | County |
| 4 Aug 1995 | Tornado | F0 | — | — | — | — | County |
| 12 Jun 1994 | Tornado | F0 | $500 | $50 | — | — | County |
| 25 Apr 1994 | Tornado | F1 | $500K | — | — | — | County |
| 7 May 1993 | Tornado | F2 | $500K | — | — | — | County |
| 23 May 1989 | Tornado | F0 | $3K | — | — | — | County |
| 7 Jun 1987 | Tornado | F0 | $250 | — | — | — | County |
| 26 Apr 1986 | Tornado | F2 | $2.5M | — | 1 | 2 | County |
| 26 Apr 1986 | Tornado | F2 | $2.5M | — | — | — | County |
| 21 Apr 1985 | Tornado | F1 | $250K | — | — | — | County |
| 21 Apr 1985 | Tornado | F0 | $250K | — | — | — | County |
| 29 May 1980 | Tornado | F0 | — | — | — | — | County |
| 6 Jul 1978 | Tornado | F2 | $2.5M | — | — | — | County |
| 19 Jun 1978 | Tornado | — | — | — | — | — | County |
| 20 May 1975 | Tornado | F1 | $3K | — | — | — | County |
| 19 Apr 1973 | Tornado | F1 | $25K | — | — | — | County |
| 16 Jul 1963 | Tornado | F1 | $25K | — | — | — | County |
| 25 Jul 1960 | Tornado | F1 | $250K | — | — | — | County |
| 19 Jun 1954 | Tornado | F2 | $25K | — | — | — | County |
| 2 Jul 1952 | Tornado | F1 | — | — | — | — | County |
| 19 Jun 1951 | Tornado | F1 | — | — | — | — | County |
Questions and answers
How many tornado events has Lyon County had?
43 events in the NCEI Storm Events record between 1950 and 2026. Reporting of tornadoes became far more complete after 1996, so early decades undercount.
When was the last recorded tornado event in Lyon County?
28 Jul 2025 (Tornado, EF1). Records reach NCEI about 120 days after the month ends.
What was the most damaging tornado event recorded in Lyon County?
The tornado of 6 Jul 1978, with property damage estimated by NCEI at $2.5M.
How does Lyon County compare with Iowa for tornado?
7.3 events per 100 square miles against 6.3 statewide; the county holds 43 of the state's 3,501 recorded events.
Provenance
NOAA NCEI Storm Events Database, yearly details files through 30 Jun 2026, public domain. County-recorded events plus zone-recorded events whose forecast zone is named for the county (marked "Forecast zone"). Population and area from the US Census Bureau (2021). Built 1 Oct 2026. See the methodology, the Tornado hub and the county page.