Adams County
Population 3,617 (2025) 423 sq mi
Adams County has recorded 28 tornadoes since 1950, 71st most of 99 counties in Iowa; the most recent was on May 21, 2024.
Hazard fingerprint Each spoke is this county’s percentile among U.S. counties where that hazard occurs. How it is computed
- Tornado damage paths since 195028
At a glance
The record for Adams County in eight numbers. Each links to its section below.
Tornadoes since 1950
28
71st of 99 in Iowa
Fewer than the typical Iowa county, which has had 35
DetailsStrongest tornado
F4
April 8, 1999, 49.0 mile path
Snowiest season
61.0in
Winter of 1911-12
Tornadoes
About one every 2.7 years since 1950, 6 of them rated F3/EF3 or stronger.
Strongest
April 8, 1999
F4, 49.0 mile path
1,000 yards wide.
Deadliest
May 21, 2024
5 killed, EF4
35 injured along the whole path.
Most recent
Tuesday, May 21, 2024
EF1, 12.7 mile path
2 years ago.
Every recorded tornado
| May 21, 2024 | EF1 | 12.7 | 0 | 0 |
| May 21, 2024 | EF4 | 40.6 | 35 | 5 |
| May 21, 2024 | EF3 | 33.9 | 0 | 0 |
| Apr 26, 2024 | EF2 | 9.7 | 0 | 0 |
| Apr 16, 2024 | EF0 | 2.4 | 0 | 0 |
| Mar 5, 2022 | EF0 | 2.8 | 0 | 0 |
| Mar 5, 2022 | EFU | 1.5 | 0 | 0 |
| Mar 28, 2020 | EF1 | 7.5 | 0 | 0 |
| Jun 28, 2017 | EF0 | 1.9 | 0 | 0 |
| Jun 28, 2017 | EF1 | 3.8 | 0 | 0 |
| Aug 2, 2015 | EF1 | 5.0 | 0 | 0 |
| Apr 14, 2012 | EF2 | 16.6 | 2 | 0 |
| May 11, 2011 | EF0 | 0.4 | 0 | 0 |
| Mar 22, 2011 | EF0 | 3.1 | 0 | 0 |
| Jun 4, 2008 | EF1 | 5.6 | 0 | 0 |
| Jun 4, 2008 | EF1 | 9.5 | 0 | 0 |
| Jun 4, 2008 | EF0 | 2.3 | 0 | 0 |
| Apr 8, 2001 | F1 | 1.0 | 1 | 0 |
| Jul 16, 1999 | F0 | 0.1 | 0 | 0 |
| Apr 8, 1999 | F4 | 49.0 | 3 | 0 |
| Jul 24, 1993 | F0 | 0.2 | 0 | 0 |
| May 24, 1989 | F4 | 49.0 | 0 | 0 |
| Aug 22, 1988 | F1 | 4.2 | 0 | 0 |
| Jun 7, 1984 | F3 | 25.0 | 3 | 0 |
| Jun 14, 1981 | F0 | 0.1 | 0 | 0 |
| May 18, 1959 | F2 | 1.0 | 0 | 0 |
| Jul 14, 1958 | F3 | 14.8 | 1 | 0 |
| Apr 25, 1957 | F0 | 0.1 | 0 | 0 |
- Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Adams County: 1.
- Weak tornadoes were under-recorded before Doppler radar coverage became national in the early 1990s, so earlier decades read low. Ratings use the Fujita scale before February 2007 and the Enhanced Fujita scale after.
Storm Prediction Center severe weather database, 1950 to 2025.
Hurricanes and tropical storms
No tropical storm or hurricane has tracked within 100 miles since records began in 1851.
Wildfire and smoke
No large wildfire has been mapped here since satellite mapping began in 1984.
Smoke overhead
Smokiest year
2023: 66 days
Heavy smoke on 26 days in 2021, the most of any year.
Last 10 years
26.4 days a year
Medium or heavy smoke, 2016 to 2025.
2025
20 days
Medium or heavy smoke. 40 so far in 2026.
- A smoke day is a date on which a smoke plume traced by NOAA Hazard Mapping System analysts from satellite imagery covered this place's point (the county's population centre or the city centre). Counts here are of medium or heavy smoke. Since 2018 analysts have often drawn light smoke as one area over most of the continent, so light-smoke counts are not comparable from year to year. The plumes show smoke anywhere in the air above, not air quality at the ground, and smoke hidden by cloud is missed.
NOAA Hazard Mapping System smoke analysis, 2011 to 2026, retrieved October 30, 2026.
Floods and flood insurance
6 federal flood insurance claims since 2008, with $221,000 paid.
Most claims in one year
2008: 5 claims
$213,000 paid.
Claims by ZIP code
| 50841 | 5 | $49,000 |
Flood events since 1996
- Flash Flood26
- Heavy Rain25
- Flood14
This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026. NOAA Storm Events through 2026.
Drought
In severe drought or worse for 148 of 1,581 months since 1895 (9%); the longest spell lasted 29 months.
148
Months in severe drought or worse since 1895
84
Months in extreme drought
9%
Share of all months, severe or worse
27
Drought reports to the Weather Service since 1996
Lowest reading
August 1934
−7.95, extreme drought
Longest severe spell
29 months
May 1955 to September 1957.
Latest month
September 2026
+3.51, very wet
Last severe month: October 2003.
- The Palmer Drought Severity Index is computed by NOAA each month from the county's average temperature and precipitation, relative to the county's own climate. Zero is normal; -3 or lower is severe drought and -4 or lower extreme drought. It describes the long-term balance of moisture, not water supply or crop losses.
NOAA NCEI nClimDiv county Palmer Drought Severity Index, 1895 to September 2026, issued October 6, 2026.
Earthquakes
2 earthquakes of magnitude 2.5 or more within 50 miles since 1995; none reached magnitude 4.
0
Magnitude 2.5+ inside the county since 1973
2
Magnitude 3+ within 50 miles since 1973
0
Magnitude 4+ within 50 miles since 1900
0
Magnitude 5+ within 50 miles since 1900
Largest within 50 miles
July 16, 2004
Magnitude 3.5
6 km SSE of Riverton, Iowa; 37.4 miles away, 3.1 miles deep.
Most recent, magnitude 3 or more
July 16, 2004
Magnitude 3.5
6 km SSE of Riverton, Iowa; 37.4 miles away.
- Earthquakes of magnitude 2.5 or more in the USGS Comprehensive Catalog since 1900. Within 50 miles means the epicentre lies within 50 miles of the county boundary (or inside the county).
- Small earthquakes were under-recorded before the modern seismic networks of the 1970s and are still missed in remote areas, so early decades read low. Magnitudes are as the catalogue reports them and mix scales (moment, local and body-wave).
USGS ANSS Comprehensive Earthquake Catalog, 1900 to present, retrieved October 30, 2026.
Severe weather and other events
424 events in the National Weather Service record, 399 of them since 1996.
70
Hail reports, 1 inch or larger
5
Hail, 2 inches or larger
74
Damaging gusts, 58 mph+
62
Winter weather events since 1996
4
Heat events since 1996
23
Cold events since 1996
Largest hail
May 19, 2013
3.00 inches
Strongest measured or estimated gust
July 14, 1987
81 mph
More event types since 1996
| Lightning | 1 | 0 |
Costliest events since 1996
- Aug 1, 2003Drought, Adams$12.7 million
National Weather Service narrative
Dry weather settled in over Iowa during the month. The last widespread rain occurred on 09 July. With the increasingly dry conditions became a primary concern as the month progressed. An extended period of heat and humidity from the 15th to 25th saw highs into the 90s to over 100 degrees F. in some locations. By month's end drought indices had worsened to severe to extreme drought across south central Iowa and at least moderate drought over the remainder of the HSA. Waterloo had its driest August on record, Des Moines its 3rd driest and Ottumwa its 8th driest. A cold front brought only a brief respite from the intense heat, as temperatures rebounded into the 90s to near 100…
- May 21, 2024Tornado$1.8 million
National Weather Service narrative
The tornado entered into Adams County after clipping the northwest corner of Taylor County. Damage was immediate on the county border with damage to trees and and to farm buildings and power poles within the first few miles in the county. The tornado continued to gain in strength and size as it travelled northeast through southwest Adams county remaining in rural areas south and east of Nodaway. The tornado eventually crossed Federal Highway 34 just north of Brooks with plenty of videos showing a large funnel with debris swirling below it. As the tornado crossed State Highway 148, it gained in strength with EF2 damage becoming more common. Upon reaching the intersection of 150th…
- Apr 8, 1999Tornado$1.0 million
National Weather Service narrative
As mentioned in the narrative above, an intense low pressure formed to the southwest of Iowa. The low tracked northeast and lifted into eastern Nebraska. Ahead of the low, a strong low level jet of around 60 knots continued through the day. A nearly stationary frontal boundary extended east from the low. It lifted into southeast Nebraska during the day, but made little progress into southern Iowa. Lines of thunderstorms formed along the boundary through the day and lifted north rapidly. These storms were elevated in nature and as a result produced most of their severe weather in the form of hail. As the day unfolded, a sharp dry line was clearly evident on the satellite as early…
- May 21, 2024Tornado$1.0 million
National Weather Service narrative
The tornado entered into Adams County from Montgomery County. This tornado remained in rural areas of western and northern Adams County until lifting north of the town of Carl near the Adair County line. The tornado impacted a house on the north side of 200th street shortly after entering the county removing much of the roof with general collapse of the structure. A large hog confinement facility near the intersection of 190th and Aspen was severally damage with most buildings destroyed. EF3 damage occurred to a house along 175th Street near Cherry Avenue with all wall removed except a couple of the interior walls. The outbuildings at this location were all destroyed as well.…
- Oct 26, 1997Heavy Snow, Adams$640,000
National Weather Service narrative
The first major winter storm of the season developed over the central Rockies as a powerful upper level jet stream dove into the southern Rockies. Intense low pressure developed over northern Oklahoma, then drifted northeast on the early morning of the 26th. A cold high pressure of Arctic origin was poised to the north of Iowa. The high gradually pushed cold air south into the central U.S. causing the precipitation on the northwest edge of the storm system to change to snow. During the early morning hours, the system went convective with widespread "thundersnow" reported over the south half of Iowa. Lightning struck a tree outside of a house in Nevada causing damage to electrical…
- Nov 10, 1998High Wind, Adams$300,000
National Weather Service narrative
Iowa experienced the worst November storm system since the great storm of 9 and 10 November 1975. During the 9th, low pressure developed over southeast Colorado. The low moved across Kansas during the afternoon and evening of the 9th and deepened to about 990 mb. Warm and moist air was drawn north ahead of the low resulting in widespread across the state. Thunderstorms erupted during the late evening of the 9th, though no severe weather occurred. During the predawn hours of the 10th, a jet streak rotated around the base of the upper level low pressure area. The jet stream, combined with a tropospheric fold, resulted in explosive deepening of the low. As the low moved through…
- Sep 7, 2001Thunderstorm Wind$250,000
National Weather Service narrative
Two distinct boundaries were in place across Iowa. A cold front had slipped into the northwest part of the state and nearly bisected the state by the early evening hours. Meanwhile, an east-northeast to west-southwest boundary was in place across the central part of the state. The second boundary was left in place by the convection that occurred earlier in the day. The airmass remained quite unstable during the evening with dew point temperatures in the mid 60s to around 70. Colder air continued to slip into the state aloft with the freezing level falling just below 12,000 feet by the early evening. Another round of thunderstorms fired to the southwest of Iowa and moved into the…
- Jul 29, 2015Flood$250,000
National Weather Service narrative
Flooding was reported across much of the county with water affecting roads and low lying areas. Numerous secondary roads across the county remain closed with water flowing over them.
- Feb 24, 2007Winter Storm, Adams$250,000
National Weather Service narrative
A major winter storm affected Iowa through the 24th and 25th of February. A powerful upper low moved onto the west coast during the middle of the week, and advanced east through the Rockies during the end of the week. Strong warm air advection took place over the top of a shallow polar airmass that was in place over Iowa. The east-southeasterly flow at the surface drew cool and dry air into the state from the east, setting the stage for a significant ice storm. The main area of precipitation overspread the state during the early morning hours of the 24th and persisted through much of the 25th. Initially, very warm air aloft meant that the precipitation fell in the form of freezing…
- May 11, 2011Flash Flood$200,000
National Weather Service narrative
Several places throughout Nodaway reported 6 inches of flowing water over roads and inundating homes and businesses.
- Storm Events records before 1996 cover only tornadoes, thunderstorm wind and hail. Damage figures are as reported by the National Weather Service at the time, not adjusted for inflation.
NOAA NCEI Storm Events Database, 1950 to 2026, issued October 26, 2026.
Weather records
From Greenfield, 24.1 miles from the county’s population centre, with records from 1893.
- All-time high
- 107°FJul 5, 1911
- All-time low
- −34°FJan 12, 1912
- Warmest night
- 84°FJul 7, 1980
- Coldest day
- −15°F3 times, most recently Dec 24, 1983
- Wettest day
- 8.00 inSep 15, 1992
- Snowiest day
- 12.0 in3 times, most recently Jan 4, 1971
- Hottest year
- 1921mean 53.5°F
- Coldest year
- 1893mean 46.8°F
- Wettest year
- 201456.01 in
- Driest year
- 196618.15 in
- Snowiest season
- 61.0 in1911-12
Median first snow
November 22
Earliest: October 10, 1932
Median last snow
March 24
Latest: May 9, 1945
0 of 85 winters had no measurable snow.
Station Greenfield (USC00133438), 1,316 ft elevation, 24.1 miles from the population centre. Daily records from 1893 to October 27, 2026; 98.3% of days in the last 30 years are complete. Records at a single station can differ from a city’s official threaded record, which may combine several stations.
NOAA NCEI Global Historical Climatology Network Daily.
Federal disaster declarations
17 since 1953. The most recent: Severe Storms, Tornadoes, and Flooding, May 24, 2024.
| May 24, 2024 | Severe Storm | DR-4784-IA |
| Mar 23, 2020 | Biological | DR-4483-IA |
| Mar 13, 2020 | Biological | EM-3480-IA |
| Mar 23, 2019 | Flood | DR-4421-IA |
| Jul 14, 2014 | Severe Storm | DR-4181-IA |
| Jul 29, 2010 | Severe Storm | DR-1930-IA |
| Mar 2, 2010 | Severe Storm | DR-1880-IA |
| May 27, 2008 | Severe Storm | DR-1763-IA |
| Jan 4, 2008 | Severe Ice Storm | DR-1737-IA |
| Sep 10, 2005 | Hurricane | EM-3239-IA |
| May 25, 2004 | Severe Storm | DR-1518-IA |
| Jun 24, 1996 | Severe Storm | DR-1121-IA |
| Jul 9, 1993 | Flood | DR-996-IA |
| Oct 2, 1992 | Flood | DR-965-IA |
| Dec 26, 1991 | Severe Ice Storm | DR-928-IA |
| May 23, 1973 | Flood | DR-386-IA |
| Sep 26, 1972 | Flood | DR-354-IA |
This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
OpenFEMA Disaster Declarations Summaries, retrieved October 30, 2026. Statewide declarations are not listed.
How this compares
Where Adams County stands among 99 counties in Iowa and 3,143 in the United States.
| Tornadoes since 1950 | 28 | 71 / 99 |
| Tornadoes rated F3/EF3 or stronger | 6 | 6 / 99 |
| Tropical cyclones within 50 mi | 0 | — |
| Hurricane-strength passes within 50 mi | 0 | — |
| Wildfire acres since 1984 | 0 | — |
| Flood insurance claims | 6 | 72 / 99 |
| Flood insurance paid | $221,000 | 56 / 99 |
| Disaster declarations | 17 | 70 / 99 |
| Flood events since 1996 | 65 | 77 / 99 |
| Hail and wind events since 1996 | 192 | 87 / 99 |
| Winter storm events since 1996 | 62 | 96 / 99 |
| Reported damage since 1996 | $24.5 million | 57 / 99 |
| River crests at major flood stage | 0 | — |
| High tide flooding days a year, last 10 years | 0.0 | — |
| Months in severe drought since 1895 | 148 | 63 / 99 |
| Medium or heavy smoke days a year, last 10 years | 26.4 | 71 / 99 |
| Earthquakes M4+ within 50 mi since 1900 | 0 | — |
| Earthquakes M2.5+ in the county since 1973 | 0 | — |
Neighbouring counties
| Adair County | 34 | 0 |
| Cass County | 43 | 0 |
| Montgomery County | 31 | 0 |
| Page County | 40 | 0 |
| Ringgold County | 29 | 0 |
| Taylor County | 40 | 0 |
| Union County | 42 | 0 |
Sources and vintage
Every number on this page comes from these public records.
- Tornadoes NOAA Storm Prediction Center severe weather database, through 2025.
- Tropical cyclones NOAA National Hurricane Center HURDAT2 (Atlantic; Northeast and Central Pacific), through 2025.
- Wildfire USGS/USFS Monitoring Trends in Burn Severity, through 2026.
- Storm events NOAA NCEI Storm Events Database, through 2026.
- Flood insurance OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026.
- Declarations OpenFEMA Disaster Declarations Summaries v2, retrieved October 30, 2026.
- Weather records NOAA NCEI Global Historical Climatology Network Daily, station USC00133438.
- River crests NOAA National Weather Service, National Water Prediction Service river gauges, retrieved October 30, 2026.
- Drought NOAA NCEI nClimDiv county Palmer Drought Severity Index, through September 2026.
- Smoke NOAA NESDIS Hazard Mapping System smoke analysis, retrieved October 30, 2026.
- Earthquakes USGS ANSS Comprehensive Earthquake Catalog (ComCat), retrieved October 30, 2026.
Joins, thresholds and known limits are set out in the methodology. Found an error? Report it. Page built October 30, 2026.