Oliver County, North Dakota
County storm and disaster record · FIPS 38065 · population 1,874 · 722 sq mi
NOAA's Storm Events Database holds 376 records for Oliver County, North Dakota from 1950 through June 30, 2026, on 289 days; the most frequent are hail reports (109 records). 189 of them are forecast-zone records, which the National Weather Service files once per zone: a county covered by several zones receives each one, so a single storm can add several records on the same day. The most damaging was the April 2, 2010 winter storm ($1.3 million in 2025 dollars). FEMA has issued 22 declarations naming the county since 1966, 20 of them for natural hazards; the latest for a natural hazard was “Severe Storms, Straight-Line Winds, and Tornadoes” on September 1, 2026.
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
- 376on 289 days, 1950 to June 30, 2026
- Deaths recorded
- 03 injuries
- Damage, 2025 dollars
- $11Mas filed (scale steps before 1993)
- Tornadoes
- 10strongest F2
- FEMA declarations
- 22latest 2026
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 Oliver County most?
The most frequent records are hail reports: 109 since 1974. 68% of its hail reports since 1974 fell in June and July. The rank column places the county among North Dakota'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 | 109 | 65 | 1974-2025 | 0 | 0 | $843K | 24 of 53 |
| Winter storms | 96 | 94 | 1996-2026 | 0 | 2 | $7.8M | 10 of 53 |
| Severe thunderstorm wind | 54 | 38 | 1976-2026 | 0 | 0 | $732K | 32 of 53 |
| High wind and dust storms | 53 | 53 | 1996-2026 | 0 | 0 | $67K | 4 of 53 |
| Extreme cold | 26 | 25 | 1996-2025 | 0 | 0 | – | 23 of 53 |
| Floods | 11 | 10 | 1997-2021 | 0 | 0 | $978K | 19 of 53 |
| Drought | 10 | 10 | 2021-2022 | 0 | 0 | – | 12 of 53 |
| Tornadoes | 10 | 10 | 1990-2025 | 0 | 1 | $576K | 43 of 53 |
| Fog, smoke and funnel clouds | 5 | 4 | 2008-2023 | 0 | 0 | – | 34 of 53 |
| Heat | 1 | 1 | 2011-2011 | 0 | 0 | – | 20 of 53 |
| Wildfires | 1 | 1 | 2006-2006 | 0 | 0 | – | 7 of 53 |
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 Oliver County had?
NOAA records 10 tornadoes in Oliver County from 1990 to 2025, the strongest rated F2, with 0 deaths and 1 injury 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 12 tornadoes whose track touched Oliver County since 1950 (NOAA's county records number 10: 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.
Map of the strongest tornado tracks in North Dakota.
Every tornado record filed for Oliver County (10)
| Date | Place | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2025-06-27 | Hannover, Oliver County | EFU 3.35 mi x 100 yd | 0 | 0 | – |
| 2020-07-07 | Sanger, Oliver County | EF1 0.22 mi x 50 yd | 0 | 0 | $11K |
| 2017-07-21 | Sanger, Oliver County | EF0 0.17 mi x 25 yd | 0 | 0 | – |
| 2004-08-23 | Center, Oliver County | F0 | 0 | 0 | – |
| 2000-11-01 | Center, Oliver County | F1 5 mi x 50 yd | 0 | 0 | – |
| 2000-06-11 | Hensler, Oliver County | F0 3 mi x 40 yd | 0 | 0 | – |
| 1999-06-13 | Hannover, Oliver County | F1 29 mi x 50 yd | 0 | 0 | – |
| 1998-05-13 | Center, Oliver County | F0 0.1 mi x 20 yd | 0 | 0 | – |
| 1996-05-30 | Mandan, Oliver County | F0 4 mi x 10 yd | 0 | 0 | – |
| 1990-06-18 | Oliver County | F2 6 mi x 93 yd | 0 | 1 | $250K 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 Oliver County?
The most recent record with damage, injuries or deaths is the June 27, 2025 hail ($100,000 in damage in 2025 dollars).
A window was broken, roofing was damaged, and the shop and barn were severely dented.
National Weather Service event narrative, NOAA Storm Events Database (search the full record, event 1263544)
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2026-06-07 | Thunderstorm WindCenter, Oliver County | 52 kt wind | 0 | 0 | – |
| 2026-04-03 | Heavy SnowOliver County · forecast zone Oliver | 0 | 0 | – | |
| 2026-03-12 | High WindOliver County · forecast zone Oliver | 52 kt wind | 0 | 0 | – |
| 2026-01-15 | High WindOliver County · forecast zone Oliver | 52 kt wind | 0 | 0 | – |
| 2025-12-17 | High WindOliver County · forecast zone Oliver | 63 kt wind | 0 | 0 | – |
| 2025-12-09 | High WindOliver County · forecast zone Oliver | 52 kt wind | 0 | 0 | – |
| 2025-06-27 | TornadoHannover, Oliver County | EFU 3.35 mi x 100 yd | 0 | 0 | – |
| 2025-06-27 | HailHannover, Oliver County | 3.50 in hail | 0 | 0 | – |
| 2025-06-27 | HailHannover, Oliver County | 3.00 in hail | 0 | 0 | – |
| 2025-06-27 | HailHannover, Oliver County | 2.50 in hail | 0 | 0 | – |
| 2025-06-27 | HailHannover, Oliver County | 2.50 in hail | 0 | 0 | – |
| 2025-06-27 | HailHannover, Oliver County | 3.00 in hail | 0 | 0 | $100K |
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 |
|---|---|---|---|---|---|
| 1997-01-09 | BlizzardOliver County · forecast zone Oliver The second blizzard in less than 1 week brought North Dakota to a virtual standstill. This blizzard didn't bring as much snow as the first storm, but the winds gusted from the northwest as high at 40 mph and they lasted for 3 days. Snowfall amounts from this storm varied from 1-2 inches in the southwest to 2-4 inches ... | 0 | 1 | $2.8M | |
| 1997-01-04 | BlizzardOliver County · forecast zone Oliver The first blizzard of 1997 hit east-central North Dakota on the morning of the 4th. The blizzard was preceeded by freezing rain that lasted most of the day before switching over to snow. The snow became so heavy that the highway department pulled the plows off of the roads the evening of the 4th and all day on the ... | 0 | 1 | $460K | |
| 1990-06-18 | TornadoOliver County | F2 6 mi x 93 yd | 0 | 1 | $250K 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 |
|---|---|---|---|---|---|
| 2010-04-02 | Winter StormOliver County · forecast zone Oliver | 0 | 0 | $1.3M | |
| 2010-01-25 | BlizzardOliver County · forecast zone Oliver | 0 | 0 | $434K | |
| 2014-09-04 | HailCenter, Oliver County | 2.75 in hail | 0 | 0 | $374K |
| 2014-07-21 | Thunderstorm WindCenter, Oliver County | 70 kt wind | 0 | 0 | $125K |
| 2025-06-27 | HailHannover, Oliver County | 3.00 in hail | 0 | 0 | $100K |
| 2014-07-06 | Thunderstorm WindHannover, Oliver County | 74 kt wind | 0 | 0 | $75K |
| 2019-08-06 | HailHannover, Oliver County | 2.00 in hail | 0 | 0 | $63K |
| 2015-07-23 | Thunderstorm WindCenter, Oliver County | 65 kt wind | 0 | 0 | $62K |
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 $250K, in the dollars of the day) holds: June 18, 1990 (tornado, Oliver 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 Oliver 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 | 0 | 0 | 2 | 10 | 20 | 28 | 29 | 20 |
| Winter storms | – | – | – | – | 19 | 28 | 31 | 18 |
| Severe thunderstorm wind | 0 | 0 | 2 | 0 | 6 | 16 | 16 | 14 |
| High wind and dust storms | – | – | – | – | 2 | 17 | 16 | 18 |
| Extreme cold | – | – | – | – | 2 | 7 | 13 | 4 |
| Floods | – | – | – | – | 1 | 5 | 4 | 1 |
Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).
What time of year?
68% of its hail reports since 1974 fell in June and July. The two busiest months are in violet.
The values, month by month
Jan 37 · Feb 23 · Mar 31 · Apr 17 · May 23 · Jun 69 · Jul 67 · Aug 38 · Sep 9 · Oct 13 · Nov 19 · Dec 30 (records).
Source: NOAA NCEI Storm Events Database, records by the month they began.
Federal disaster declarations for Oliver County
FEMA's register lists 22 declarations that include Oliver County: 19 major disasters, 3 emergencies and 0 fire management assistance declarations. Most were for severe storm (10) and flood (8).
| Declared | Number | Type | Title |
|---|---|---|---|
| 2026-09-01 | DR-4934 | Severe Storm | Severe Storms, Straight-Line Winds, and Tornadoes |
| 2025-09-11 | DR-4888 | Severe Storm | Severe Storm, Tornadoes, and Straight-Line Winds |
| 2022-07-13 | DR-4660 | Severe Storm | Severe Winter Storm and Flooding |
| 2020-04-01 | DR-4509 | Biological | Covid-19 Pandemic |
| 2020-03-13 | EM-3477 | Biological | Covid-19 |
| 2011-04-07 | EM-3318 | Flood | Flooding |
| 2010-04-21 | DR-1901 | Severe Storm | Severe Winter Storm |
| 2010-02-26 | DR-1879 | Severe Storm | Severe Winter Storm |
| 2009-03-24 | DR-1829 | Severe Storm | Severe Storms and Flooding |
| 2005-11-21 | DR-1616 | Snowstorm | Severe Winter Storm and Record and/Or Near Record Snow |
| 2005-09-13 | EM-3247 | Coastal Storm | Hurricane Katrina Evacuation |
| 2000-06-27 | DR-1334 | Severe Storm | Severe Storms, Flooding and Ground Saturation |
| 1997-04-07 | DR-1174 | Flood | Severe Flooding,Severe Winter Storms, Snowmelt, Spring Rains |
| 1997-01-12 | DR-1157 | Severe Storm | Severe Winter Storms and Blizzard Conditions |
| 1996-06-05 | DR-1118 | Severe Storm | Severe Storms,Flooding, & Ice Jams |
| 1994-07-01 | DR-1032 | Severe Storm | Severe Storms, Flooding |
| 1993-07-26 | DR-1001 | Flood | Severe Storms & Flooding |
| 1979-04-26 | DR-581 | Flood | Severe Storms, Snowmelt & Flooding |
| 1978-04-17 | DR-554 | Flood | Storms, Ice Jams, Snowmelt & Flooding |
| 1970-06-05 | DR-287 | Flood | Severe Storms & Flooding |
| 1969-04-18 | DR-256 | Flood | Flooding |
| 1966-07-09 | DR-220 | Flood | Severe Storms & 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 Oliver County had?
NOAA's Storm Events Database holds 11 flood or flash flood records for Oliver County from 1997 to 2021, on 10 days, with 0 deaths. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Oliver County ranks 2436th of 2,942 U.S. counties.
The National Flood Insurance Program has paid $68,000 on 8 claims filed in Oliver County; the most in one year was 2 in 1979. Claims count insured losses only: uninsured flood damage is not in this file.
The values, year by year
1978: 1 · 1979: 2 · 1993: 1 · 1994: 1 · 1997: 2 · 2009: 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 Oliver County
FEMA's National Risk Index rates Oliver County Very Low overall, with an expected annual loss of $2.6 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 |
|---|---|---|---|
| Winter Weather | Relatively Low | $72K | 19 a year (modeled) |
| Hail | Relatively Low | $266K | 2.6 a year (modeled) |
| Ice Storm | Relatively Low | $56K | about once a year (modeled) |
| Cold Wave | Relatively Low | $508K | 15 a year (modeled) |
| Wildfire | Very Low | $51K | once in about 2,044 years (modeled) |
| Drought | Very Low | $5K | 20 modeled event-days a year |
| Tornado | Very Low | $134K | once in about 4 years (modeled) |
| Landslide | Very Low | $19 | once in about 6 years (modeled) |
Source: FEMA National Risk Index, county table, December 2025 release. FEMA's National Risk Index map.
Counties that share a border with Oliver 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 North DakotaEvery North Dakota tornado since 1950 and the counties with the most per square mile
- Hail in North DakotaThe state's hail reports, by county, year and month
- The North Dakota recordEvery hazard in the state, its deadliest events and its federal declarations
- FEMA's risk rating for each hazard in Oliver CountyThe hazard risk calculator: 18 hazards beside the county's record
- Download Oliver County's FEMA declarations (CSV)22 rows: every declaration that named the county, for your own analysis