Dewey County, Oklahoma: Natural Disaster Risk and History
Dewey County, Oklahoma has a Very Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 15.6 out of 100, higher than about 15% of US counties, with ice storms, drought and wildfires scoring highest of its 18 hazards and $5.8 million a year in expected losses.
OpenFEMA lists 33 federal disaster declarations that included Dewey County since 1973, not counting 2 for COVID-19; the latest is FM-5628-OK (Jumping Juniper Fire, declared 22 March 2026). NOAA's Storm Prediction Center recorded 55 tornadoes touching Dewey County from 1950 to 2025.
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Population 4,466 Buildings worth $999 million Area 1,019 sq mi Risk rank in Oklahoma 74 of 77 FIPS 40043
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Ice storm | Relatively High | 94.6 | $1.5 million | about once every 1.1 years | 64 |
| Drought | Relatively Moderate | 86.3 | $1.2 million | about 9 a year | 2,576 |
| Wildfire | Relatively Low | 73.6 | $215,073 | about once every 192 years | — |
| Landslide | Very Low | 54.5 | $1,731 | about once every 2.2 years | — |
| Strong wind | Relatively Low | 43.2 | $422,974 | about 4.1 a year | 155 |
| Hail | Relatively Low | 39.3 | $162,336 | about 7.9 a year | 300 |
| Tornado | Relatively Low | 39.1 | $769,198 | about once every 1.4 years | 23 |
| Cold wave | Relatively Low | 38.3 | $582,378 | about 2.8 a year | 53 |
| Heat wave | Very Low | 26.7 | $102,886 | about 7.1 a year | 106 |
| Winter weather | Relatively Low | 25.7 | $22,549 | about 9.3 a year | 177 |
| Earthquake | Very Low | 23.3 | $35,151 | about once every 893 years | — |
| Hurricane | Very Low | 11.9 | $2,427 | about once every 168 years | 2 |
| Inland flooding | Very Low | 5.7 | $753,312 | about once every 3.1 years | 9 |
| Lightning | Very Low | 1.7 | $5,623 | about 49 a year | 65,096 strikes |
| Avalanche | Not Applicable | — | — | — | — |
| Coastal flooding | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic activity | Not Applicable | — | — | — | — |
Score: FEMA's percentile among US counties that face the hazard (higher = more risk). Expected loss: FEMA's modelled average yearly loss to buildings, people (as a statistical value) and crops. How often: FEMA's annualised frequency of the hazard in the county; for some hazards it counts event-days, so it is a rough guide, not a forecast. "Not Applicable" means FEMA does not model that hazard here.
Federal disaster declarations 33
Most common: Severe Storm 18, Severe Ice Storm 8, Fire 5, Hurricane 1.
| Decade | Declarations | Incident types |
|---|---|---|
| 1970s | 2 | Flood, Severe Storm |
| 1990s | 1 | Severe Storm |
| 2000s | 12 | Severe Storm ×7, Severe Ice Storm ×3, Fire, Hurricane |
| 2010s | 13 | Severe Storm ×9, Fire ×2, Severe Ice Storm ×2 |
| 2020s | 5 | Severe Ice Storm ×3, Fire ×2 |
The last 10
Widest declarations that included Dewey County
- Severe Winter Storms (2021, DR-4587-OK): 77 Oklahoma counties designated.
- Severe Winter Storm (2021, EM-3555-OK): 77 Oklahoma counties designated.
- Severe Winter Storm (2011, EM-3316-OK): 77 Oklahoma counties designated.
Named storms in its declarations: Hurricane Katrina (2005).
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. Oklahoma also had 24 statewide declarations with no county list.
Tornado record since 1950 55
| Tornadoes touching the county | 55 |
|---|---|
| Strongest-rated | (E)F3 ×2 |
| Peak month | May (21) |
| Deadliest | 24 May 2011, EF3, 13.2 mi path, 1 killed, 2 injured |
| Longest path | 8 Apr 1952, F0, 45.9 mi path |
| Most recent | 15 Jun 2019, EF1, 3.2 mi path |
| Deaths / injuries on those paths | 1 / 9 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 24 | 19 | 9 | 2 | 0 | 0 | 1 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 14 | 13 | 5 | 5 | 6 | 5 | 7 | 0 |
Deaths and injuries are for each tornado's whole path, which can run beyond this county. F-scale ratings before February 2007, Enhanced Fujita (EF) after.
How Dewey County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| Dewey County (this page) | — | Very Low | 15.6 | Ice storm |
| Custer County | 39 km | Relatively Low | 62.0 | Ice storm |
| Blaine County | 53 km | Very Low | 32.3 | Ice storm |
| Woodward County | 54 km | Very Low | 41.6 | Ice storm |
| Major County | 56 km | Very Low | 34.2 | Ice storm |
| Roger Mills County | 70 km | Very Low | 23.2 | Drought |
Nearest by distance between county centres. Every county in Oklahoma, ranked.
Vulnerability and resilience
| Social vulnerability | Relatively Moderate 46.9 |
|---|---|
| Community resilience | Relatively Moderate 48.7 |
| Community risk factor | 1.11 |
| Expected annual loss, all hazards | $5.8 million |
FEMA scales expected losses up where social vulnerability is high (people who may find it harder to prepare, evacuate or recover) and down where community resilience is high. A factor above 1 raises the risk score. For social vulnerability a high rating is worse; for resilience a high rating is better.
Prepare for Dewey County's main hazards
- Right now: National Weather Service alerts for Oklahoma · all official warnings on Global Incident Tracker.
- Ice storm: Power outages now · Carbon monoxide in winter
- Drought: Drought monitor for Oklahoma
- Wildfire: US wildfires now · Wildfire smoke: what protects you
- Your property's flood zone: FEMA Flood Map Service Center ↗ — this page cannot tell you that.
- Official preparedness guidance: Ready.gov ↗ and your county emergency management office.
What this page shows, and what it misses
FEMA's National Risk Index rates a whole county against every other US county; it is a planning-level estimate for nationwide comparison, not a flood-zone map and not a substitute for a local risk assessment or the risk to one home. Declarations are presidential disaster, emergency and fire management declarations that named this county; state declarations and SBA or USDA designations are not included. Tornadoes are counted when the county is one of up to four listed on the track; 670 tornadoes that crossed a state line carry no county list in NOAA's file and are left out.
Federal Emergency Management Agency (FEMA), National Risk Index Dataset: National Risk Index Counties - v1.20.0 (December 2025). Retrieved from https://services.arcgis.com/XG15cJAlne2vxtgt/ArcGIS/rest/services/National_Risk_Index_Counties/FeatureServer/0/query on November 2, 2026, 1:20 PM EST. This product uses the Federal Emergency Management Agency’s National Risk Index dataset API or downloadable datasets 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).
Federal Emergency Management Agency (FEMA), OpenFEMA Dataset: Disaster Declarations Summaries - v2, retrieved from https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries on November 2, 2026, 1:21 PM EST. 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).
Tornado records: NOAA/NWS Storm Prediction Center, Severe Weather Database, tornadoes 1950–2025 (https://www.spc.noaa.gov/wcm/data/1950-2025_actual_tornadoes.csv, downloaded 2 November 2026). Public domain; not endorsed by NOAA. Compiled by Global Incident Tracker.
Questions about Dewey County
What natural disasters is Dewey County, Oklahoma most at risk from?
Dewey County, Oklahoma has a Very Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 15.6 out of 100, higher than about 15% of US counties, with ice storms, drought and wildfires scoring highest of its 18 hazards and $5.8 million a year in expected losses.
How many federal disaster declarations has Dewey County had?
OpenFEMA lists 33 federal disaster declarations that included Dewey County since 1973, not counting 2 for COVID-19; the latest is FM-5628-OK (Jumping Juniper Fire, declared 22 March 2026). Another 24 Oklahoma declarations were made statewide without a county list.
How many tornadoes have hit Dewey County?
NOAA's Storm Prediction Center recorded 55 tornadoes touching Dewey County from 1950 to 2025. The deadliest: 24 May 2011, EF3, 13.2 mi path, 1 killed, 2 injured (deaths and injuries are for the whole path).
Is the National Risk Index a flood zone map?
No. The National Risk Index is a planning-level estimate for a whole county, built for nationwide comparison. It does not tell you the flood zone or the risk of a single property: for that, look up the address on FEMA's Flood Map Service Center (msc.fema.gov) and ask your local floodplain manager.