Duncan, OK
Local storm history & FEMA National Risk Index data
Duncan is rated Relatively Low for overall natural hazard risk — lower risk than most US counties — based on FEMA's National Risk Index for Stephens County, OK. The county's highest-rated hazards are hail, tornado, and wildfire.
Storm events near Duncan
NOAA-recorded tornado, hail, and flood events within 25 miles of Duncan's center, 2016–2026 — the only hazards NOAA reports with exact coordinates, so these counts are specific to Duncan itself, not the whole county.
County-wide hazard risk
Every other hazard FEMA and NOAA track — including drought — is only scored at the county level. These are Stephens County's FEMA National Risk Index scores, covering Duncan along with the rest of the county, not a Duncan-specific figure.
| Hazard | NRI score | Rating |
|---|---|---|
| Wildfire | 88.5 | Relatively Low |
| Inland Flooding | 54.2 | Relatively Low |
| Coastal Flooding | — | Not Applicable |
| Earthquake | 62.6 | Relatively Low |
| Heat Wave | 82.9 | Relatively Moderate |
| Tornado | 89.8 | Relatively Moderate |
| Avalanche | — | Not Applicable |
| Cold Wave | 70.2 | Relatively Moderate |
| Drought | 74.7 | Relatively Moderate |
| Hail | 91.5 | Relatively Moderate |
| Hurricane | 30.7 | Very Low |
| Ice Storm | 88.1 | Relatively High |
| Landslide | 44.6 | Very Low |
| Lightning | 36.9 | Relatively Low |
| Strong Wind | 84.6 | Relatively High |
| Tsunami | — | Not Applicable |
| Volcanic Activity | — | Not Applicable |
| Winter Weather | 63.2 | Relatively Moderate |
Source: FEMA National Risk Index v1.20.0, December 2025. See the methodology page for definitions, or the full Stephens County risk profile for disaster declarations, social vulnerability, and climate projection data.
More on Stephens County:
Frequently asked questions
What natural hazards is Duncan, OK at risk of?
Duncan is rated Relatively Low for overall natural hazard risk by FEMA's National Risk Index — lower risk than most US counties. The highest-rated hazards for Stephens County, where Duncan is located, are hail, tornado, and wildfire.
What is Duncan's biggest natural hazard risk?
Hail is the highest-rated hazard for Stephens County, where Duncan is located, scoring 91.5 out of 100 on FEMA's National Risk Index (rated "Relatively Moderate").
Is Duncan a high-risk area for natural disasters?
No — Duncan carries lower risk than most US counties for overall natural hazard risk, per FEMA's National Risk Index rating of "Relatively Low" for Stephens County.
Has Duncan had tornadoes, hail, or flooding?
NOAA has recorded 25 tornado, 187 hail, 43 inland flooding events within 25 miles of Duncan since 2016.