Denison, TX
Local storm history & FEMA National Risk Index data
Denison is rated Relatively Low for overall natural hazard risk — lower risk than most US counties — based on FEMA's National Risk Index for Grayson County, TX. The county's highest-rated hazards are hail, tornado, and heat wave.
Storm events near Denison
NOAA-recorded tornado, hail, and flood events within 25 miles of Denison's center, 2016–2026 — the only hazards NOAA reports with exact coordinates, so these counts are specific to Denison 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 Grayson County's FEMA National Risk Index scores, covering Denison along with the rest of the county, not a Denison-specific figure.
| Hazard | NRI score | Rating |
|---|---|---|
| Wildfire | 86 | Relatively Low |
| Inland Flooding | 79.5 | Relatively Moderate |
| Coastal Flooding | — | Not Applicable |
| Earthquake | 66.7 | Relatively Low |
| Heat Wave | 92.7 | Relatively Moderate |
| Tornado | 92.9 | Relatively High |
| Avalanche | — | Not Applicable |
| Cold Wave | 82.2 | Relatively Moderate |
| Drought | 47.7 | Relatively Low |
| Hail | 93.4 | Relatively Moderate |
| Hurricane | 53.3 | Very Low |
| Ice Storm | 91.6 | Relatively High |
| Landslide | 60.9 | Very Low |
| Lightning | 56.2 | Relatively Low |
| Strong Wind | 55.7 | Relatively Moderate |
| Tsunami | — | Not Applicable |
| Volcanic Activity | — | Not Applicable |
| Winter Weather | 57 | Relatively Low |
Source: FEMA National Risk Index v1.20.0, December 2025. See the methodology page for definitions, or the full Grayson County risk profile for disaster declarations, social vulnerability, and climate projection data.
Other cities in Grayson County:
More on Grayson County:
Frequently asked questions
What natural hazards is Denison, TX at risk of?
Denison 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 Grayson County, where Denison is located, are hail, tornado, and heat wave.
What is Denison's biggest natural hazard risk?
Hail is the highest-rated hazard for Grayson County, where Denison is located, scoring 93.4 out of 100 on FEMA's National Risk Index (rated "Relatively Moderate").
Is Denison a high-risk area for natural disasters?
No — Denison carries lower risk than most US counties for overall natural hazard risk, per FEMA's National Risk Index rating of "Relatively Low" for Grayson County.
Has Denison had tornadoes, hail, or flooding?
NOAA has recorded 21 tornado, 258 hail, 55 inland flooding events within 25 miles of Denison since 2016.