Grafton, WI
Local storm history & FEMA National Risk Index data
Grafton is rated Relatively Low for overall natural hazard risk — lower risk than most US counties — based on FEMA's National Risk Index for Ozaukee County, WI. The county's highest-rated hazards are cold wave, hail, and tornado.
Storm events near Grafton
NOAA-recorded tornado, hail, and flood events within 25 miles of Grafton's center, 2016–2026 — the only hazards NOAA reports with exact coordinates, so these counts are specific to Grafton 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 Ozaukee County's FEMA National Risk Index scores, covering Grafton along with the rest of the county, not a Grafton-specific figure.
| Hazard | NRI score | Rating |
|---|---|---|
| Wildfire | 19.5 | Very Low |
| Inland Flooding | 58.3 | Relatively Low |
| Coastal Flooding | 31 | Very Low |
| Earthquake | 26.4 | Very Low |
| Heat Wave | 56 | Relatively Low |
| Tornado | 59.3 | Relatively Low |
| Avalanche | — | Not Applicable |
| Cold Wave | 82.8 | Relatively Moderate |
| Drought | 21.5 | Very Low |
| Hail | 71.2 | Relatively Low |
| Hurricane | 7.5 | Very Low |
| Ice Storm | 20.6 | Very Low |
| Landslide | 15.4 | Very Low |
| Lightning | 41.4 | Relatively Low |
| Strong Wind | 31 | Relatively Low |
| Tsunami | — | Insufficient Data |
| Volcanic Activity | — | Not Applicable |
| Winter Weather | 44.2 | Relatively Low |
Source: FEMA National Risk Index v1.20.0, December 2025. See the methodology page for definitions, or the full Ozaukee County risk profile for disaster declarations, social vulnerability, and climate projection data.
Other cities in Ozaukee County:
More on Ozaukee County:
Frequently asked questions
What natural hazards is Grafton, WI at risk of?
Grafton 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 Ozaukee County, where Grafton is located, are cold wave, hail, and tornado.
What is Grafton's biggest natural hazard risk?
Cold Wave is the highest-rated hazard for Ozaukee County, where Grafton is located, scoring 82.8 out of 100 on FEMA's National Risk Index (rated "Relatively Moderate").
Is Grafton a high-risk area for natural disasters?
No — Grafton carries lower risk than most US counties for overall natural hazard risk, per FEMA's National Risk Index rating of "Relatively Low" for Ozaukee County.
Has Grafton had tornadoes, hail, or flooding?
NOAA has recorded 2 tornado, 136 hail, 56 inland flooding events within 25 miles of Grafton since 2016.