Williamson County, Illinois: hazard risk
FEMA rates Williamson County's overall risk Relatively Moderate (score 85.8 of 100, higher than 85% of rated U.S. counties); 2 of its 14 hazards are rated Relatively High or Very High, led by strong wind, winter weather. Its storm record holds 892 events since 1950.
FEMA's rating for each hazard
These are FEMA's county-wide model ratings and this county's storm record. They are not an assessment of any property, address or building, and not insurance advice: a property's risk depends on its own elevation, construction and location.
FEMA gives each hazard its own rating, and a rating does not follow the score from one hazard to the next: a hazard with a higher score can carry a lower rating than another. The table sorts by FEMA's rating, then by score (0 to 100, the county against every other county for that hazard).
| Hazard | Risk rating | Score | Expected annual loss |
|---|---|---|---|
| Strong Wind | Very High | 99.1 | $7.5M |
| Winter Weather | Relatively High | 89.8 | $364K |
| Earthquake | Relatively Moderate | 96.3 | $20M |
| Heat Wave | Relatively Moderate | 90.7 | $2.9M |
| Cold Wave | Relatively Moderate | 86.9 | $5.0M |
| Ice Storm | Relatively Moderate | 81.9 | $428K |
| Tornado | Relatively Moderate | 80.3 | $3.6M |
| Hail | Relatively Moderate | 78.3 | $721K |
| Lightning | Relatively Moderate | 67.7 | $409K |
| Landslide | Relatively Low | 79.3 | $13K |
| Riverine Flooding | Relatively Low | 69.9 | $12M |
| Drought | Relatively Low | 54.2 | $178K |
| Hurricane | Very Low | 44.5 | $39K |
| Wildfire | Very Low | 14.2 | $4K |
Source: FEMA National Risk Index, December 2025 release. A model of future loss, not a count of past events. FEMA's National Risk Index map.
What the record holds
| Hazard | Records | Deaths | Damage | Rank in state | Rank in U.S. |
|---|---|---|---|---|---|
| Severe thunderstorm wind | 142 | 0 | $243M | 33rd of 102 | 872nd of 3,080 |
| Hail | 120 | 0 | $14M | 13th of 102 | 405th of 3,080 |
| Winter storms | 117 | 0 | $1.9M | 19th of 102 | 405th of 3,077 |
| Heat | 89 | 1 | – | 12th of 102 | 79th of 3,076 |
| High wind and dust storms | 86 | 0 | $826K | 9th of 102 | 124th of 3,080 |
| Extreme cold | 79 | 1 | $40K | 13th of 102 | 48th of 3,076 |
| Floods | 68 | 1 | $4.2M | 18th of 102 | 395th of 3,080 |
| Drought | 29 | 0 | $4.9M | 17th of 102 | 625th of 3,063 |
| Tornadoes | 22 | 10 | $873M | 60th of 102 | 891st of 3,080 |
| Heavy rain | 20 | 0 | – | 5th of 102 | 196th of 3,080 |
| Lightning | 3 | 0 | $171K | 48th of 102 | 1277th of 3,080 |
Source: NOAA NCEI Storm Events Database, 1950 to 2026-06-30; damage in 2025 dollars. Search the record at NCEI.
The full Williamson County record: every hazard by year and month, the deadliest events and FEMA's declarations.