Illinois

Storm History: Williamson County, Illinois

776 episodes, 891 events since 1957

Every storm the National Weather Service has filed in Williamson County, Illinois: floods, hail, damaging wind, tornadoes, winter storms, heat and the rest, with the most serious on record. Events filed by forecast zone count for every county the zone covers.

The record

Events
891
Deaths
13
Injuries
270
Damage
$501 million
Episodes
776

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

Open the live radar over Williamson County

Every year

From 1996 the record holds 48 kinds of event with each office’s narrative; before that, tornadoes, hail and thunderstorm wind only, and before 1955 tornadoes alone.

By kind of event

Counted under the kind that heads each episode.

Kind of eventEventsDeathsInjuriesDamage
Hail12300$13 million
Tornado10810237$479 million
Dense Fog10700
Strong Wind6900$105,000
Thunderstorm Wind6600$641,000
Flash Flood5900$2.2 million
Frost/Freeze5500$30,000
Heat53130
Winter Weather5300
Winter Storm3900$1.0 million
Excessive Heat3600
Drought2900$3.5 million
Flood2110$415,000
Heavy Snow2003
Cold/Wind Chill1910
High Wind1000$505,000
Heavy Rain700
Ice Storm600$385,000
Extreme Cold/Wind Chill400
Lightning400$130,000
Funnel Cloud200
Dust Storm100$1,000

The deadliest

The costliest

Damage within this county, in the dollars of its year.

The largest hail

The largest stone in each episode, which may have fallen in a neighboring county of the same episode.

The strongest tornadoes

Every tornado in Williamson County, with its track

Every episode, newest first

Earlier years, state by state:

More

Tornadoes in Williamson CountyEvery warning in Williamson County since 1986Every county in Illinois

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24.