Tornado Risk in Franklin County, IL
Franklin County's tornado history, by the numbers
19 tornado tracks have crossed Franklin County since 1957 by NOAA's count, roughly one every 4 years - the Moderate band on this site's scale. That is the 49th percentile nationally for tornado frequency. Among 102 Illinois counties in this dataset, Franklin County ranks 76 for how often a tornado touches down.
The number that matters more than frequency
Yes. Franklin County has recorded 1 EF4 or EF5 tornado - the strength FEMA's own safe-room guidance is built around, because a standard code-built house is not expected to survive those winds without a hardened room. A county can be lower-frequency overall and still carry this history.
Shelter and safe-room economics
Illinois does not currently have a confirmed state rebate layered on top of FEMA's 75% Hazard Mitigation cost-share, so a Franklin County homeowner should expect the full national range: $2,890-$13,280, $7,645 typical.
Power after the storm, not just shelter during it
Power loss after a tornado outbreak in Illinois often reaches homes the storm itself never touched. A battery-backup unit covers the outage without the fuel and venting a generator needs.
What Franklin County's figure does not tell you
Franklin County's figure is county-wide, not address-specific. Franklin County covers about 409 square miles, so a single touch here counts the same as a single touch in a county a fraction of that size. NOAA also documents that older records undercount weaker tornadoes from before Doppler radar became standard. Franklin County has about 37,033 residents.