Tornado Risk in Lewis County, MO
How likely is a tornado in Lewis County, MO?
13 tornado tracks have crossed Lewis County since 1957 by NOAA's count, roughly one every 5.8 years - the Low band on this site's scale. That is the 36th percentile nationally for tornado frequency. Within Missouri alone, Lewis County ranks 99 of 115 counties for tornado frequency.
The number that matters more than frequency
No violent (EF4-5) tornado has been recorded in Lewis County in NOAA's 76-year database. Of its 13 recorded tracks, 9 were weak (EF0-1) and 4 significant (EF2-3).
Shelter and safe-room economics
Missouri does not currently have a confirmed state rebate layered on top of FEMA's 75% Hazard Mitigation cost-share, so a Lewis County homeowner should expect the full national range: $2,890-$13,280, $7,645 typical.
Power after the storm, not just shelter during it
Tornado outbreaks routinely knock out power across Missouri for days, separately from any single house getting hit. A portable battery bank keeps a fridge, phone chargers and a radio running through that gap - cheaper and faster to set up than a generator.
What Lewis County's figure does not tell you
Lewis County's figure is county-wide, not address-specific. Lewis County covers about 505 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. Lewis County has about 9,852 residents.