How Likely Is a Tornado in Jefferson County, MO?
Jefferson County, MO: what NOAA's tornado record says
Jefferson County has recorded 44 tornado touches in NOAA's 76-year database, a rate of roughly one every 1.7 years - our High band. Put another way: Jefferson County sees more tornado activity than 84% of US counties. Within Missouri alone, Jefferson County ranks 12 of 115 counties for tornado frequency.
Beyond the frequency band: violent history
36 weak and 7 significant tornadoes make up Jefferson County's 44-track record - none violent. NOAA has never logged an EF4 or EF5 crossing this county.
The dollar figure Jefferson County's rating leads to
Cost nationally: $2,890-$13,280, about $7,645 typical. Missouri has no state rebate program confirmed here; FEMA's underlying 75% cost-share exists nationwide, but applying through a state program is what usually makes it real, and none was found for Missouri this pass.
What a direct hit isn't required for
The storm that misses Jefferson County outright can still take its power out - outbreak-scale outages across Missouri are common well beyond the tracked path. A battery-backup unit handles that without a generator's setup or fuel.
What this number is, and is not
One caveat before relying on Jefferson County's number: it is county-wide, and it covers about 656 square miles, so a single touch counts the same as one in a county a fraction of that size. Weaker pre-1990s tornadoes are also documented as undercounted in NOAA's own record. Jefferson County has about 231,888 residents.