How Likely Is a Tornado in Clark County, SD?
Clark County, SD: what NOAA's tornado record says
Clark County has recorded 37 tornado touches in NOAA's 76-year database, a rate of roughly one every 2.1 years - our Elevated band. Put another way: Clark County sees more tornado activity than 77% of US counties. Within South Dakota alone, Clark County ranks 20 of 66 counties for tornado frequency.
Beyond the frequency band: violent history
28 weak and 9 significant tornadoes make up Clark County's 37-track record - none violent. NOAA has never logged an EF4 or EF5 crossing this county.
The dollar figure Clark County's rating leads to
Cost nationally: $2,890-$13,280, about $7,645 typical. South Dakota 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 South Dakota this pass.
What a direct hit isn't required for
Tornado outbreaks routinely knock out power across South Dakota 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 this number is, and is not
One caveat before relying on Clark County's number: it is county-wide, and it covers about 958 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. Clark County has about 3,974 residents.