Tornado Risk in Clark County, ID
Clark County's tornado history, by the numbers
8 tornado tracks have crossed Clark County since 1964 by NOAA's count, roughly one every 9.5 years - the Low band on this site's scale. That is the 23rd percentile nationally for tornado frequency. Idaho has 44 counties in this dataset; Clark County ranks 8 of them by frequency.
The number that matters more than frequency
No violent (EF4-5) tornado has been recorded in Clark County in NOAA's 76-year database. Of its 8 recorded tracks, 8 were weak (EF0-1) and 0 significant (EF2-3).
Shelter and safe-room economics
Idaho does not currently have a confirmed state rebate layered on top of FEMA's 75% Hazard Mitigation cost-share, so a Clark County homeowner should expect the full national range: $2,890-$13,280, $7,645 typical.
Power after the storm, not just shelter during it
The storm that misses Clark County outright can still take its power out - outbreak-scale outages across Idaho are common well beyond the tracked path. A battery-backup unit handles that without a generator's setup or fuel.
What Clark County's figure does not tell you
Clark County's figure is county-wide, not address-specific. Clark County covers about 1,763 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. Clark County has about 794 residents.