Tornado Risk in Lemhi County, ID
Lemhi County's tornado history, by the numbers
3 tornado tracks have crossed Lemhi County since 1956 by NOAA's count, roughly one every 25.6 years - the Minimal band on this site's scale. That is the 10th percentile nationally for tornado frequency. Within Idaho alone, Lemhi County ranks 28 of 44 counties for tornado frequency.
The number that matters more than frequency
No violent (EF4-5) tornado has been recorded in Lemhi County in NOAA's 76-year database. Of its 3 recorded tracks, 3 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 Lemhi County homeowner should expect the full national range: $2,890-$13,280, $7,645 typical.
Power after the storm, not just shelter during it
A direct hit is not required for Lemhi County to lose power - outbreak-wide outages across Idaho regularly reach homes and businesses well outside the actual tracks. A battery bank covers that gap without a generator's fuel and venting needs.
What Lemhi County's figure does not tell you
Lemhi County's figure is county-wide, not address-specific. Lemhi County covers about 4,564 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. Lemhi County has about 8,397 residents.