How Likely Is a Tornado in Armstrong County, PA?
Armstrong County's tornado history, by the numbers
Armstrong County has recorded 11 tornado touches in NOAA's 76-year database, a rate of roughly one every 6.9 years - our Low band. Put another way: Armstrong County sees more tornado activity than 32% of US counties. Within Pennsylvania alone, Armstrong County ranks 45 of 67 counties for tornado frequency.
Beyond the frequency band: violent history
1 tornado touching Armstrong County reached violent (EF4-5) strength since 1950. That single fact carries more weight for the shelter decision than the county's overall frequency band.
The dollar figure Armstrong County's rating leads to
Cost nationally: $2,890-$13,280, about $7,645 typical. Pennsylvania 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 Pennsylvania this pass.
What a direct hit isn't required for
The storm that misses Armstrong County outright can still take its power out - outbreak-scale outages across Pennsylvania 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 Armstrong County's number: it is county-wide, and it covers about 653 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. Armstrong County has about 63,679 residents.