How Likely Is a Tornado in Plymouth County, IA?
Plymouth County, IA: what NOAA's tornado record says
Plymouth County has recorded 51 tornado touches in NOAA's 76-year database, a rate of roughly one every 1.5 years - our High band. Put another way: Plymouth County sees more tornado activity than 88% of US counties. Within Iowa alone, Plymouth County ranks 12 of 99 counties for tornado frequency.
Beyond the frequency band: violent history
33 weak and 16 significant tornadoes make up Plymouth County's 51-track record - none violent. NOAA has never logged an EF4 or EF5 crossing this county.
The dollar figure Plymouth County's rating leads to
Cost nationally: $2,890-$13,280, about $7,645 typical. Iowa 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 Iowa this pass.
What a direct hit isn't required for
Tornado outbreaks routinely knock out power across Iowa 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 Plymouth County's number: it is county-wide, and it covers about 863 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. Plymouth County has about 25,825 residents.