Hail in Jefferson County, Iowa

Hail in Jefferson County, Iowa: 93 recorded events between 1960 and 2026. The strongest on record measured 3.75. That places the county #1,525 nationally and #89 statewide for this hazard.

Reporting practice changed over time — early decades are undercounted, not calmer.

The busiest decade for hail in Jefferson County is the 2010s, when 35 of the county's 93 recorded events were logged. Comparing decades is useful for spotting active periods, but the earliest years are thin because systematic reporting for this hazard began later.

Within the Jefferson County archive, hail makes up 36.3% of all recorded severe weather across 8 hazard types. Nationally the county sits at #1,525 for this hazard and #89 within Iowa, putting it in the 50.7 percentile of all U.S. counties.

Apr is the peak month for hail in Jefferson County with 22 recorded events, while Jan is the quietest. Seasonality here is a property of the archive as much as the climate: reports cluster where population and spotter networks are densest.

• Thunderstorm Wind 118

How many hail events are on record in Jefferson County, Iowa?

93 hail events are recorded in Jefferson County between 1960 and 2026, causing 0 direct deaths.

What is the strongest hail recorded in Jefferson County?

The strongest hail on record in Jefferson County measured 3.75.

Where does the hail data for Jefferson County come from?

All events come from the NOAA/NCEI Storm Events Database, the federal public-domain archive of severe weather reports. Dates are UTC, damage is as reported and not inflation-adjusted, and the most recent entries may still be revised.