Heavy Rain in Dallas County, Iowa

Heavy Rain in Dallas County, Iowa: 140 recorded events between 2007 and 2024. The strongest on record measured 0. That places the county #15 nationally and #3 statewide for this hazard.

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

The busiest decade for heavy rain in Dallas County is the 2010s, when 126 of the county's 140 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 Dallas County archive, heavy rain makes up 14.5% of all recorded severe weather across 8 hazard types. Nationally the county sits at #15 for this hazard and #3 within Iowa, putting it in the 99.4 percentile of all U.S. counties.

Jun is the peak month for heavy rain in Dallas County with 38 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 350
• Hail 249
• Flood 83
• Tornado 58
• Flash Flood 53

How many heavy rain events are on record in Dallas County, Iowa?

140 heavy rain events are recorded in Dallas County between 2007 and 2024, causing 0 direct deaths.

What is the strongest heavy rain recorded in Dallas County?

The strongest heavy rain on record in Dallas County measured 0.

Where does the heavy rain data for Dallas 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.