Union County Climate
Union County, Iowa
Avg Annual Temp
48.8°F
Annual Precip
37.5"
Annual Snowfall
27.7"
Extreme Heat Days
18.3
days >= 90°F/yr
Monthly Temperature
Precipitation Calendar
Seasonal Overview
National Comparison
Climate Profile
About Union County Weather
Union County Sees Moderate Continental Weather
Union County's annual average temperature of 48.8°F reflects a temperate version of the continental climate. It stays cooler than the national median but avoids the most extreme cold found further north.
Slightly Warmer Than the Iowa Average
The county's average of 48.8°F is 0.8 degrees warmer than the Iowa state average. This makes it a moderately warm entry in the state's southern half.
Ample Precipitation for the Region
Union County receives 37.5 inches of precipitation annually, which is about 1.4 inches more than the state average. This consistent rainfall supports the local agricultural economy and natural greenery.
Hot Summers and Balanced Snowfall
The area experiences 18 days of extreme heat over 90°F with a July average of 74.0°F. Winters are manageable but cold, averaging 27.7 inches of annual snowfall.
Prepare for Heat and Rainfall
Residents should plan for 18 days of intense summer heat and higher-than-average precipitation. Keeping gutters clear and HVAC systems serviced will help manage the humid, rainy summers.
Frequently Asked Questions
What is the average temperature in Union County?
How much rain does Union County get?
Does it snow in Union County?
How hot does Union County get in summer?
How cold are winters in Union County?
Track your own weather in Union County
Ambient Weather personal weather stations give you hyperlocal climate data.
Sponsored
Data source: NOAA National Centers for Environmental Information (NCEI), U.S. Climate Normals 1991-2020.
Climate normals are 30-year averages of weather variables computed from 1991 to 2020. Station data is aggregated to county level using spatial averaging. Data is informational only — not a substitute for official National Weather Service forecasts or emergency weather warnings.