Iowa has an average annual temperature of
49.8°F
(across all 11 cities) with approximately
862 mm of annual precipitation
and average humidity of 75%.
The warmest city is Council Bluffs
with average July highs of 98.6°F,
while Dubuque
is the coldest with average January lows of -14.6°F.
This page covers 45 years of NASA POWER climate data (1981–2025)
including temperature, rainfall, humidity, wind speed, and solar radiation.
Aug is typically the warmest month across Iowa with average highs around
95°F, while
Jan is the coldest with average lows near
-10.3°F.
Jun is the wettest month with approximately
123 mm of rainfall on average.
Month
Max Temp
Min Temp
Avg Temp
Rain (mm)
Humidity
Wind (m/s)
Solar (kWh/m²)
Jan
46.2°F
-10.3°F
18°F
25
85%
3.8
1.90
Feb
55.8°F
-4.2°F
25.7°F
28
81%
3.8
2.90
Mar
70.2°F
10.4°F
40.3°F
53
75%
4.0
3.80
Apr
79.7°F
23.2°F
51.4°F
84
72%
4.0
4.80
May
84.7°F
35.8°F
60.3°F
112
73%
3.3
5.60
Jun
91°F
47.7°F
69.4°F
123
73%
2.8
6.20
Jul
95°F
54.7°F
74.8°F
109
72%
2.4
6.30
Aug
95°F
52.3°F
73.8°F
102
70%
2.4
5.50
Sep
90.9°F
39.4°F
65.1°F
81
69%
2.8
4.40
Oct
81.1°F
26.1°F
53.6°F
71
71%
3.2
3.10
Nov
66.4°F
14.4°F
40.5°F
51
78%
3.5
2.10
Dec
50.7°F
-3.1°F
23.9°F
37
85%
3.5
1.60
📈 Iowa Yearly Climate Trends
🌡️ Annual Temperature Trend
State-wide avg annual high & low · Last 10 years
📈 Iowa Long-Term Climate Trends (1981–2025)
This chart shows how Iowa's average temperatures have shifted across 45 years.
Use the range buttons to focus on recent decades or view the full historical record.
Data is averaged across all 11 cities in the state.
🌧️ Annual Precipitation Trend
State-wide avg annual precipitation · Last 10 years · mm/year
🔗 Explore Cities in Iowa
Browse detailed weather history, monthly averages, and 45-year climate trends for every city in Iowa.
Dubuque is the wettest city in Iowa with approximately 904 mm of annual precipitation on average. View Dubuque weather history →
What is the warmest month in Iowa?▼
Aug is the warmest month across Iowa, with state-wide average highs of 95°F and average lows of 52.3°F.
How many cities in Iowa have weather data?▼
TownPillar has historical weather data for 11 cities in Iowa, covering 45 years of NASA POWER climate records from 1981 to 2025.
Which month has the most sunshine in Iowa?▼
Jul is the sunniest month across Iowa with an average solar radiation of 6.30 kWh/m²/day state-wide. This solar radiation data from NASA POWER is useful for solar energy planning, agriculture, and understanding seasonal sunshine availability.
Where does this climate data come from?▼
All data is sourced from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis data. It includes monthly temperature, precipitation, humidity, wind speed, and solar radiation at 0.5° × 0.625° spatial resolution.
📚 Data Source
All weather data is sourced from NASA POWER (Prediction of Worldwide Energy Resources). Data covers 45 years (1981–2025) across 11 cities in Iowa at monthly temporal resolution.