Climate averages 1991–2020
Iowa City weather
in July.
A hot, wet month: the warmest and the 7th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
July is a hot month in Iowa City: daytime highs average 28.2°C and nights cool to about 19.3°C. By daytime temperature it is the warmest month of the year.
Expect about 95 mm of rain on roughly 10 days, which makes July a wet month (the 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 53 min on an average July day.
The nearest other city in this atlas is Cedar Rapids (40 km away). In July its highs average 27.7°C, 0.5°C cooler than Iowa City, with 100 mm of rain.
Among the 498 cities listed in the United States, Iowa City ranks joint 348th of 498 for the warmest July highs and joint 352nd of 498 for the driest July (rainfall, lowest first). The mean July high of those 498 cities is 30.3°C; Iowa City is 2.1°C cooler than that mean.
From July to August, average highs fall by 0.8°C to 27.4°C, and monthly rainfall rises from 95 mm to 96 mm.
The annual picture
July in context
Monthly precipitation
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Iowa City climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -1.5°C-10.3°C | -10.3°C | 39 | 7.1 | 9.510 h |
| February | 1.1°C-8.2°C | -8.2°C | 46 | 6.5 | 10.611 h |
| March | 8.7°C-1.7°C | -1.7°C | 69 | 9.1 | 11.912 h |
| April | 15.5°C4.9°C | 4.9°C | 111 | 11.8 | 13.313 h |
| May | 21.4°C11.4°C | 11.4°C | 123 | 13.4 | 14.515 h |
| June | 26.3°C17.0°C | 17.0°C | 128 | 11.7 | 15.115 h |
| July, selected | 28.2°C19.3°C | 19.3°C | 95 | 9.5 | 14.915 h |
| August | 27.4°C18.4°C | 18.4°C | 96 | 9.1 | 13.914 h |
| September | 23.7°C14.2°C | 14.2°C | 99 | 8.1 | 12.513 h |
| October | 16.6°C7.6°C | 7.6°C | 74 | 8.6 | 11.111 h |
| November | 8.7°C0.3°C | 0.3°C | 59 | 7.6 | 9.910 h |
| December | 1.4°C-6.3°C | -6.3°C | 49 | 6.9 | 9.29 h |
Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
July in nearby cities
- Cedar Rapids in JulyUnited States · 40 kmHigh 27.7°C · Low 18.8°C · 100 mm rain
- Davenport in JulyUnited States · 81 kmHigh 28.5°C · Low 19.9°C · 91 mm rain
- Des Moines in JulyUnited States · 173 kmHigh 28.7°C · Low 19.7°C · 91 mm rain
- Peoria (Illinois), United States in JulyUnited States · 195 kmHigh 28.8°C · Low 20.1°C · 96 mm rain
- Rockford in JulyUnited States · 213 kmHigh 27.6°C · Low 18.4°C · 86 mm rain
- Madison in JulyUnited States · 235 kmHigh 27.1°C · Low 17.9°C · 83 mm rain
- Bloomington (Illinois), United States in JulyUnited States · 250 kmHigh 28.2°C · Low 19.3°C · 98 mm rain
- Springfield (Illinois), United States in JulyUnited States · 261 kmHigh 29.1°C · Low 20.2°C · 91 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Iowa City) is explained once on the Iowa City year overview and on the Sources, method and limits page.