Click on a day for an hourly weather forecast
The temperatures in Iowa City in September are comfortable with low of 13°C and and high up to 24°C.
You can expect about 3 to 8 days of rain in Iowa City during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Iowa City in September 2025.
If you’re planning to visit Iowa City in the near future, we highly recommend that you review the 14 day weather forecast for Iowa City before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -3° / -10° | 4 | 13 | 14 | 59 mm | Awful | Iowa City in January |
| February | -1° / -8° | 3 | 12 | 13 | 69 mm | Awful | Iowa City in February |
| March | 8° / 0° | 7 | 18 | 6 | 108 mm | Awful | Iowa City in March |
| April | 14° / 5° | 9 | 19 | 2 | 157 mm | Bad | Iowa City in April |
| May | 21° / 12° | 10 | 21 | 0 | 221 mm | Ok | Iowa City in May |
| June | 26° / 17° | 10 | 20 | 0 | 218 mm | Good | Iowa City in June |
| July | 28° / 18° | 7 | 24 | 0 | 141 mm | Good | Iowa City in July |
| August | 27° / 17° | 6 | 25 | 0 | 118 mm | Perfect | Iowa City in August |
| September | 24° / 13° | 6 | 24 | 0 | 109 mm | Perfect | Iowa City in September |
| October | 16° / 7° | 6 | 24 | 1 | 112 mm | Good | Iowa City in October |
| November | 8° / 1° | 5 | 23 | 3 | 86 mm | Bad | Iowa City in November |
| December | 1° / -5° | 4 | 17 | 9 | 70 mm | Awful | Iowa City in December |