Iowa City Seasonal temperature break down - The average median temperature March through May is approximately 48°F with highs averaging at 59°F and lows averaging at 39°F. June through August has an approximate average median temperature of 74°F with highs averaging at 85°F, lows typically average at 65°F. Average median temperatures September through November average out at 52°F, high temperatures average out at 61°F and lows average at 44°F.
The average median temperature December through February is approximately 24°F with highs averaging at 33°F, lows average out at 16°F.
The average Iowa City annual median temperature averages out at approximately 49°F. The coldest month in Iowa City is January with a median temperature of 19°F, the average high for the month of January is 28°F with an average low of 12°F. The hottest month in Iowa City is July with an approximate median temperature of 79°F, the average high for the month of July is 89°F with an average low of 70.4°F.