If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Keokuk: The hottest months are usually July and August with an average temp of 73°F, while the coldest months are January and February with an average of 33°F. The snowiest months in Keokuk are January, December, November, and February, with each month seeing an average of 6 inches of snowfall.