Weather is probably a major factor when you plan your trip to Kewaunee, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually July and August, with an average temperature of 18°C, while the coldest months are February and January, with an average of -3°C. The snowiest months in Kewaunee are January, March, February and April, with each month seeing an average of 21 cm of snowfall.