Weather can make or break a roadtrip, so here's some data about year-round temperatures in Kolonia to help you plan yours: The hottest months are usually September and October with an average temp of 83°F, while the coldest months are March and July with an average of 82°F. The rainiest months in Kolonia are May, July, November, and June, with each month seeing an average of 16 inches of rainfall.