Weather is probably a major factor when you plan your trip to Käru, and keep 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 temp of 60°F, while the coldest months are January and February with an average of 26°F. The snowiest months in Käru are November, December, January, and February, with each month seeing an average of 9 inches of snowfall.