Weather is probably a major factor when you plan your trip to Chichibu, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually August and July, with an average temperature of 22°C, while the coldest months are January and February, with an average of 3°C. The rainiest months in Chichibu are September, July, October and June, with each month seeing an average of 288 mm of rainfall.