The temperatures are highest on average in July, at around , and lowest in January, at around . The highest temperature ever recorded in Dourdan was  on 25 July 2019; the coldest temperature ever recorded was  on 8 January 2010.
Temperatures peak in July, with an average of around , while dropping to a low of around in January. The highest temperature ever recorded in Dourdan was  on July 25, 2019; the lowest temperature ever recorded was  on January 8, 2010.