Montclus has a hot-summer Mediterranean climate (Köppen climate classificationCsa). The average annual temperature in Montclus is 13.7 °C (56.7 °F). The average annual rainfall is 951.2 mm (37.45 in) with November as the wettest month. The temperatures are highest on average in July, at around 23.2 °C (73.8 °F), and lowest in January, at around 5.2 °C (41.4 °F). The highest temperature ever recorded in Montclus was 43.8 °C (110.8 °F) on 27 June 2019; the coldest temperature ever recorded was −14.0 °C (6.8 °F) on 16 January 1985.
Climate data for Montclus (1991−2020 normals, extremes 1978−present)