Edern has an oceanic climate (Köppen climate classificationCfb). The average annual temperature in Edern is 11.8 °C (53.2 °F). The average annual rainfall is 1,327.9 mm (52.28 in) with January as the wettest month. The temperatures are highest on average in August, at around 18.0 °C (64.4 °F), and lowest in January, at around 6.5 °C (43.7 °F). The highest temperature ever recorded in Edern was 38.0 °C (100.4 °F) on 9 August 2003; the coldest temperature ever recorded was −10.5 °C (13.1 °F) on 2 January 1997.
Climate data for Edern (1981–2010 averages, extremes 1989−2016)