In spite of its position far inland, Strasbourg has an oceanic climate , though with less maritime influence than the milder climates of Western and Southern France. The city has warm, relatively sunny summers and cool, overcast winters. Precipitation is elevated from mid-spring to the end of summer, but remains largely constant throughout the year, totaling 631.4 mm (24.9 in) annually. On average, snow falls 30 days per year.
The second highest temperature ever recorded was 38.5 °C (101.3 °F) in August 2003, during the 2003 European heat wave. This record was broken, on June 30, 2019, when it reached 38.8 °C (101.8 °F). The lowest temperature ever recorded was −23.4 °C (−10.1 °F) in December 1938.
Strasbourg’s location in the Rhine valley, sheltered from strong winds by the Vosges and Black Forest mountains, results in poor natural ventilation, making Strasbourg one of the most atmospherically polluted cities of France. Nonetheless, the progressive disappearance of heavy industry on both banks of the Rhine, as well as effective measures of traffic regulation in and around the city have reduced air pollution in recent years.