Overview
- Stations across the north reported exceptionally mild readings on Monday morning, including 15°C in Nantes, 14–15°C in Paris, and 13°C in Brest, with anomalies locally 10–13°C above seasonal norms.
- Highs have reached the high teens and about 20°C in the southwest, including Biarritz, with springlike scenes reported on Atlantic beaches and in Basque Country towns.
- The freezing level has lifted to roughly 3,200–3,300 m, accelerating snowmelt below about 3,000 m and prompting warnings of heightened avalanche danger from mountain forecasters.
- Météo‑France and other experts say the setup stems from an Atlantic depression and an anticyclonic ridge drawing very mild air from Iberia and the subtropical Atlantic, with climate warming amplifying the anomalies.
- Outlooks from Météo‑France and La Chaîne Météo indicate the mild pattern will persist through the week and could last toward mid‑December, even as passing Atlantic systems bring cloud, rain and wind to the northwest.