A spring-like warmth just days before Christmas: up to 20°C in southern France

Exceptionally high temperatures across the country
This Wednesday, 18 December, France will experience a remarkable period of mild weather, with temperatures reaching up to 8 to 10°C above seasonal averages in many areas. This phenomenon is caused by a southeast air flow bringing warm air across the country.

While a rainy front is expected in the northwest, the rest of France will enjoy sunny weather. From the Pyrenees to the Alps and along the French Riviera, clear skies will combine with temperatures reminiscent of spring.

A chilly morning, an exceptionally mild afternoon
In the morning, temperatures will remain low in the east, particularly in Dijon, where 1°C is forecast. In contrast, the northwest will already see unusually mild conditions, with 14°C in Brest and Rennes.

In the afternoon, temperatures will soar, reaching spectacular highs:

• 14°C in Paris, Bourges, and Orléans
• 15°C in Cherbourg, Nantes, and La Rochelle
• 16°C in Rennes and Bordeaux
• 17°C in Ajaccio
• 20°C across the Basque Country, including Biarritz and Bayonne

Local records may be broken, with temperatures potentially reaching 21 to 22°C in some areas.

A dramatic cooldown expected on Thursday
Despite this temporary warmth, a more active weather system will arrive on Thursday, bringing significant rainfall and a sharp drop in temperatures. Values are expected to fall below seasonal averages, marking the end of this brief spring-like episode.