Plus 26°C in Pau, 23.6°C in Biarritz, 23.4°C in Tarbes, 24.4°C in Orthez… Nighttime heat levels “exceptional” For the month of November, they were registered during the night of Sunday, November 24th to Monday, November 25th. Consequences of global warming and the Foehn effect, highlights Météo-France.
the night was “Extremely mild throughout the country and even more so in the southwest”explained Matthieu Sorel, climatologist at the meteorological organization, to Agence France-Presse. The phenomenon is explained by the presence of a “South wind everywhere”what does it bring “a great sweetness”, “accentuated by the Foehn effect” in the Pyrenees-Atlantiques, Landes and Hautes-Pyrénées, under the influence of the Pyrenean relief.
The Foehn effect, which can occur at any time of the year, occurs when wind crosses a mountain barrier and experiences a “Significant warming of the air mass”. “This is what we observed last night, when the temperature reached 26.3°C in the middle of the night in Pau”Mr. Sorel explained.
“A marker of climate change”
The Foehn effect was also observed over the weekend in Brittany. “It was three degrees hotter on the north coast (…) only on the south coast, since this air mass was elevated by the Armorican relief and then descended towards the Emerald Coast.where “nocturnal softness records” were surpassed locally during the period, with 15.6°C for example on the island of Bréhat.
Late Monday morning, the wind was picking up. “Tipping over and the foehn effect stopping”continued the climatologist, so the temperature “it’s going downhill”with 14°C for example in Biarritz.
The temperatures observed last night reached “Very, very high levels, very impressive” for the month of November, the climatologist emphasizes. “Air masses like those, for this time of year, are something we don’t see without climate change”explained, “We have temperatures well above normal everywhere”15°C in Lille, 16°C in Paris, 17°C in Besançon.
Globally, “We have small cold anomalies”as illustrated by the recent episode of early winter, with significant snowfall in the northern half of France last Thursday, and “very large warm anomalies”, “It is effectively a marker of the climate change we are experiencing”underlines Mathieu Sorel.