For the first time in 140 years, the village of Mouthe – officially recognised as France’s coldest – reported a frost-free October.
A temperate autumn is additional proof of the reality of the climate crisis, weather experts say.
At an altitude ranging between 930m and 1,450m in the Jura mountains, Mouthe earned its label as France’s coldest village after recording the lowest temperature in the country on 13 January 1968 when the thermometer dropped to -36.7C.
Local records, not verified by France’s weather authority, suggest in January 1985, the temperature fell even lower to -41C.
In the past, Mouthe recorded up to 28 days of frost in October.
François Jobard, of the French weather office Météo-France, said the frost-free October in Mouthe and exceptionally warm temperatures recorded in the city of Besançon, 60 miles to the north, was additional proof of climate change.
He added that weather in region in the second half of October was warmer than the average for the last two weeks of August in the 1970s.
“Since the beginning of measurements December 1884 in Besançon. The second fortnight of October 2022 seems to be a mistake, well above all that has been observed … In 2022 we have changed gear,” Jobard tweeted.
The weather in Mouthe, in eastern France around 5km from the French-Swiss border, is dictated by its particular geographical situation, set in a hollow where cold wind stagnates between two mountain ranges.
“The Siberian cold that regularly settles here in winter is explained by the fact that the region in the east of France is marked by a continental climate which overrides the oceanic influences in case of anticyclone. In the evening, the Val de Mouthe, which is not very steep and not very wooded, does not evacuate the cold. The particular micro-climate of the peat bog accentuates the drop in temperature,” said a the local town hall spokesperson.
This summer was the second hottest in France after 2003; temperatures in September reached a record 40C in some parts of the country. This October was said to be overall the warmest since records began.