In the Jura, it was up to -33.9°C in the “coldest area in France”

WEATHER – We came close to the national record. If the temperatures were sometimes very mild in the southern part of France this Saturday, January 4, in the east of the country the thermometer reached freezing values, often close to the record for the lowest temperature ever recorded in France.

As Météo Franc-Comtoise points out, the Jura experienced a “ Siberian cold » during the night from Friday to Saturday. At La Combe Noire in Mignovillard, “a minimum of -33.9°C was measured by the Localsat group” in this uninhabited area and considered “the coldest in France”according to this local meteorological service. In January 2023, a local record of -36.4°C was reached there.

Similar temperatures were also recorded a few kilometers from the town of Mouthe, in the Doubs department. With -28.1°C. According to Météo Franc-Comtoise, such temperatures had not been reached since “ February 2013 ».

Meteorologist Guillaume Séchet also reports on X polar temperatures (-33.1°C) recorded at the Solaison sinkhole, in Haute-Savoie. Mentioning in passing “ other impressive values » as in La Combe Noire precisely.

Proof of the big difference experienced in France this Saturday morning, it was 13°C in Bordeaux, compared to -23.4°C in Pierrefontaine-Les-Varans (Doubs) where the thermometer dropped to -23.4°C. That is a difference of almost 30°C at 8 a.m., as highlighted The Weather Channel on his social networks.

The fault of the cold holes

To understand the explanation behind these sometimes dizzying (and numbing) values, we must turn to the agrometeorologist Serge Zaka, who explains on X that this phenomenon is the result of “ cold holes » (also called “ cold holes »).

« Cold air is denser than warm air. On windless nights, it accumulates in 'holes' on the Jura plateaus. It can thus be very locally 20°C lower in the hole than on the plate », explains this specialist. According to him, these cold holes appear “ every year ».

It is also this same phenomenon which caused the national cold record in France, on January 13, 1968. A cold hole allowed the commune of Mouthe to reach -36.7°C. Record still unequaled to this day in France, even if this “ record has been approached several times and probably exceeded », according to the Météo-Contact site, specialized in “ forecasting and monitoring extreme weather phenomena » in mainland France.

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