Every spring and autumn, locals from a handful of departments in the south-west of France brace themselves for the vent d’autan, a wind whose uncanny characteristics are said to ‘rendre fou’ (drive a person crazy).
The longstanding belief of the wind’s craziness-inducing powers is mostly based on centuries-long observations of behavioural changes, mainly irritable moods, in people living around Castres and Albi (Tarn), Revel and Toulouse (Haute-Garonne), Agen (Lot-et-Garonne) and Cahors (Lot).
The peak periods for the phenomenon are from March to April and September and October, with each windy episode lasting from one to dozens of days.
“When the vent d’autan blows, the loonies from Albi dance,” the local expression goes.
Another belief was that the wind was a mitigating factor in murders during vent d’autan periods.
A weather map shows gusts (rafales) in March of this yearLa Chaîne Météo
So apparently whoever faces the vent d’autan is two steps away from madness. But are they, really?
“There is no consensus around it,” said Paul-Frédéric Casset, a weather forecaster at Occitanie radio station, 100% Radio.
“It is a boisterous, irregular, all-over-the-place whirling wind. This is what drives people crazy,” he said, giving his take on the question.
“When it lands and blows, there is a change in atmospheric pressure, something that can be felt by people prone to migraines,” said Mr Casset.
That is because the wind takes the Lauragais corridor, south-east of Toulouse, and passes by mountains loaded with crystal rocks, mainly between the Montagne d’Alaric and the Montagne Noire. It scratches some of their crystals and charges itself with positive ions, which cause irritation.
The fabled effects could also be attributed to the wind’s deceptiveness.
It can quickly change from a slow 10km/h to 90km/h, even reaching triple-digit speeds that can derail trains, as happened on May 4, 1916 in Revel.
Last March 20, Mr Casset clocked a wind speed of 151.3km/h in Dourgne (Tarn), a record for a vent d’autan.
Many studies have been conducted to analyse some of the effects on people’s health. Doctors, psychologists and psychiatrists have all shared their findings and theories.
It was connected to an increase in throat infections and heart-attacks, according to a study conducted by Dr Dominique Rey on 786 patients hospitalised at Mazamet hospital between October 1980 and October 1981.
“It is the sensorial overexcitement that explains why people are irritated. It certainly does not explain deliriums,” psychiatrist Daniel Ajzenberg told La Dépêche newspaper in an article in 2000.
As for the murders? It is bogus, he added.
One obstetrician also quoted in the article said he witnessed a greater birth rate during vent d’autan periods. The lower atmospheric pressure liberates electrolytes contained in the amniotic fluid, favouring labour, he explained.
And researchers at the Rangueil University Hospital in Toulouse in 1983 told La Dépêche that the wind "has an adverse effect on people with a psychiatric history who are more weather-sensitive".
“The only advice I give is to take showers. I am not kidding. It will unload the positive ions,” advised Mr Casset.
