While the department of Mayenne was not affected by Météo-France's orange thunderstorm alert, a mini-tornado formed in the town of Ernée, more precisely in the three places called Le Poirier, La Souvate and Mérole, Sunday September 17. The phenomenon, which was filmed, broadcast and commented on by several Internet users on social networks, lasted for a few minutes before disappearing. No injuries were reported, but the mini-tornado damaged several farm buildings which collapsed.
�� Other images of the tornado in west Mayenne this Sunday around 5:15 p.m. It traveled between Juvigny and Saint-Pierre-des-Landes. (© Esther Champain) pic.twitter.com/Rnp6zIFrD3
The term mini-tornado should be clarified in the coming days. Analyzes are underway to determine the power of the phenomenon. Tornadoes or mini-tornadoes, like the one that hit Mayenne on Sunday, are events linked to stormy conditions, extremely localized and therefore difficult to predict, details actu.fr.
Under certain conditions, a thunderstorm can form a supercell accompanied by very heavy precipitation, hail, or winds blowing from different directions at different altitudes. This will allow a rotational movement and can create a tornado, a column of air swirling violently on itself, which moves while remaining in contact with the ground.
Neither modeling nor observations can predict the phenomenon with certainty. But from these different factors, as the event gets closer, the forecast generally loses some uncertainty and narrows in on a more precise threat zone. Thus, it is possible to establish a probability of occurrence of the phenomenon and a risk area.
Very localized and often carrying away everything in their path, tornadoes are difficult to measure precisely since you need a weather station to do so. Their severity is expressed on a “Fujita scale”, from 0 to 5, which mainly reflects the damage caused and estimates the strength of the winds accordingly.
Not directly, since they are caused by storms. But will their frequency be affected by global warming? UN climate experts and in particular the IPCC recognized that it was difficult to establish a direct link with a possible increase in tornadoes. But warming can favor certain conditions.