These phenomena, which began in the early evening, lasted only a few minutes, even a few seconds, but they hit dozens of houses, tearing off roofs and forcing residents to leave their homes.
Prime Minister Elisabeth Borne on Monday sent her «support to the inhabitants of Hauts-de-France and Normandy», assuring that everything was «done to help them».
Interior Minister Gérald Darmanin must go to Bihucourt, in Pas-de-Calais, for «a situation update», said his cabinet.
The Somme and the Pas-de-Calais were placed on Sunday in yellow vigilance for thunderstorms by Météo-France, while 20 other departments were on «orange» vigilance.
In Pas-de-Calais, the national gendarmerie on Monday morning banned access to Bihucourt and Hendecourt-lès-Cagnicourt, the two municipalities most affected by what the prefecture describes as «strong gusts of tornado-type wind».
– «Uninhabitable» housing –
Entry into these two villages of around 350 inhabitants is prohibited «for security reasons and because of the extent of the damage», specifies the prefecture in a press release. «Only the inhabitants of these two villages can access it, accompanied by the security forces».
A «Departmental Operational Center» has been activated to «coordinate the action of State services».
In Bihucourt, the most affected village, many roofs were torn off and the streets were strewn with rubble, branches or pieces of sheet metal, noted an AFP journalist.
«The damage is very, very significant in this town. There was truly a corridor effect of this tornado, since it particularly impacted the center of the village. About five streets are completely devastated», affirmed on the spot the general controller of the Pas-de-Calais firefighters, Philippe Rigaud.
“A hundred homes” are according to him “concerned”. «The firefighters are marking the houses, determining which ones are at risk of eventually collapsing, because some are totally destroyed,» he added.
The Enedis network manager was also present to restore electricity, deal with destroyed cables and torn pylons.
The towns of Ô-de-Selle and especially Conty, in the Somme, were also affected.
According to Lieutenant-Colonel Lionel Tabary, «80 homes are impacted, more or less strongly» in Conty and a dozen homes are «uninhabitable» in this city of 1,800 inhabitants.
– «War scene» –
It essentially evokes torn roofs, branches and debris on the road. The roof of a school group «was completely blown off» and the Post Office «is unoccupied because the roof has been taken off».
«I am at 35 years of career, I have never seen that in the Somme», declared the firefighter, evoking «a scene of war».
«According to the testimonies, it lasted less than 5 minutes. Some speak of a minute 30 to 2 minutes. And then behind, hail rain. And after blue skies», he added .
Nearly 3,000 homes were also deprived of electricity in the Eure after the bad weather, announced the prefecture of the department, «mainly in Bernay, Beuzeville, Asnières, Grossoeuvre and Guichainville».
A total of 64 interventions were carried out by the firefighters. The event required the relocation of five adults and five children. Gusts at 136 km / h were recorded in Beuzeville.
The firefighters also carried out 107 interventions in the Nord department, in particular in Thun St-Amand, Arleux, Warlaing, Erchin and Cantin.
According to Tristan Amm, forecaster at Météo-France, episodes of this type are extremely localized and «each time, the gusts exceed 100km / h, which is already enormous in absolute terms». They perform in France «between 40 and 50 times a year».