Low pressure system tracking over intensely heated land results in large hailstones and frequent lightning
After several days of intense heat, large parts of France were hit by a major outbreak of severe thunderstorms on Wednesday night as powerful supercells swept north-east across the country.
A low pressure system that originated near Portugal tracked over the unusually warm Bay of Biscay towards northern France late on Wednesday, bringing a strong upper-level disturbance over land that had been intensely heated through the day. As a result, several long-lived supercells formed, producing large hailstones, frequent lightning, damaging winds and torrential rainfall.
Hailstones of up to 8cm in diameter caused significant damage to property, crops and vehicles, while rainfall totals up to 150mm in places brought flash flooding, including in Paris. Ferocious winds also brought down pylons and trees, killing two people and bringing power cuts to 110,000 homes.
Just north-east of Paris, a gust of 140kph was recorded, the strongest of the outbreak, while supercells elsewhere produced winds up to 126kph. One especially long-lived storm sustained gusts of 90-135kph over several hundred miles as it travelled from the south-west corner of the country to its north-east.
