A hailstorm in the Alps stopped Friday's stage of the Tour de France after it left the road impassable, organisers said.
Footage posted to social media showed thick layers of hail, mudslides and water rushing down the roads at Val d'Isere.
The adverse weather led organisers to stop the stage 20 kilometres from the finish and freeze riders' time at the Col d'Iseran, the toughest of the day's climb.
It meant French rider Julian Alaphilippe relinquished the coveted yellow jersey just two days ahead of the final stage in Paris.
That saw Colombian rider Egan Bernal (Team Ineos) snag the yellow jersey from Alaphilippe (Deceunick-Quick Step), who had been wearing it for the past 14 days.
With a 45 second lead over the Frenchman and just one more alpine stage before the race's finish line in Paris, Bernal, 22, is almost all but assured to be declared this year's winner.
"It's incredible. I can't believe it. I want to ride full gas tomorrow and then arrive in Paris and once I cross the line, I'll start believing this is true," the Colombian said.
"There's one last hard stage remaining. It's a short one. I'll give it all on the road. To become the first Colombian winner of the Tour de France would be amazing," he added.
French hopes to see a homegrown talent win the prestigious race — a feat last achieved in 1984 — have been dashed but Alaphilippe has "no regrets"
"Is the yellow jersey still possible? I don't think so. It was already a dream to wear it. I pursued the dream a long time, much longer than I had imagined," he told France Télévision.
Meanwhile, fellow Frenchman Thibault Pinot (Groupama-FDJ), who started the race as a favourite, was forced to abandon due to a muscle injury in his left side. He had started the stage in fifth position 1 min 50 sec behind Alaphilippe but just 20 seconds behind Bernal.
Reigning champion and Bernal's teammate, Welshman Geraint Thomas, remains in third position.
The Col d'Iseran, the highest paved road in Europe, appears to be cursed for the Tour de France. It was meant to be crossed in the opposite direction in 1996 but the stage was also shortened then, this time, because of a snowstorm.