KRASNAYA POLYANA, Russia — Thick fog lingering over the mountains Monday caused the biggest weather disruptions of the Sochi Olympics so far, with a biathlon race and a snowboard event both postponed until Tuesday.

The fog rolled in over the mountains in Krasnaya Polyana on Sunday night and was still shrouding some of the Olympic skiing venues in a cloud-like mist by late Monday afternoon. That prompted organizers to call off the men’s biathlon mass-start race and men’s snowboardcross almost simultaneously.

The rescheduling didn’t seem to be a major concern for the athletes, though.

“This is standard for snowboarding and ski events. Mother Nature doesn’t always cooperate,” American snowboardcross rider Nate Holland said.

The biathlon race had already been pushed back from Sunday evening to Monday morning, and was then postponed to mid-afternoon before being called off for another day. It will now be held Tuesday at 2:30 p.m., organizers said. A decision on the women’s mass-start race still scheduled for its original 7 p.m. start was set to be made later Monday.

“Well, I am going to sleep again,” double Olympic champion Martin Fourcade tweeted in French after the race was postponed. “We’ll see each other tomorrow!”

At the Rosa Khutor Extreme Park, the snowboardcross was also first delayed then postponed. Organizers first canceled the seeding runs for the event, then pushed back the elimination races before calling it a day. The elimination races will now start at 10:30 a.m. Tuesday, with the seeding runs scrapped.

Curling

SOCHI, Russia — Britain’s women kept their chances of reaching the Olympic curling semifinals alive by beating Russia 9-6 on Monday, eliminating the host nation from the tournament.

Eve Muirhead’s world champion team has a 5-3 win-loss record and can join Canada and Sweden in the playoffs with a win over Denmark in their last round-robin game later Monday.

Muirhead’s team failed to reach the Olympic semifinals in 2010, despite being one of the favorites.

Japan defeated China 8-5, leaving both teams tied with Switzerland at 4-4. The United States (1-8) finished in last place for the second consecutive Olympic Games after losing 11-2 to South Korea.