Japan:Fog canceled Saturday morning's practice for the Japanese Grand Prix and could throw the afternoon's qualifying into difficulty.
After waiting for nearly an hour, race organizers gave up an attempt to run the 60-minute practice on the track that was wet from overnight rains.
The sport's governing body, FIA, requires that a medical helicopter be able to fly in case of accidents.
It went up briefly and the cars hurried to the track, but five minutes later the helicopter was grounded because of the weather and the cars stopped.
Cars need the practice, not only because of the need to run under wet conditions after Friday's training was dry, but also because the track is new.
The circuit replaces the venue at Suzuka, whose contract ran out last year.
Fuji Speedway, near Mount Fuji, last hosted a Formula One race in 1977 and the circuit has been renovated to prepare for the modern version of Formula One.
However Mount Fuji was not seen because of the fog that enveloped the area.
Qualifying is scheduled for Saturday afternoon. Should that be abandoned too there is a precedent for running the qualifying to determine the starting grid position on Sunday morning, hours before the 67-lap race.
In 2004 when a typhoon threatened Suzuka, all racing was canceled on Saturday and the qualifying was held on Sunday.
Ferrari's Kimi Raikkonen and Felipe Massa, who were 1-2 in the last race in Belgium, led one of Friday's session and McLaren's feuding duo of Lewis Hamilton and Fernando Alonso were on top in the other session.
The Ferrari and McLaren drivers have won all of the 14 races to date with Alonso and Raikkonen taking four each.
Two-time defending Formula One world champion Alonso has beaten Hamilton in five of the last six races, and the British driver's one-time 14-point lead has shrunk to just two, 97-95, with three races left in the season.
Hamilton is clinging to the chance to become the first rookie to take the F1 title amid a tumultuous two months that has seen McLaren embroiled in dispute over possession of technical data belonging to rival constructor Ferrari.
After being found guilty by FIA, McLaren was fined $100 million.
Even though Raikkonen and Massa trail the McLaren drivers in the driver standings, Ferrari took its 15th team title when McLaren's team points were withdrawn.
The driver's kept their points in return for providing evidence against McLaren during the meeting of the World Motor Council on September 13 that was attended by Hamilton but not Alonso.