Qualifying for Sunday's Japanese Grand Prix was postponed to the morning of the race on Saturday after pouring rain made track conditions too treacherous for drivers.
The start of the hour-long session at Suzuka was pushed back three times at half-hour intervals, with the safety car making several test runs in a cloud of spray, until fading light made a postponement inevitable.
Conditions are expected to improve overnight, with Sunday forecast to be dry.
A spokeswoman for the governing International Automobile Federation (FIA) said qualifying would start at 1000 local (0100GMT) on Sunday.
Normal parc ferme conditions would apply from the start of qualifying with the cars weighed and checked as normal afterwards.
It will be the second time that qualifying has had to be shifted to Sunday at Suzuka. In 2004 typhoon Ma-on blew through the area, forcing the teams to batten down the hatches until race day.
Saturday's final practice had already been washed out, with just two drivers setting a time as others abandoned their efforts with the rain lashing down.
OPTIMISM VERSUS REALITY
Groups of drenched fans, many of whom had camped out at the circuit overnight, had stayed huddled under umbrellas in open grandstands in a triumph of optimism over reality while others trudged through the nearby fun-fair.
Mechanics in the team garages sailed makeshift model boats down the pit lane, while drivers peered out into the gloom and waved at the crowd or made swimming gestures.
Others turned to social network Twitter, offering regular updates and insight from the pit wall along with jokes to ease the boredom.
A race-day attendance of around 100,000 is expected on Sunday.
McLaren's Lewis Hamilton, who crashed in Friday practice, had described the conditions as way too slippery on Saturday morning.
"Guys, this is just unbelievable. Pretty much impossible to drive out here. There are rivers everywhere," the 2008 world champion, one of five contenders for this year's title, said over the team radio on one attempted lap.
Australian Mark Webber leads the championship for Red Bull, 11 points clear of Ferrari's Fernando Alonso with four races remaining.
Hamilton is third, 20 points adrift, with Red Bull's Sebastian Vettel one point behind and McLaren's Jenson Button fifth and 25 points off Webber.
"The crash yesterday did not help me," said Hamilton. "You need as many laps as you can get here and I have done about 15 laps this weekend but we have been driving all year so we should be okay."
Hamilton wins Belgian GP to take title lead
Webber puts Red Bull on pole in Belgium
Webber wins in Hungary to take F1 lead
Alonso holds off Vettel for Singapore win
McLaren reassure Hamilton over Monza mistake