Saturday’s US timetable could be adjusted to deal with the continuing bad weather, sources have confirmed.
At the moment it’s believed that the worst of the weather will pass through later in the day, so the FIA is considering moving the schedule forward. The call will be made based on the best available information at 0700 tomorrow.
The problem with bringing FP3 forward from its current 1000 start to 0900 is that it would eat into the time the teams have after the end of the overnight curfew, and some may not have enough tome to complete their usual workloads.
However even if FP3 does not move it would be possible to shorten the lunch break and run qualifying an hour earlier, moving it from 1300 to 1200.
If there is no qualifying at all – even on Sunday morning – then the grid will probably be based on FP3, as the rules state that if drivers don’t set quaifying times then FP3 is taken into account.
If there is no more track running at all prior to the race then the Stewards have options. They could use championship positions or FP1 to set a grid.
Adam Cooper's F1 Blog 