Wet weather created a frenetic Turkish GP in 2020, and forecasters have given a 30-40% chance of a repeat of those conditions on Sunday.
The wind is set to be a factor throughout the weekend, which could add potential issues as the drivers try to negotiate a track with plenty of medium and high-speed corners.
Dry weather is expected on Friday, with the potential for rain overnight heading into Saturday morning, although any wet weather should have cleared up by the time qualifying comes around.
The BBC predict that cloud cover will be variable on Sunday, and there is uncertainty surrounding how much rain, if any, will present itself at Istanbul Park when the lights go out on Sunday.
Rain played its part on a slick, resurfaced track in 2020 in qualifying and the race, but FIA race director Michael Masi confirmed that the whole circuit has been treated by being water-blasted, in the hope of adding grip this time around.
#F1 #BBCF1 #TURKISHGP: Dry & breezy sessions FRI, with increasing scope for light-moderate showers/rain developing overnight-SAT am. Risk of showers likely reducing through the day (40%). SUN variable cloud; brisk NE breeze; shower risk currently rather uncertain (30-40%). 20-22C pic.twitter.com/gMM0vg3oZO
— Ian Fergusson (@fergieweather) October 6, 2021
The FIA also confirmed that track limits infringements at three separate corners will result in lap time deletions over the course of the weekend, as well as black-and-white flags set to be shown for drivers who break the limits three times or more.
Turns 1, 6 and 14 will all be under the microscope as drivers try to set their fastest lap times, and the kerbs will be strictly policed in case they gain an advantage by heading off track.
The plunge downhill on the exit of Turn 1 is a tricky challenge for the drivers, as they look to gain a strong start to the lap. Likewise at the left-hand kink at Turn 6, which is taken at full throttle, drivers will need to be careful to keep their cars within the limits of the kerbs.
There will be a double-dose of pain if a driver goes too far off-line at Turn 14, the final corner at Istanbul Park, as not only will their current lap time be deleted, the following lap will also be invalidated – adding to the need for caution as they put the power down.
As well as the track limit rules, a bollard and speed bump have been installed at Turn 9, just after the DRS detection point on the far side of the track.
This left-right chicane sets up the longest period of acceleration on the track, so the FIA acted to stop drivers from gaining further advantage by straight-lining that section.