During a heatwave throughout Europe, temperatures at Hockenheim were among the highest ever seen, peaking at 58 degrees centigrade track temperature, with more than 40 degrees ambient.
These very high temperatures enhanced thermal degradation on the tyres: however the fastest times were still set on the soft compound in FP2.
As usual, there was a high degree of track evolution, but the situation improved in FP2 with more rubber laid down. The afternoon session was interrupted by a red flag with 15 minutes to go.
Ferrari was fastest in both sessions today, but it's unclear how representative today's conditions will be - as the weather for the rest of the weekend is expected to be cooler, with a risk of rain.
Despite the punishing conditions, even the softest compounds stood up well to the extreme temperatures, combining both performance and durability during all the qualifying and race simulations.
All three compounds were used extensively today and all are likely to figure prominently in the race. There's currently a performance gap of around 0.6 seconds between soft and medium, with a slightly smaller gap between medium and hard.
Mario Isola: "There's currently a performance gap of around 0.6 seconds between soft and medium, with a slightly smaller gap between medium and hard. The overriding characteristic of today was intense heat, with track temperatures well in excess of 55 degrees centigrade, which were among the highest we have ever seen in Formula 1. This meant that the drivers had to look after the rear tyres in particular, but in spite of the extreme heat, all three compounds coped well with the conditions: even the soft, which set fastest time today. All three compounds look well-suited to the track and the current conditions, but it's hard to know exactly how the weather will evolve over the rest of the weekend - with some rain expected from tomorrow. If that's the case, as happened last year too, then it will lend yet another interesting element to a weekend that's already proving quite hard to predict, with close gaps among the frontrunners."
Check out our Friday gallery from Hockenheim, here.