Fernando Alonso lead the chase of Mercedes at Silverstone on Friday as the Spaniard took third spot in both sessions.
Lewis Hamilton led the way in the second practice session ahead of teammate Nico Rosberg, with third-place Alonso 0.736 seconds off the pace.
"There were no problems with wear or graining on the softer compound," said Alonso. "While in order to correctly evaluate the hard [tire], we will have to wait for a long run test. For now, I can say it's hard to get them up to temperature.
"Now, as usual, we must analyze everything to understand which components to use tomorrow, although if as predicted, it rains tomorrow, then in reality the data we got today will be more useful for the race. Here, there's always a strong wind and in some corners it's a help, while in others it's a hindrance, but it's the same for everyone. Now, all we can do is wait and see how things turn out."
Ferrari teammate Kimi Raikkonen was less happy after encountering some handling problems, which was not helped by the windy conditions. Raikkonen finished the day down in 9th spot.
"At Silverstone, the weather is often unsettled and that can have a strong influence on the outcome of practice and the race," said technical director Pat Fry. "Therefore, it's vital for the drivers to do a lot of laps to get as confident as possible with the car. Today, despite a strong and inconsistent wind, we were able to work through our program without encountering any particular problems. On both cars, we tried some new aerodynamic components and various electronic settings, while on the power unit front we continued to acquire data useful for our development program.
"At the same time, we went through the usual setup tests to find the most suitable one for this track, as well as paying attention to tire behavior over short and long runs. It wasn't easy to find the ideal balance as well as managing the degradation and while Fernando managed to complete a long run, with Kimi, we continued working on setup to try and resolve some problems that cropped up on his car.
"Now we must find the best compromise to help both drivers to get the right stability for the rest of the weekend, taking into account that the weather is meant to get worse for tomorrow with a chance of rain."
