Ahead of today's free practice session, the air temperature is 20 degrees C, whilst the track temperature is 27 degrees.

Whilst it was hot and dunny yesterday, strong winds caused problems for many already struggling for grip. Unfortunately, though cooler today, the winds persist.

Nico Rosberg was quickest in both of yesterday's session, despite missing much of FP1 with a hydraulics issue, and whilst teammate Lewis Hamilton kept him honest in FP1, in the second session the Briton, who complained his car was "all over the place", slipped to fourth. As in Austria, the world champion doesn't appear at one with his car.

Behind him were the Ferraris of Kimi Raikkonen and Sebastian Vettel though it was the Red Bulls and Toro Rossos that impressed.

Fact is however, it was Friday and therefore the teams were giving little away.

The B-spec Force India made an impressive debut, and hopefully we'll get a better idea of it as the weekend progresses.

The lights go green and Grosjean gets things underway, followed by Merhi.

As more and more drivers take to the track, Grosjean posts the first time of the day (37.395).

As sparks fly from underneath Hamilton's car, Raikkonen goes quickest with a 36.718.

Alonso goes second, just 0.005s off Raikkonen's pace, but there's a long, long way to go.

Massa runs very wide at T9 - Copse for those fellow oldies. Incidentally, drivers have been warned at running wide and gaining an advantage at certain corners - this being one of them - if they do so in qualifying they'll lose the time.

Ericsson complains that he has no info display on his steering wheel.

As Bottas goes quickest (35.082), ahead of his teammate, Verstappen runs wide in T9. Moments later Perez goes off through the kitty litter after getting it wrong at T3.

Though unhappy with his car, Vettel posts 35.627 to go third. Next time around, using all the track and then some in the final corner, he improves to second (35.364).

A 35.504 sees Hulkenberg go fourth, as the Mercedes and Red Bull duos remain the only drivers still to post times.

Vettel goes quickest (34.932) whilst Verstappen, having gone quickest in S2, crosses the line at 35.232 to go third.

Early days, but Alonso currently eighth and teammate Button twelfth.

Twenty minutes in and Rosberg follows the Red Bull duo down the pitlane. Hamilton duly heads out.

"I don't know why but T3 is always impossible," admits Verstappen as he is leapfrogged by teammate Sainz.

Asked if he wants to go for three hot laps or a cooling off lap in between, Rosberg replies: "Three!"

His first lap producing a 35.750, next time around Rosberg goes quickest in all three sectors, posting a 34.436, just 0.3s off yesterday's best (on options).

Moments later, Hamilton takes the top spot with a 34.399, bumping Kvyat (34.774) from second to third.

Rosberg re-takes the top spot with a 33.731, the quickest time of the weekend. However, going quickest in all three sectors, Hamilton responds with a 33.333. Third placed man, Raikkonen, is 1.261s off the pace.

On the half-hour, Button is the first to switch to options. Currently fourteenth on 36.002 he improves to 35.695 having lost time in S3.

Perez and Vettel are the latest drivers to have minor excursions at T9, Hulkenberg opting to follow their example.

"One of the big factors influencing lap time today is wind," confirms Pirelli, "it's warm but quite windy, which affects aerodynamics."

Problems for Nico? In the Mercedes garage the car is removed from his car amidst talk of a leak, with just 16 minutes remaining.

Asked if his balance is any better, Ricciardo responds: "No, I'm still struggling in the same areas."

As we await the big switch to options, it's: Hamilton, Rosberg, Raikkonen, Kvyat, Vettel, Verstappen, Ricciardo, Bottas, Sainz and Maldonado.