Ahead of today's sole practice session the air temperature is 12 degrees C, whilst the track temperature is 26 degrees. It is cool, to say the least, but bright, though also somewhat windy.

Lewis Hamilton was quickest in both of yesterday's session, though in FP2 he somewhat blotted his copybook. Just two weeks after the strategic error that saw him gift an almost guaranteed win to teammate Nico Rosberg, the team once again had its judgement called in to question when it opted to send out both drivers in the pouring rain on Inters.

At a time the rest of the field elected to wait and see how the weather developed, Mercedes opted to send out both drivers. Whilst the move might have been appreciated by the fans, it was to prove costly and embarrassing, for halfway around the circuit Hamilton slithered off into the barriers.

Thankfully it was the team's (and its driver's) pride that took the biggest battering, though once again the question everyone was asking was, why?

Before the rain, despite Hamilton having been quickest, it was the Ferraris that looked best, the red cars, with their upgraded engines, seeming, once again, to get the best out of their tyres in the warmer conditions.

Williams was looking good also, prompting one to wonder whether, on this circuit that always produces surprises, could we be on the verge of witnessing Valtteri Bottas' maiden win.

Lotus was also up there, Pastor Maldonado posting the fifth best time of the day.

With the rain looing to have gone for the weekend - but never take anything for granted here - attention will be on grunt and brakes, and whilst Mercedes has plenty of the former we know that the latter has often proved to be an Achilles heel for the German cars.

Tyre compounds are the same as in Monaco, soft (prime) and supersoft (option), and whilst the options are good for a few fast laps it was noticeable yesterday how hard drivers were having to work in order to generate heat into them. That said, all will be hoping the temperature rises noticeably over the next hour.

There are two DRS zones, the first on the straight leading to the final chicane and the second on the pit straight leading to T1. They share a single detection point located just before T9.

We saw a numbers of offs and spins, Hamilton completing a 180 at T10 - scene of his FP2 faux pas - earlier in the day, right in front of his teammate.

Like Ferrari, Honda has upgraded its engine however, Jenson Button was thwarted, particularly in FP1, by a gearbox issue.

With more than half of yesterday's second session washed-out, the drivers will have much to do this morning as they prepare for qualifying.

Sadly, Max Verstappen, who already faces a 5-place penalty for the incident in Monaco, looks likely to take the first (10-place) engine penalty of the year, the Dutch teenager being the first driver to use a fifth unit. There's an engine change for Alonso also, but it's only his fourth of the season so no penalty.

The lights go green and Maldonado leads the way, Bernie Ecclestone, standing in the pitlane talking to a guest, clearly riding his luck. Ricciardo is another early riser, as are Merhi and Grosjean.

Ricciardo posts the first time of the day (1:24.212) before running wide in T1.

Raikkonen raises the bar with a 20.409, the Finn using all his guile to keep his distance from the Wall of Champions. Elsewhere, Vettel reports that the track is "very dirty".

As Ricciardo improves to 20.602, the cameras pick up on clouds of brake dust billowing from the rear of Button's McLaren.

As Raikkonen improves to 18.521, teammate Vettel goes second with a 20.062 before improving to 19.653.

Ten minutes in and as Ricciardo splits the Ferraris, all but Alonso and the Mercedes have been out.

Verstappen goes fourth (19.960), ahead of Button, Perez and Sainz, as Vettel misses the final chicane and is force to use the new detour, his Ferrari launched into the air by the kerbing.

An 18.829 sees Kvyat go second as Raikkonen consolidates his top spot with a 17.879.

Hulkenberg goes fourth (19.595) but is soon demoted when Vettel bangs in a 17.543.

Raikkonen pits having admitted that on his previous lap he ran wide in T7 and went on to the grass.

As Kvyat looks set to improve, Perez and Hulkenberg are third and fourth for Force India. Sure enough, Kvyat posts a 17.953 to go third.

Nasr gets frighteningly close to 'the wall', as Sainz is advised the procedure should he get it wrong in the final corner. Moments later, teammate Verstappen misses that very corner.

"Those who miss the corner entirely have to stay left and rejoin after the polystyrene marker," Sainz is told. "This is important."

Eighteen minutes in and Rosberg finally leaves his garage. Still no sign of Hamilton or Alonso.