The Circuit de Catalunya near Barcelona, home of the Formula One Spanish Grand Prix, is a track all the teams know intimately and one where conditions can change significantly throughout the race, mainly due to the weather. The latest forecast for Sunday’s race is partly cloudy skies and a peak temperature of 79 degrees F (26 degrees C).

The wind direction is expected to be a southerly, which should remain light. However, as we’ve seen in previous years, changing wind direction is a common occurrence at the Circuit de Catalunya and often catches drivers by surprise.

The track is also one of the hardest on tires. The surface is quite abrasive but the main thing is all the fast corners that drivers accelerate through, which take a lot out of the rear tires in particular. Tire supplier Pirelli has nominated its two hardest compounds of the season: Orange Hard and White Medium.

After the first practice session earlier today, Mercedes AMG's Lewis Hamilton proved quickest, just edging out McLaren’s Jenson Button. Third quickest was Red Bull Racing’s Daniel Ricciardo followed by local favorite Fernando Alonso of Ferrari and then Mercedes AMG’s other driver Nico Rosberg. Many teams have implemented some upgrades for the Spanish race and so far it appears the Mercedes drivers don’t have the same advantage they enjoyed in earlier races.

One mishap was some failed electronics in a new chassis being used by reigning world champion Sebastian Vettel. This caused his car to stop after just four laps.

Going into tomorrow’s qualifying session and Sunday’s eventual race, Nico Rosberg leads the Drivers’ Championship with 79 points, with Lewis Hamilton just 4 points behind in second. Fernando Alonso sits in third with 41 points. In the Constructors’ Championship, Mercedes AMG leads with 154 points followed by Red Bull Racing on 57 and Force India on 54.

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