The weather is often very changeable in the area surrounding the Spa-Francorchamps circuit, where the Formula One Belgian Grand Prix has been held since the sport’s inaugural season back in 1950. Because of this, races at Spa are rarely straightforward.

The current weather forecast for Sunday’s race is partially cloudy skies and a low chance of rain. The peak temperature is only expected to reach 55 degrees F (13 degrees C) and humidity will be a high 81 percent. While it looks like we could be in for a dry race, some rain fell overnight and more of the wet stuff is expected for tomorrow’s qualifying session.   

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One of the biggest headaches for teams is that the length of the Spa circuit, which stretches 4.35 miles and is the longest on the calendar, makes it difficult to select the optimal tires. It can be very wet on some parts of the circuit while it stays completely dry on others. Pirelli has nominated its P Zero White medium and P Zero Yellow soft tires, a softer combination compared to last year.

For American race fans, Marussia has confirmed that rookie Alexander Rossi will be making his F1 debut this weekend. The California native was only signed on as a reserve driver for the team in late July but will already sit in for current driver Max Chilton. In a statement, Marussia said Chilton was sitting out while “contractual issues are resolved.”

This will mark the first time that an American has competed in F1 since Scott Speed’s stint with Toro Rosso ended in 2007. Note, Caterham has also chosen to replace one of its drivers, Kamui Kobayashi. The Japanese driver will sit out for one race, with German Le Mans racer Andre Lotterer taking his seat.

Going into qualifying tomorrow and Sunday’s race, Mercedes AMG’s Nico Rosberg leads the 2014 Drivers’ Championship with 202 points, with his teammate Lewis Hamilton in second with 191 points and Red Bull Racing’s Daniel Ricciardo a distant third with 131 points. In the Constructors’ Championship, Mercedes AMG has 393 points versus the 219 points of Red Bull Racing and 142 points of Ferrari.

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