Round 16 of the 2015 Formula One World Championship is being held at Austin's Circuit of the Americas this weekend, but unfortunately the weather isn’t looking too good, with rain predicted for both Saturday and Sunday and even some stormy conditions possible. For Sunday’s race, there’s a strong chance of rain and the peak temperature is predicted to hit just 69 degrees F (21 degrees C).

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Team managers won’t have an easy task ahead of them as the weather in Austin this time of year can be quite changeable as well. This makes it difficult to get an ideal setup for cars. To keep things as flexible as possible, tire supplier Pirelli has nominated its versatile medium and soft compounds. The full wets will be ready, too.

Reigning world champion Lewis Hamilton, who won the United States Grand Prix last year, looks set to be awarded a third title this weekend. The Mercedes AMG man leads the Drivers’ Championship standings by 73 points and Ferrari’s Sebastian Vettel, who currently sits in second, has just received a ten-place grid penalty because of his team’s decision to use a fifth engine in preparation for next season.

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Going into the weekend, Hamilton has 302 points versus the 236 of Vettel and the 229 of fellow Mercedes driver Nico Rosberg. There are still four races and 100 points up for grabs this season. In the Constructors’ Championship, Mercedes has already received the 2015 title thanks to its unbeatable 531 points. Ferrari is second with 359 and Williams is a distant third with 220.

One driver to watch out for this weekend is American Alexander Rossi, racing for Marussia. He’s had just two race outings so far this season but on both occasions he beat his teammate. His appearance will be the first time since Scott Speed raced at Indianapolis back in 2007 that an American has raced in F1 on home soil.

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