F1 Pirelli Austin GPFormula 1 teams will have an extra set of hard tires at their disposal for Friday practice for this weekend's United States Grand Prix.

Pirelli, which is taking the medium and hard tires to the Austin race, will give the teams the chance to get additional running and get familiarized with the new Circuit of The Americas, where Formula 1 will compete for the first time. Pirelli said the initial information for the 3.43-mile track suggests the surface will be quite smooth.

Motorsport boss Paul Hembery believes the Circuit of The Americas will be one of the biggest challenges for the tire manufacturer this year.

"Stepping into the unknown is a situation that we are used to: last season the majority of tracks were completely new to us," he said. "We've chosen the hard and the medium compounds as we think it will be quite a demanding track, based on the asphalt samples and simulation data we have gathered.

"Naturally, we've leaned toward a slightly more conservative choice in order to cover every possibility at a brand-new circuit, but the tire choice in Abu Dhabi was also conservative and yet we saw one of the most exciting races of the year."

The current weather forecast for the Austin area calls for near-perfect conditions for all three days, with partly cloudy conditions and temperatures in the low 70s.