Traffic jams expected around Sonoma Raceway for IndyCar finale

Motorists are advised to avoid the roads near Sonoma Raceway this weekend.

The track is hosting the GoPro Grand Prix, which kicked off Friday. The heaviest traffic is expected Sunday, when the season finale of the Verizon IndyCar Series is held. Unlike the cars that will be zooming around the track, traffic is expected to come to a crawl along the roads leading to the raceway off Highways 121 and 37 south of Sonoma.

Motorists are urged to find alternative routes. Raceway officials expect to see the heaviest congestion from 9 a.m. to 2 p.m. and 5 to 8 p.m. Sunday.

Race fans should arrive early to avoid traffic jams, officials said. The raceway will have 30 CHP and Caltrans workers at the event to help with traffic. To ease congestion, the raceway is also adding its Raceway Fun Train to the IndyCar race for the first time. The train, which has been used at the popular NASCAR Sprint Cup Series since 2013, will bring fans from Sacramento, Davis and Suisun.

Meanwhile, the raceway has posted dozens of changeable message signs within a 15-mile radius around the track, encouraging non-race travelers to stay away from Highways 37 and 121. A study by the raceway found that 85 percent of motorists traveling those two highways during peak race entry and exit times were not attending the event.