Beijing's traffic authorities are preparing for the heavy traffic congestion that's expected ahead of and during the National Day holiday, which begins on Sunday.

Morning and evening rush hours from Wednesday to Saturday will see increased traffic, particularly on major routes in the city's northern, western and eastern areas, according to the capital's traffic management bureau.

Congestion will also extend to noncommuting periods, it warned.

The city's traffic performance index, which measures congestion on a scale of zero (smooth) to 10 (snarled), was expected to reach 8.5 on Wednesday, Thursday and Friday.

There were no precise data available for Saturday, the last working day before the holiday, although the bureau has said it will be the busiest day.

Restrictions on private cars based on the last digit of a vehicle's license plate will be lifted, starting Saturday, until Oct 8, the last day of the so-called Golden Week.

Roads near to commercial areas, wholesale markets and transportation hubs will bear the heaviest traffic, the bureau said, adding that it will closely monitor the weather and traffic flow to prevent gridlock.

Additional bus and subway services will help ease traffic peaks, with services also running later in areas with intense passenger flows, such as commercial and entertainment zones, tourist spots and transportation hubs.

Alerts and information on road conditions and suggested alternative routes will be broadcast on TV news programs, posted on signboards along main roads and shared via new media platforms, including Sina Weibo and WeChat, the bureau said.

Cheng Si contributed to this story.