Beijing cool for men's 50km walk

BEIJING (Reuters) - Olympic host city Beijing was cool on Friday after a day of heavy rain, with the sun trying to break through a morning mist as the men set off from the Bird's Nest stadium on their 50km walk.

The Beijing Meteorological Bureau (www.bjmb.gov.cn) forecast a high of 31 degrees Celsius (88 degrees Fahrenheit) and a low of 18 Celsius, with a small threat of thunderstorms.

The grey skies would give way to sunshine later in the day, the bureau said.

Air quality would be Grade 1, the best rating by Chinese standards, boding well for athletes competing on the track and field and other outdoor venues.

Jamaica's Usain Bolt could run away with a third gold on Friday to complete the Caribbean island's dominance of the Olympic athletics track.

The dazzling double gold winner and world record holder will race in the 4x100 meters relay. Jamaica's Veronica Campbell-Brown, who won the 200 meters on Thursday to rout the United States, will help to defend the team gold she won in the women's sprint relay in Athens.

A typhoon was headed for Hong Kong and expected to make landfall in the afternoon or in the evening, but equestrian events finished in the city on Thursday.

(Reporting by Guo Shipeng; Editing by Nick Macfie)