A huge fig tree has been blown down by strong winds in central Sydney, injuring at least two people.

A large tree fell to the ground in Hyde Park around 3pm on Friday, crossing a sidewalk and landing on a busy street.

The first police officers on scene searched through a patch of branches and leaves to determine if anyone was trapped underneath.

Emergency services said no one appeared to be seriously injured in the incident.

A NSW Ambulance spokesman said two people with minor injuries were taken to nearby St Vincent's Hospital for treatment.

The tree on the edge of the park near St James' Station appeared to have split in two and crashed onto a nearby pavement.

According to a witness, the two were knocked to the ground by tree branches and bystanders ran to their rescue.

The man, who gave his name only as Chris, said he was walking along Elizabeth Street when he heard the tree crack and saw it hit a woman.

"A gust of wind blew and the tree fell," he said. "A woman is in the middle of it. If she had gone a few meters back or gone a few meters forward, the outcome would have been worse.

"But she walked away with a few scratches so she was really lucky. It was a high traffic area but luckily everyone got away."

Emergency services, including at least three ambulance crews, were called to the scene and police were diverting vehicles as the tree blocked both lanes of southbound traffic.

Police rescue crews are considering whether to chop the tree into pieces to clear the road.

Staff from the nearby Sheraton Hotel ran across the street to help the victims and search for others who were injured.

Onlookers were warned to stay away from other trees for fear they too would fall.

NSW SES spokesman Andrew Edwards said there had been 4,767 incidents in New South Wales since the severe weather began on Wednesday, with Sydney alone suffering severe damage and 2,130 rescues being called out. 600 of these incidents are still pending with the SES.

In Sydney, at least 20 trees fell on homes, at least 105 homes were damaged and 1,179 trees fell on roads and paths.

The Hunter region of New South Wales has also been severely affected, with at least 55,000 people in the region still affected by power outages.

—Krishani Dhanji contributed reporting