Police believe too much sunshine could be contributing to the violent road rage incidents caught on camera in New South Wales this week.

The explanation comes as footage emerged of a peak-hour brawl erupting in Sydney’s west — the second road rage attack to be filmed in as many days.

In the mobile phone vision, four men can be seen getting out of their cars and throwing punches in the middle of a busy road in Merrylands.

As the fight intensifies, one of the men kicks another.

Merrylands Road Rage: Violent brawl filmed at the corner of Centenary Drive & Douglas Street yesterday. @jessdietrich7 #Merrylands #7News pic.twitter.com/eNWo3cTB1e

— 7NEWS Sydney (@7NewsSydney) July 25, 2017

Meanwhile, police on the Central Coast are still investigating after a woman was punched in the face after apparently throwing nails at another car.

Chief Inspector Phil Brooks, one of the state’s top traffic cops, said weather could be a factor in the attacks.

“It’s a combination of a number of factors but primarily on the days that they’ve occurred these are days of perfect driving conditions,” he said.

“Bright, sunny weather means more people on our roads… and quite obviously they’re taking these driving conditions for granted.

“People are wanting to get to their destination quickly. They’re very upset with a vehicle in front or alongside for whatever reason, and it’s them trying to bully other drivers in the hope that they can get ahead of the traffic queue.

“When there are different driving conditions, incredibly cold weather, raining and so on there’s less likelihood of these events occurring.”

Smartphones and dash cams have made filming road rage easier.

“People are generally reluctant to [hand footage to police], however we need them to commit to help us drive down the road toll on NSW roads,” Chief Inspector Brooks said.

“Whilst it’s fine to put it on social media… the primary mission for all road users that record these events either on dash cam or on their phone is to present that evidence at the nearest police station and commit to a statement.”

– ABC