Sydney Metro and trains affected as thunderstorm causes damaging winds, rain and hail

Commuters have been hit with peak-hour transport problems as a severe thunderstorm rolled through Sydney, bringing damaging winds and rainfall.

There were major delays as both trains and the Sydney Metro experienced outages across the evening.

Emergency services responded to hundreds of calls for help as winds downed trees and power lines and damaged roofs.

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The Bureau of Meteorology warned just before 6pm that a severe thunderstorm was on its way through Sutherland, Richmond and Liverpool.

The system moved east through Hornsby, Parramatta, Sydney City, Sydney Airport, Mona Vale, Sydney Olympic Park, the Sydney Harbour Bridge and waters off Bondi Beach.

Parts of Bradbury and Rosemeadow were pelted by hail this afternoon and gusts of 76km/h were recorded in Richmond after 5pm.

A power supply issue on the Sydney Metro North West and Bankstown line caused significant problems earlier in the night, stopping services between Barangaroo and Victoria Cross.

A Sydney Metro spokesperson said the fault was identified at 6.20pm, leaving services between Crows Nest and Sydenham at a stand on platforms with doors open to allow passengers off.

"Sydney Metro's operational control centre is monitoring all impacted services and customers on board trains via CCTV," it said, in a statement.

"Technicians are currently working to resolve the issue and resume services as quickly as possible. 

"We apologise to passengers for the disruption and thank them for their patience while we worked urgently to restore services."

Power was restored just after 7pm but passengers were advised to allow extra travel time.

The train network was also badly affected.

Just after 7pm, authorities confirmed no trains were running between Gordon and North Sydney on the North Shore line.

They blamed "severe weather conditions affecting infrastructure" and said replacement buses were not available.

Travellers on the Western line were urged to allow extra travel time because trains could stop on platforms or between stations for longer than usual.

There were delays on the T1 Western, T2 Leppington and Inner West, T3 Liverpool and Inner West and T5 Cumberland lines.

Firefighters responded to more than 250 calls for help, mostly for downed trees and power lines.

The SES responded to 269 incidents across the state since 5pm, with 200 just in Sydney

Most of the jobs involved downed trees and branches as well as damaged roofs.

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