AN ELECTRICAL storm knocked out a large section of the Western and Blue Mountains railway lines yesterday, delaying hundreds of passengers.

A lightning strike damaged signalling equipment and caused power outages between Blacktown and Penrith stations. Trains were unable to travel in either direction for about three hours.

CityRail replaced them with buses to Penrith and the Blue Mountains.

Passengers on the ground reported waiting at least an hour while drivers were found.

The storm also short-circuited several sets of traffic lights in western Sydney and flooded two lanes of Newbridge Road at Governor Macquarie Drive in Moorebank.

About 40 millimetres of rain was recorded at Merrylands West yesterday and flash flooding hit suburbs including Merrylands, Auburn and Picton, 80 kilometres south-west of Sydney.

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