Hail, wind, rain hit NSW during wild thunderstorms

Hailstorms, winds and heavy rain have slammed parts of New South Wales after a storm front swept across the state.

Lightning blasts the ground near Blacktown in western Sydney, Nick Moir tweeted. (Twitter @nampix)

Thunderstorms have hit parts of NSW, bringing hailstorms, winds, heavy rain and lightning.

The Bureau of Meteorology had issued a warning for Sydney, the Illawarra, Hunter, mid-north coast and upper western and northern tablelands, but has since issued an update, saying the immediate threat had passed.

The NSW State Emergency Service said they've responded to more than 70 calls for help, with the majority of calls from the Penrith and Mt Druitt areas.

A woman was reportedly struck by lightning outside a school in Oran Park. Fairfax Media reports the woman is believed to have suffered mild burns after lightning struck her umbrella.

Lightning strikes also affected public transport with train signals knocked out on the Western Sydney train lines.

The storm also affected flights arriving and departing from Sydney Airport.

Around 17,000 homes lost power in Sydney's west during the storm.

For emergency help in floods and storms, ring the SES (NSW and ACT) on 132 500.

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