Shopping centre roof caves in during wild Sydney storm

A worker at a Penrith shopping centre has captured the terrifying moment the roof collapsed amid heavy rain in Sydney on Tuesday afternoon.

The footage shows the heavy rain outside before panning over as the roof caves in, with shoppers running out of the way.

Outside, rain is steadily falling, with huge puddles forming.

It comes as the Bureau of Meteorology (BOM) warned of severe thunderstorms across the eastern half of NSW.

A worker in the centre, Georgia Davis, told 7News she was filming the rain pooling at the entrance of the centre when disaster struck.

“I was just filming all the water that was coming in through the entrance when all of a sudden the roof collapsed," she said.

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“We then all had to leave through the emergency exit, and we got a text message from our boss saying the entire centre had been evacuated.”

Sydneysiders react to storms

Sydneysiders shared photos from the storm online, some unable to leave their homes due to flooded roads.

"One of our staff members captured these pics in #SouthPenrith of the #Sydneystorm this arvo, her road was #flooded & almost cut off within 10 mins!" one Twitter user wrote.

"A timely reminder to know your #flood plan & prepare for your #animals & #livestock."

Another video showed rain relentlessly pouring down in Leichhardt, in Sydney's inner west.

Conditions could worsen during the week

BOM said the rain is likely to continue across much of eastern and inland NSW from now until Friday.

"Heaviest falls are likely in southeast NSW on Thursday, where the low-pressure system develops," an update read.

"Flooding continues and extra rain means renewed flooding is likely."

Isolated severe thunderstorms are possible across the eastern half of NSW on Tuesday, with the potential for localised heavy rain, large hail and damaging wind gusts.

Conditions will worsen during the week, with strong coastal winds and hazardous surf also possible, most likely for the Hunter coast and south.

BOM manager Agata Imielska is most concerned about the potential for more flooding.

"Our catchments are very sensitive after the very wet — record wet — November and broadly wet conditions during spring," Ms Imielska said.

"We do have the risk of riverine flooding but also flash flooding associated with any heavy localised rainfall.

"It's very important for the broad community to keep a close eye on warnings and radar to monitor those conditions."

with AAP.

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