Westfield Bondi Junction has been evacuated because of heavy rainfall and flooding.
A second storm is currently ripping through Bondi in Sydney's east.
Kurnell is experiencing the highest wind speeds in Sydney's history at 213km an hour, reports ABC weatherman Graham Creed.
The Bureau of Meteorology has released another severe thunderstorm warning for Kiama, Shellharbour, Dee Why, and the northwest parts of Wollondilly Shire.
The Bureau of Meteorology has sent out a severe thunderstorm warning - including possible tornado - for large parts of Sydney.
It is predicted the storm will travel from Kurnell and hit areas in Bondi, Sydney CBD, and the northern beaches.
The State Emergency Service advises that people should:
* Move your car under cover or away from trees.
* Secure or put away loose items around your house, yard and balcony.
* Keep clear of fallen power lines.
* Keep clear of creeks and storm drains.
* Don't walk, ride your bike or drive through flood water.
* If you are trapped by flash flooding, seek refuge in the highest available place and ring 000 if you need rescue.
* Unplug computers and appliances.
* Avoid using the phone during the storm.
* Stay indoors away from windows, and keep children and pets indoors as well.
* For emergency help in floods and storms, ring the SES (NSW and ACT) on 132 500.
Brad Esposito is a news reporter for BuzzFeed and is based in Sydney, Australia.
Contact Brad Esposito at firstname.lastname@example.org.
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