Source: Bureau of Meteorology

For people in parts of Sydney and Wollondilly/Wingecarribee areas.

Issued at 7:10 pm Wednesday, 24 November 2021.

The Bureau of Meteorology warns that, at 7:05 pm, very dangerous thunderstorms were detected on the weather radar near Blaxland and Warragamba. These thunderstorms are moving towards the south to southeast. Very dangerous thunderstorms are forecast to affect Camden, Cobbity and Oran Park by 7:35 pm and Campbelltown, Appin and Wedderburn by 8:05 pm.

Other severe thunderstorms were detected on the weather radar near Londonderry, Penrith and the St Georges Basin/Jervis Bay district (south of Nowra). They are forecast to affect Erskine Park, Rooty Hill and St Marys by 7:35 pm and Cecil Park, Horsley Park and Hoxton Park by 8:05 pm.

Intense rainfall that may lead to dangerous and life-threatening flash flooding is likely.
Warragamba has recorded 59mm in 1 hour.

The State Emergency Service advises that people should:
* 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.