Large hailstones hit houses and cars as well as a sudden downpour.
The ceiling at the entrance to the Penrith HomeCo Center collapsed due to the storm. No one was hurt.
The entire store was evacuated after the roof collapsed and the center began to flood.
There are now significant traffic delays on the Anzac Bridge after heavy rains caused flash floods.
Two of the three westbound lanes are currently closed.
Motorists are urged to be careful when driving near flood waters.
The Bureau of Meteorology (BoM) said severe thunderstorms no longer affect Greater Sydney.
“The immediate threat of severe thunderstorms has passed, but the situation will continue to be monitored and further warnings will be issued if necessary,” the BoM said in a statement.
A severe weather warning is in place for the state’s north coast, Hunter, Metropolitan, Central Tablelands and Central West, however.
These thunderstorms are likely to bring heavy precipitation and flash floods tonight.
“The sites likely to be affected are Taree, Gosford, Scone, Mudgee, Wellington and Hill End,” the BoM said.
Weatherzone said more than 130,000 lightning bolts erupted over New South Wales today as the trough moves across the state.
“A few systems, notably near Penrith, Gosford and Karuah, have brought hail,” said Joel Pippard of Weatherzone.
“In addition, heavy rains of 24.8mm in 30 minutes at Chifley Dam and destructive winds like 83 km / h at Gunnedah were recorded.”
The storm will subside overnight but is expected to start again in the morning.
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