The SES responded to 130 incidents, with Lithgow, Moss Vale and Mount Druitt among the worst-hit centres.
A total of 16 flood warnings remain in place across the state.
Major flooding is taking place on the Namoi, Macquarie, Bogan and Lachlan rivers.
In Sydney, drivers were forced to pull off the road this morning due to the intensity of the rain, accompanied as it was by lightning and thunder.
It follows intense hail in the city’s west yesterday, blanketing Penrith, Springwood and Mount Druitt.
Similar conditions are expected throughout today across the state.
South-east Queensland has also been hammered by severe thunderstorms and is facing potential flash flooding.
Residents in at-risk communities have been put on high alert for coming days.
The wet weather is expected to last right up until later next week.
Drivers find themselves trapped in floodwaters as heavy rain hits two states
