A night of severe thunderstorms has firefighters waiting to see if numerous lightning strikes have sparked more bushfires across the state.

“Not exactly what we wanted to see,” the NSW Rural Fire Service tweeted after the state was hit by a number of storms on Monday evening.

The Bureau of Meteorology tweeted a warning that severe thunderstorms were moving through the Newcastle and Port Stephens regions and are also expected to hit the Blue Mountains.

The BOM said while storms in the Sydney, Wollongong and Maitland areas had eased “the redevelopment of severe thunderstorms remains likely”.

The RFS will investigate whether the evening’s storms sparked more fires, after aircraft spent the day searching for new bushfires sparked by thunderstorms on Sunday night.

There were 80 fires burning across the state at 7pm on Monday, with 50 of them uncontained.

Earlier in the day, the RFS revealed while its building impact assessment teams are still assessing fire-affected areas across the state, so far 663 homes had been destroyed.