Hailstones up to 3cm in diameter were recorded in Merewether.
© Julian EllisHailstones up to 3cm in diameter were recorded in Merewether.
A major regional city has been pounded by hailstones as an intense storm struck, leaving thousands without power and hundreds needing SES help.

Newcastle was in the firing line for some of the worst of the storm, with large hail stones raining down over the city's centre and suburbs including Merewether, The Junction, Bar Beach and Cooks Hill.

NSW SES received an influx of calls during the storm, with 420 incidents reported.

"Over the span of 15 minutes alone, we received 45 jobs for hail and roof damage, with an additional 40 jobs waiting in the queue," the SES said.



Volunteers are working through the evening on the highest priority jobs, with all 756 calls expected to be answered by Saturday afternoon.

The majority of calls for help were for hail and roof or sky light damage.

Authorities are also warning people to not enter floodwater or go near fallen power lines.

Around 2100 homes initially lost power in Newcastle as a result of the storm, however most have been brought back online.

"We have no power, no lights, no internet no nothing. Can't even wash our lunch dishes because I can't see," one resident said on social media shortly after the storm.

SES Hunter duty officer Neil Wildin said he was "glad the storm didn't happen in a larger metropolitan area" as damage could have been much worse.

The small but "intense" storm formed near Gosford on the Central Coast at about 10.30am on Friday and continued to pick up strength as it barrelled up the coast, producing heavy rain and hail by the time it reached Wyong at 11am, WeatherZone Meteorologist Ben Domesino said.

"The thunderstorms formed near a southerly change that swept up the NSW coast on Friday, causing cold air to undercut warmer air, forcing the warm air to rise and produce storms," he said.

The suburb of Merewhether was inundated with 56mm of rain in just an hour.

The hail and heavy rain were also accompanied by "copious" amounts of lightning.

Residents have been shocked by the ferocity of the storm.

"Never experienced anything like this," Newcastle local David Diehm said.

"The hail is relentless!"

Some reported hailstones with a 3cm diameter.

The hailstorm is not the only piece of severe weather hitting NSW on Friday, with snow also falling across parts of the state.

"Snow will settle in parts of Tas, Vic, NSW and the ACT from Thursday into Friday, possibly reaching into parts of northern NSW," Mr Domensino said.

"This will include a decent fall in the mainland alps, helping to create a snow base for the upcoming ski season."

Perisher received 15cm of snow across Thursday and Friday according to SnoWatch.

A cold front and its mass of air produced a wintry mix of low temperatures, rain, snow, hail and strong winds, with the BOM saying that wind speed in Sydney reached 30km/h on Friday.

The storm has now passed through the Newcastle area and is heading north through Port Macquarie and the Hunter Coast.

"Storms will continue to move further north into Friday afternoon as the southerly change continues to make its way up the NSW coast," Mr Domesino said.

The BOM has issued a general storm warning for these areas.