Get the brolly: Hail, winds, rain set to hit NSW

Hail has fallen on Newcastle and severe thunderstorms are likely to hammer parts of NSW with damaging winds and heavy rainfall.

The storms could also cause flash flooding in areas around Newcastle, Gosford, Armidale, Tamworth, Moree, Narrabri, Dubbo, Parkes and Wagga Wagga, the Bureau of Meteorology said in a severe thunderstorm warning issued this afternoon.

Almost 43 millimetres of rain has fallen on Newcastle and two centimetres of hail has hit the city's Bar Beach.

In Dubbo about 2.5 cm of hail came down.

The storms, which are moving towards the east to southeast from Newcastle, have prompted the SES to remind people to avoid from fallen power lines and bodies of water.

It also advises people to grab their pets, stay indoors, unplug computers and appliances and stay away from windows.

The BOM is predicting the foul weather to return to NSW tomorrow, with showers likely everywhere except the state's north.

It expects temperatures ranging from the mid-20s down to as low as 12 degrees, the forecast minimum for Camden in Sydney's southwest.

The temperature is due to dip to 7 degrees in parts of the Southern Tablelands.

An update is expected from the BOM later this evening.