Greg Swindells Chief Superintendent for the New South Wales State Emergency Services (NSW SES) said to be alert, not alarmed as widespread thunderstorms sweep across the state.

"Take extra care as you move around during the Christmas period. If you come across some dangerous conditions, if you're driving in areas you're not familiar with or even areas you are familiar with, if there is water across the road do not drive through it. Find another way. We want everyone to have a safe Christmas."

The thunderstorm warnings will not be contained to the Northern Rivers but extend north to the Queensland and south to the Victorian borders with minor flood warnings issued for areas of the south coast as the press conference was being held.

There is no suggestion of river flooding for the Northern Rivers at this stage, the warning is for flash flooding to occur if a supercell forms over particular locations.

Chief Superintendent Swindells said that in isolated areas we can expect between 100mm and 150mm from those supercells.

"To pinpoint an exact area is where the difficulty lays and we're liaising very closely with The Bureau. With the information that we have is early afternoon into the evening and late evening for Christmas Eve through to Boxing Day."

The warning from NSW SES is not only related to heavy rain and flash flooding but for potential large hail and strong winds."

"The risk for us also, as I've said, will be large hail, less than five centimetres in size and also strong winds.

"We've also reached out and spoken to Santa's Helpers in regards to some gifts that may be delivered overnight among strong winds. What we're asking Sanders helpers to do is to make sure that those items are secure around the yard for any winds when they pick up in the local area."

"Again, the message is for people as they travel around the state on roads. If they come across some water across the road for flash flooding to stop, turn around and find another way, don't drive, ride or walk through any flood waters and for people to make preparations around their house to secure any loose items that may become involved in heavy winds and be blown away."

The assuring news from Chief Superintendent Swindells was the planning and preparation that has gone into this weather situation.

"New South Wales SES are well prepared for the incoming weather during this Christmas period and have been preparing around the state since Friday in regards to the weather that we will see in the coming days."

(Chief Inspector Greg Swindells briefing the NSW SES team in the Goonellabah building)

"That planning involves our volunteer teams. Once again, being prepared to help the communities in New South Wales as and when required for storm-related work or for flash flooding in localised areas where work may be required to rescue people that may find themselves in some difficulty."

"We are also working closely not only with our own internal resources, but also working with our emergency service partners. We work closely with all emergency services including the Police Rescue Squad, Marine Rescue, Fire Rescue New South Wales Volunteer Rescue, and other agencies to support the communities in New South Wales. And once again, we have held significant meetings with those groups of people to assist the communities from this time."

"I'm confident we are well prepared, not only in the Northern Rivers but for the entire state of New South Wales."

"Listen to ABC radio which will give regular updates and also the Bureau of Meteorology and our website New South Wales SES."

Spare a thought for the staff and volunteers of the NSW SES. Some will be working today, tomorrow and Boxing Day with hundreds of volunteers on call should they be needed.

"Volunteers are wonderful people in the New South Wales State Emergency Service. They are people who live in their communities and serve their communities in times of need."

"Here in the Northern Rivers, we have standby teams for any activities that may occur and the 27 operational units that encompass my zone, the Northeastern Zone are ready to go on standby for any action that's required to assist their communities."

"What we ask is for people to help themselves in preparation to lessen the chance for volunteers or other emergency service partners will need to go out to do any rescues or to attend to any damage to their homes, for blocked gutters or anything similar to that."

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