St George flood peak revised down

The flood peak in the southwest Queensland town of St George has been revised down, raising hopes the community will escape a major disaster.

Nationals Senate Leader Barnaby Joyce says the Balonne River, which has already hit record levels in St George, is now expected to peak below the predicted 15 metres.

"They don't think it'll go to 15 metres," Senator Joyce told AAP.

"Below fourteen and a half is where they think it's going to be, which is good because that's below the level of the levee."

Senator Joyce was entering an emergency meeting which began in St George at 10am (AEST).

"We hope it's going to be lower. We'll just wait and see - wait and see and sandbag, there's not a lot more to be done at the moment."

A mandatory evacuation order was issued for St George after Premier Anna Bligh and Mayor Donna Stewart met local disaster management groups on Sunday.

Bureau of Meteorology hydrologist Chris Leahy said the possibility of a 15-metre peak at St George was now considered remote.

"The peak forecast hasn't exactly been revised down," he told AAP.

"We were working on a contingency plan of 15 metres but that level is looking fairly unlikely - it's not going to reach 15m.

"We were always saying it would go above 14 metres and that's still definitely on the cards - it's above 13.5 now and it'll keep rising today and tomorrow."

Mr Leahy said the levee bank at St George was 14.5m, which should be enough to hold the waters back.

"It's not out of the question it'll go above the 14.5 level but it's more likely not to."

He said the level should peak on Tuesday and remain fairly high for the rest of the week, before starting to drop slightly on Thursday and Friday.

"It's rising at about 2cm an hour at the moment and we'll see some quite large floods downstream from St George over the next week or so."

Mr Leahy said Dirranbandi will be the next town downstream to come under threat.

The water has reached 5.2m at Dirranbandi and is expected to reach 5.4m by the end of the week.

"From there it breaks out into quite a number of channels and starts spreading out.

"There'll be large rural areas flooded and people will be cut off for quite some time."