"It looks like world wheat plantings will rise by 2 to 2.5 per cent on last year," he said.
"A large part of that crop is already in. Northern hemisphere winter wheat makes up the bulk of global wheat production and it's already planted. While there have been a few weather problems, it's still early days."
It would not be until March or April, when there would be a better idea of the northern hemisphere crop size, that prices could start to move significantly.
"With more crops planted, even with just a reasonable year and reasonable yields, prices will come down," he said.
Mr George said grain prices should remain high in the first few months of 2013, but consistent strong returns depended on adverse weather conditions in one of the world's major graingrowing areas.
"Without any major weather problems through the world, it's reasonable to expect prices will be coming down," he said.
On the back of very strong grain prices in 2012, the United States had planted a record corn area and South America a substantial corn area. But weather risks were looming.
"The US had that incredible dry spell and drought that devastated crops in 2012 and those conditions haven't completely finished," he said.
"Soil moisture is critically dry in the US. They're hoping there will be a huge amount of snow in the winter, so in the spring there's some subsoil moisture."
Mr George said it would be unrealistic for farmers to expect similar prices next season.
"If you're banking on prices similar to this year, you've got to bank on weather problems," he said.
Profarmer editor and analyst Malcolm Bartholomaeus said there was every possibility wheat prices leading up to the Australian harvest in 2013 could be between $210 and $220, delivered to port.
