It's picked to be grim news for dairy farmers, ahead of Fonterra's new season opening forecast announcement.

The co-operative's board is meeting this week, against a backdrop of flagging global commodity prices.

ANZ Rural Economist Con Williams expects Fonterra to announce a range between five and $5.25 for the milk price, and an advance rate around the mid $3 mark.

"It's going to be pretty tight for farmers through 15/16 season to balance their books."

KPMG's Brent Love told Newstalk ZB farmers are realistic and they're not expecting much, but if the number's below five it will put a lot of pressure on them.

"I think dairy farmers at the moment are just looking to get that over with, get a number, get an idea, get a plan and get on with the first half of the 2015/2016 season."

Con Williams says given the challenges the sector's facing right now, he wants Fonterra to give farmers monthly price updates, rather than quarterly.