Last month, Fonterra held its forecast at $6, but that is expected to slide further, probably when the dairy giant announces its annual results on Wednesday.
While ASB and Westpac have both downgraded their forecasts to $5.30, ANZ saw prices around the mid-$4 mark.
Earlier this year, bumper global production and softer demand in China were driving down prices.
Now, the effects of the Russian import ban and weaker Russian dairy demand are compounding those factors.
Dairy farmers would be ''partially insulated'' from the effects of a sharply lower payout by retrospective payments from the record-breaking 2013-14 season, Westpac senior economist Anne Boniface said.
But while one tight year was likely to be manageable for most, the outlook for 2014-15 became very important.
At this stage, Westpac was still comfortable with its forecast of a $6.60 milk price payout in 2015-16, she said.
Another factor important for farm cash flows was Fonterra's advance payment rates.
Fonterra left those unchanged when it downgraded its 2014-15 season payout forecast to $6 in late July.
But with $6 now looking ''pretty optimistic'', the co-operative might look to tweak those, she said.
Asked what his predictions were for the 2014-15 milk price, Federated Farmers dairy chairman Andrew Hoggard said he left those up to the market analysts. However, what he was hearing a lot of was in the mid-$5 range.
''All we say to farmers [is] it's a volatile season. Just be prudent and conservative with your budgets,'' he said.
While it was a short-term hit, the medium-term outlook was positive and long-term it was even more positive, he said.
While farmers were ''nervous, to a degree'' as to where the payout might go, most were focusing on things they could influence, such as pasture rotation, animal health and milk in the vat.
''We don't have influence over the international marketplace. We have influence over what happens on farms.''
The price index was unchanged in this week's auction.
Milk powders posted modest gains, with whole milk powder and skim milk powder up 0.6% and 0.9% respectively.
Casein was up 1.3%.
Anhydrous milk fat, butter and cheddar all posted falls of about 2% and butter milk powder fell nearly 7%.
Overall, prices stood 42.4% lower than a year ago.
But Mr Hoggard described the auction result as welcome news for dairy farmers.
''With peak milk about four weeks away, we could do with some good news and, while steady as she goes isn't a plus sign, at least it is not a negative,'' he said.
While recent falls in the New Zealand dollar were ''helping to a degree'', they were not be nearly enough to offset the large price falls, ASB rural economist Nathan Penny said.
ASB still expected prices to stabilise as global production moderated and Chinese demand kicked back into gear, but the starting point for the recovery was significantly lower than expected.
It was also much further into the season, with about a third of auction volumes now sold.
The bank's long-term positive view for dairy prices still held and it had pencilled in a $6.50 milk forecast for the 2015-16 season, Mr Penny said.
Sweet whey powder was sold for the first time this week on the GDT platform, offered by European dairy co-operative Molkerei Ammerland.
Chief executive Ralf Hinrichs said the company was pleased with the results, while GDT director Paul Grave said the online auction had now set a credible market-based benchmark price for globally traded SWP at $US1295 ($NZ1583) a tonne.
