Farmers in Canterbury and Wairarapa say their regions are already in the grip of a drought and want the government to make an official declaration now.
Primary Industries Minister Nathan Guy yesterday told farmers in mid-Canterbury that conditions did not yet exist to allow him to declare a state of drought and trigger extra funding and support for farmers.
The National Institute of Water and Atmospheric Research said soil in parts of the South Island was severely to extremely dry compared to an average January.
Jeremy Talbot grows feed for stock in South Canterbury, an area where there has been no significant rainfall since spring.
He said they had been in drought since December and this needs to be made official so an urgent stocktake can be done on how much feed is available around the country, to help farmers whose own paddocks are bare.
"So until the likes of a drought event is declared and someone is actually employed under the provisions of the Declaration of Drought to actually do that, nothing is going to happen.
"And in the meantime, we've got people fiddling while, virtually, Canterbury burns."
Mr Talbot said the lack rain means hay production was less than half what it would normally be at this time of the year.
He said feed shortages in the North Island mean dairy farmers in his region will have nowhere to turn to once the feed they are currently using runs out.
"What's going to happen later on? I mean, it's all very well, you've got the cows milking now and you might be able to buy a little bit of feed, but come the winter because the straw's not there ... I really am quite concerned that the situation is being grossly underestimated."
Mr Talbot was critical of Mr Guy for meeting with farmers in Mid-Canterbury instead of South Canterbury where the problem was worse.
The man who hosted Mr Guy at his house for the meeting, mid-Canterbury sheep and beef farmer Chris Allen, said nobody had been spared the effects of the dry weather.
"The dry-land farmer is struggling because they haven't had the growth that they would have normally had. Those that have taken on dairy heifers, dairy grazers, over a period of time - they are the ones that have to make the really expensive decisions to buy feed and to maintain that stock."
The only thing keeping some South Canterbury farms going is irrigation from the Opuha Dam - but even this is starting to run out.
The project's chief executive, Tony McCormack, said if there was no meaningful rain in the next month, the dam may have to shut off water to farmers completely for the first time in its 17-year history.
"Over the next few weeks as we approach that trigger level we'll be working with our farmers to see what the next step we can take is that will be effective at just trying to prolong the storage because what we're trying to do is avoid that cliff when suddenly we have to go from something to nothing."
Some farmers are calling for a scheme to take water from Lake Tekapo, but Canterbury Regional Council deputy chair David Caygill told Morning Report its study last year found while this was feasible, it was not economically viable.
Mr Caygill said many of the areas which are currently very dry will be helped by other projects, including the central plains canal scheme.
The dry weather has also hit dairy farmers in Wairarapa where normally milk production would be in full swing.
Dairy farmer, Chris Engel, said instead some are drying off cows early and preserving feed and that a drought needs to be declared now.
He said the low milk price coupled with a doubling in the price of feed due to high demand, is particularly tough on sharemilkers.
Mr Guy said his ministry has yet to receive a formal request asking for a drought to be declared.
"We're just gathering intelligence at the moment on a week-by-week basis. And there is a hell of a lot of support out there for farmers, particularly through the rural support trust, through Federated Farmers, through MPI."
NIWA weather forecaster Chris Brandolino said the dry conditions were working up the south and north islands, but there might be some short term respite for farmers today.
"Showers, maybe some thundery showers, east of the divide for both islands, for the south and the north island ... maybe 5 to 15 millimetres of rain in some areas over the next 12 to 18 hours."
Mr Brandolino said the rain needed to be sustained to improve soil moisture levels.
Farmers say it would take a sustained amount of rain to turn things around.