Northland farmers are at the mercy of the weather gods as more than two months without rain takes its toll.

MetService says it will be weeks before any significant rain falls in key farming areas, putting the country's two leading exports, meat and dairy, under enormous pressure with production beginning to crash.

Farmers are rapidly getting rid of stock because of the big dry, putting important exports "under the gun", Federated Farmers says.

And with no substantial rain forecast in the immediate future it's likely to get worse before it gets better.

Rainfall since October has been well below average for the west coast, and especially dry in January and February.  

Soil moisture deficit at Dargaville is nearing the permanent wilting point (150mm).

MetService Forecaster John Law said another high is due to settle in this week.

"It will most likely be at least mid-March before we see any significant rain, or it could be a bit longer," he said.

Latest Statistics NZ figures show a much worse than expected trade deficit of $305 million in January, when export returns fell sharply, especially for dairy products and crude oil.

A surplus of about $125m was expected.

Primary Industries Minister Nathan Guy visited Kylie and Malcolm Welsh's Baylys Coast Rd farm near Dargaville last week to declare Northland a medium scale adverse drought event - the last step before a national event.

"This is recognition that we are now beyond what is a normal dry summer and into an extreme climatic event," he said.

The declaration means extra government funding is now available to support organisations such as rural support trusts. 

There will also be rural assistance payments available in extreme situations.

Welsh milks 330 cows on his 200 hectare farm.

Other farmers have started milking once a day in response to the situation, but Welsh has maintained the practice he began in the 2010 drought - partially due to lifestyle choice, he said.

Looking at his withered farmland, it's easy to see why he needs to supplement 90 per cent of his herd's diet, averaging 9-10kg a day per cow.

"We will be $100,000 down on what we were budgeting - a combination of lost production and extra costs," he says. 

And with palm kernel prices going up 25 per cent in the past three weeks, those costs will reverberate.

But he admits he's one of the luckier ones. He has feed in reserve for the winter, and is better prepared than he was for the last drought.

"That came earlier in the year, so we were more in the peak production of milk than now. We've made a lot more production this time."

Other farmers might not fare so well.

Northland Federated Farmers president Matt Long said there was limited availability of palm kernel and none on the spot market unless a farmer has already contracted for it.

"You can't ring up and get it at any price," he said.

Julie Jouker, co-ordinator for Rural Support Trust, said many dairy farmers were still recovering from the 2010 drought.

"It's a lot tougher for them this time so we wanted to move quickly and let farmers know we're out there to support them."

Industry body DairyNZ is sending out weekly newsletters with practical advice and is also using discussion groups to help farmers find out how others are dealing with the dry conditions.

"The best support can be talking to your neighbours and just hearing what others are doing. That's what we're trying to facilitate through our farmer networks," regional team manager Craig McBeth said.

Northland MP Mike Sabin and Whangarei MP Phil Heatley have been giving Guy an "on-the-ground view" of the situation.

"I know farmers have been taking practical steps to deal with the drought, such as destocking and switching to once-a-day milking.

"Planning ahead in this manner is important, but so too is asking for help when needed, and I am glad of the support offered," Sabin said.