Farmers are being warned to prepare for a dry summer in case the current mild El Nino conditions intensify.
With summer starting unofficially today, Federated Farmers spokeswoman Katie Milne said some parts of the country were already experiencing drier weather than last year, which was causing concern.
"It is important that farmers have contingency plans in place, such as de-stocking and getting in supplementary feeds. If farmers have good plans ready, they can be proactive rather than reactive if a severe drought does eventuate."
Although there is no indication yet of that, Niwa is predicting below normal rainfall on the drought-prone North Island east coast and the northern South Island.
"It is times like these we see the real value in building more and better water storage schemes, particularly in areas prone to drought. Good water storage would help buffer farmers from the vagaries of the weather."
Northland experienced a severe drought in 2010 and much of New Zealand suffered dry conditions in 2008, with the Waikato recording its driest January in a century.