Dairy farmers suffering low prices could be hit twice over if drought conditions bring a cut in production this summer.
The risk of drought stems from the return of El Nino to the Pacific.
An El Nino stems from warmer than usual water in the central Pacific and can cool temperatures in winter and reduce rainfall in eastern areas in summer.
The last happened on a large scale in New Zealand in 1997 and 1998.
Official figures show this had a big effect, cutting agricultural production by $425 million over two years, and costing $1 billion in direct and indirect costs.
Any repeat of this would come at a bad time for farmers, with dairy prices still low despite a limited respite this week.